Tektronix 5958 Instruction Manual

Contains Operating Informat~ion

W ARRANTY

Keithley Instruments, Inc. warrants this product to be free from defects in material and workmanship for a period of 1 year from
date of shipment.

Keithley Instruments, Inc. warrants the following items for 90 days from the date of shipment: probes, cables, rechargeable batter­ies, diskettes, and documentation.

During the warranty period, we will, at our option, either repair or replace any product that proves to be defective.

To exercise this warranty, write or call your local Keithle y representative, or contact Keithle y headquarters in Cleveland, Ohio. Y ou
will be given prompt assistance and return instructions. Send the product, transportation prepaid, to the indicated service facility.
Repairs will be made and the product returned, transportation prepaid. Repaired or replaced products are warranted for the balance
of the original warranty period, or at least 90 days.

LIMIT A TION OF W ARRANTY

This warranty does not apply to defects resulting from product modification without Keithley’s express written consent, or misuse
of any product or part. This warranty also does not apply to fuses, software, non-rechargeable batteries, damage from battery leak­age, or problems arising from normal wear or failure to follow instructions.

THIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED OR IMPLIED, INCLUDING ANY IMPLIED
WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. THE REMEDIES PROVIDED HEREIN
ARE BUYER’S SOLE AND EXCLUSIVE REMEDIES.

NEITHER KEITHLEY INSTRUMENTS, INC. NOR ANY OF ITS EMPLOYEES SHALL BE LIABLE FOR ANY DIRECT,
INDIRECT, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OF ITS INSTRU­MENTS AND SOFTWARE EVEN IF KEITHLEY INSTRUMENTS, INC., HAS BEEN ADVISED IN ADVANCE OF THE POS­SIBILITY OF SUCH DAMAGES. SUCH EXCLUDED DAMAGES SHALL INCLUDE, BUT ARE NOT LIMITED TO: COSTS
OF REMOVAL AND INSTALLATION, LOSSES SUSTAINED AS THE RESULT OF INJURY TO ANY PERSON, OR DAM­AGE TO PR OPERTY.

Keithley Instruments, Inc. • 28775 Aurora Road • Cleveland, OH 44139 • 440-248-0400 • Fax: [phone] • http://www.keithle y.com

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1/99

Instruction Manual

Model 5958

C-V Software UtiliJies

01991, Keithley Instruments, Inc.

All Rights Reserved

Instruments Division

Cleveland, Ohio, U. S. A.

Document Number: 5958-901-01 Rev. A

All Keithley product names are trademarks or registered trademarki of Keithley Instruments. Inc.
Other brand and product names are trademarks or registered trademarks of their respective holders

MODEL 5958 C-V UTILITIES SOFTWARE

OVERVIEW
1NSTn”MENTS CONTROI.LED:

Required: Mode, 590 c-v Analyzer.
Optional: Model 7.30-l Voltage Source, Temptronic Hot Chuck (user

supplied, for BTS only), GLIB switch or prober. Switch Control Files are
provided for Keithley switching systems.

TESTS: Cunhols in~tmment~ to connect devices, acquire data, and stres

the device under test.

Bi.8 Temperahue stress WTS, cycle: Cycles the hot chuck specified by

the hot chuck COntml file.
programmable.

BTS Test Sequence: Tests up to 99 devices using specified C-V Peram-

eter, stress Cycle, Switch Controi, and Data Destination files.

Sequence Type: Sequen*ial, Parallel, or No Stress.
shxss Type: c the” -, - the” t, + only or - only.

Zerbst Test sequence: Tee, up to 99 devices using specified C-V

Farameter, c-t Parameter, SwitchControl, and Data Destination files.

sequence Type: Multiple C-V, One C-V, or No C-V.

DATADISPLAY:Graphicorlistdisp,ayofda~=aarrays.Tabular dispiay of

calculated parameters.

FILES:

C-V Parameter File LCVP): Contains all setup parameters for C-V

Measurements.

C-t Parameter File KTPF): Contains ail setup parameters for C-t Mea-

surements.

stress Cycle mra”le*er File LSCP): Contains a,, setup parameters for

Bias Temperature Stress cycles.

BTS Test Sequence File LBTS): Contains all setup parameters for BTS

Test Sequences.

Zerbst Test sequence File ,.ZTS): Contains all setup parameters for

Zerbst Test sequences.

Data Destination Files MJAT, .CTD): Each contains C-V or C-t curve

data, user-input device parameters, and derived results. Model 5958
C-V data files (.DATl are compatible with Model 5957v2.0.

Configuration File KFG): Specifies default paths and system configu-

ram* parameters.

Switch Coniml File LSWC): User-defined ASCII file containing the

necessary commands to make device connections with a GPIB device.
Commands include INIT. PARALLEL. DEVICE n, and FINAL.

Hot Chuck Contxool File LHCCb User-defined ASCII file containing the

necessary commands to controi a GPIB hot chuck.
include SENDWINDOW, SENDSETFOINT, SENDSRQMASK,
GETTEMF, NUMCHUCKS, CHUCKADDR. TERMINATOR,
SPATIEMF. and SFNOTBUSY.

CableCalibrationFi,e,.CAL): Contains referencecapacitorvaiuesand

culibratiionconstantsto bessntto theModel tocalibrateparticular
range and frequency combinations.

Material Constants File MATERIALCON): Specifies material con-

stants to be used in anaiysis such as insuiator and semiconductor
permittivity, bandgap energy, intrinsic carrier concentration, metal
work function, and electron affinity.

CAPACITANCE MEASUREMENT CAPABILITY:

Test Signal Frequency: 100kHz or IMHz.
100kH2MeasurementRanges: ZpF/2uS,20pF/20uS,?00pF/?BBuS,and

Z”F,2”lS.

SLXSS temperalure t&e and voltage are

Commands

Bias Voltage Wavefom: Stair and pulsed star waveforms.
Measurement Rates ,readings/sec): 1,10,18, and 75. 1000 rcading,scc.

available also for C-t measurement.
Seiectable measurement filter and series or parallel device model.
C-t Sample Time: lmsec to 65 set per sample, up to 450 samples (up to

1350 samples at the 1000,sec measurement rate).

ANALYSIS

MIS Analysis Constants: Oxide capacitance and thickness, gate area.

seriesresistance, equilibriumminimumcapacitance, averagedoping,

bulk doping, device type. Debye length, flatband capacitance and

voltage, work function difference. threshoid voltage, effective oxide

charge and charge concentration. best depth, and capaatance gain

and offset.
Doping Profile: Depiction approximation doping versus depletmn

depthanddepth”ersusgate”oltagc,ZieglermethodMajorityC~rrier

Corrected WCC, doping profile.
Bias Temperature Stress: Mobile ionic charge, total fined oxide charge

K&d, oxide capacitance and thickness, gate area. series resistance.

equilibrium minimum capacitance, average doping, bulk doping,

device type. “atband capacitanceand voltage, threshold voltage, and

capacitance gain and offset.
C-“Zerbst: Zerbst plot of C-t data to determine carrier generation

lifetime, surface generation velocity.

SYSTEM REQUIREMENTS
RECOMMENDED COMP”TER CONFIGURATION: IBM compatible

80386with80287ar80387mathcapracessorilnddiskcache,blOkBRAM,
hard disk drive. 1.2MB S&inch or 720kB SM-inch floppy drive, EGA or
VGA monitor, Microsoft or Logitech mouse.

MINIMUM COMPUTER CONFIGURATION: IBM AT, I’S,*, or I”O%

compatible, 640kB RAM, hard disk drive. 1.2M8 SlYa-inch or 720kB
3% inch floppy drive.

OPERATING SYSTEM: MS-DOS or PC-DOS 3.2 hninimum~.
GRAPHlCS ADAPTER: CGA, EGA, “GH CEGh “mdd, or Nercuies

Graphics Adapter.

MEMORY and DISK STORAGE REQUIREMENTS: 4.5MB of hard disk

space (prior to instailationl and 400kB free conventional RAM.

IEEE-488 (GPIB) INTERFACE CARDS SUPPORTED:

Using IOtech Driver 488 software V2.64 o* earlier:

CapitalEquipmentPC~88,4x488: IBMGPIBAdapter; IOtechCP488,

GP488A. GP48BB+, MP.488. MP488CT; Keithley FC488-CEC, G&88-

CEC-OM, 41188.CEC-IM; Mehabyre KM488-DD, KM488-ROM;

National I”shume”ts PC-II, PC-m., PC-III.

Using IO&h Driver 488 software X2.61:

I&!ch 6P488B+, lMP488, Mr48BCT.

lotech Personal 488/2 is require* for Psi2 operation.

COMPATIBLEPRINTERS: CmnonBJ80; CItohProwriter: C. Itoh24LQ;

Epson Fx, RX, MX. LQISOO; HP Think k-t. Laser let+; IBM Graphic or
Professional: NEC 8023,8025: NEC Pinwriter F Series: Okidata 92.93,

192~; Smith Corona D100; Tektronix 469516: Toshiba 24 pin.

CDMPATIBLE PLOTTERS: Epson HI-80: Hewlett-Pa&r& 747O.:G’5,

7440; Houston DMP-XX; Roland DXY-800; Watanabe Digi-Plot.

COMPATIBLE MOUSE: Mi~nxoft or Logitcch mouse with MOUSESYS

installed.

MATERIALS PROVIDED:

Inshlxtion ma”“al.
Diskettes containing instailation, programs, source code. and sample

data.

‘Note: ~Microsoft BASIC 7.1 required to modify source code.
Specifications subject to change without notice.

Table of Contents

SECTION 1

1.1

1.2

1.3

1.4

1.5

1.6

1.7

1.7.1

1.7.2

1.7.3

1.7.4

1.7.5

1.8

1.9

1.9.1.

1.9.2

1.9.3

1.9.4

1.9.5 Hot Chuck and Probe Station ..................

1.9.6

- General Information

INTRODUCTION

FEATURES ..................................

WARRANTY INFORMATION
MANLJAL ADDENDA

SAFETY SYMBOLS AND TERMS .................

SPECIFICATIONS ............................

COMPUTER REQUIREMENTS

Computer Hardware Requirements ..............

Supported Graphics Cards ....................

Supported IEEE-488 Interfaces .................

Recommended Printers and Plotters .............

Software Requirements

REQUIRED EQUIPMENT .......................

OPTIONAL ACCESSORIES

Voltage Source

Connecting Cables

Calibration Sources

Rack Mount Kits

Switching Equipment

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1-l
l-1
l-1
l-1
l-1

1.?
I-2
1-2
1-3
1-3
I-3
l-4
l-4
l-5
l-5
1-5
1-5
l-5
1-5

I-6

SECTION 2

2.1

2.2

2.2.1

2.2.2

2.2.3

2.3

2.3.1

2.3.2

2.3.3

2.3.4

2.3.5

2.3.6

2.4

2.4.1

2.4.2

2.4.3

2.4.4 LightConnections

2.5

2.5.1

- Getting Started

INTRODUCTION ...........................................

IEEE-488 BUS CONSIDERATIONS

Interface Card Installation
BusConnections..

Default Primary Address Settings .............................

SOWARE INSTALLATION .................................

SoftwareBackup

Installation Procedure ......................................

IEEE-488 Driver Software Installation

CONFIGSYSModification ..................................

Plotter and Printer Considerations .............................

Memory and Hard Disk Considerations ........................

TEST CONNECTIONS .......................................

C-V Analyzer Connections ..................................

Optional Voltage Source Connections ..........................

Typical Switching Card Connections

CABLECORRECTION

When to Perform Cable Correction

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2-l
2-I
2-1
2-2
2-2
2-3
2-3
2-3
2-5
2-5
2-5
2-6
2-6
2-6
2-7

2-7
z-10
2-12
2-12

2.5.2

2.5.3

2.5.4

2.5.5

2.5.6

2.6

2.6.1

2.6.2

2.6.3

2.6.4

2.6.5

2.6.6

2.6.7

2.6.8

2.6.9

2.7

2.7.1

2.7.2

2.7.3

2.7.4

Recommended Correction Sources
Calibration Source Connections
Correction Procedure
Optimizing Correction Accuracy to Probe Tips
Cable Correcting Switching Pathways

RUNNING THE SOFTWARE

Starting the Program

Default Paths
Run Tie Considerations
Selecting Menu Items
Main Menu Description

FileTypes ......................................

Running with Floppy-Based Test/Data Files

Printing Screens
Default Material Constants

TEST SETUP, MEASUREMENT AND ANALYSIS OVERVIEW

C-V Measurement Overview

C-t Measurement Overview

BTS Measurement Overview
Zerbst Measurement Overview

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2-12
2-12
2-13
2-13
Z-13
2-14
2-14
z-14

2-14
2-14
2-15
2-15
2-16

2-16
2-16
Z-16
2-16
2-17
2-18
2-19

SECTION 3

3.1

3.2

3.2.1

3.2.2

3.2.3

3.2.4

3.2.5

3.2.6

3.2.7

3.3

3.3.1

3.3.2

3.3.3

3.3.4

3.3.5

3.3.6

3.3.7

3.4

3.4.1

3.4.2

3.4.3

3.4.4

3.4.5

3.5

3.5.1

INTRODUCTION ........................

C-V MEASUREMENT PARAMETERS

C-V Measurement Parameter Menu

C-V Measurement Parameters .............

Waveform Parameters ...................

Bias Voltage Parameters .................

Miscellaneous Parameters ................

C-V Parameter Programming Procedure
Saving/Loading C-V Measurement Parameters

C-t MEASUREMENT PARAMETERS

C-t Measurement Parameter Menu

C-t Measurement Parameters .............

Waveform Time Parameters ..............

Bias Voltage Parameters .................

Cabie Correction Filename ...............

C-t Parameter Programming Procedure

Saving/Loading C-t Measurement Parameters

STRESS CYCLE PARAMETERS .............

Stress Cycle Parameter Menu .............

stress Cycle Parameters .................

Programming Stress Cycle Parameters

Saving/Loading Stress Cycle Parameters

Stress Cycle Description .................

BTS TEST SEQUENCE ....................

BTS Test Sequence Menu ................

- Test Setup

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3-1
3-1
3-I
3-2
3-3
3-4

3-I
3-4
3-5
3-5
3-5
3-6
3-6
3-6
3-6
3-8

3-8
3-8
3-8
3-8
3-9
3-9
3-10
3-11
3-11

3.5.2

3.53

3.5.4

3.5.5

3.6

3.6.1

3.6.2

3.6.3

3.6.4

3.6.5

BTS Test Sequence Setup Parameters

Setting Up a BTS Test Sequence

Saving/Loading BTS Test Sequence Setups
BTS Test Sequence Description

ZERBST TEST SEQUENCE

Zerbst Test Sequence Setup Menu
Zerbst Test Sequence Setup Parameters
Setting Up a Zerbst Test Sequence
Saving/Loading Zerbst Test Sequence Sehlps
Zerbst Test Sequence Types

SECTION 4 - Measurement

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3-11
3-12
3-12
3-12
3-19
3-19
3-19

3-20
3-20
3-21

4.1

4.2

4.2.1

4.2.2

4.2.3

4.2.4 DeterminingCMIN

4.3 C-t MEASUREMENTS

4.3.1 C-t Measurement Connections

4.3.2 Choosing Optimum C-t Measurement Parameters

4.3.3 C-t Measurement Procedure

4.4

4.4.1 Hot Chuck Connections

4.4.2 Selecting Optimum Voltage, Temperature, and Time Parameters

4.4.3 Performing a BTS Stress Cycle

4.5 BTS TEST SEQUENCE MEASUREMENTS

4.5.1 BTS Test Sequence Connections

4.5.2 Cable Correcting Switching Pathways

4.5.3

4.5.4 Parallel BTS Test Measurement Overload

4.5.5

4.6 ZERBST TEST SEQUENCE MEASUREMENTS

4.6.1 Zerbst Test Sequence Connections

4.6.2

4.6.3 Running a Zerbst Test Sequence

4.7

4.7.1

4.7.2 Avoiding Capacitance Errors

4.7.3 Correcting Residual Errors

4.7.4 Interpreting c-v Curves

4.7.5 Dynamic Range Considerations

4.7.6

4.7.7 Device Considerations

4.7.8 Test Equipment Considerations

INTRODUCTION

C-V MEASUREMENTS

C-V Measurement Connections
Selecting Optimum C-V Measurement Parameters
C-V Measurement Procedure

BTSSTRESSCYCLE..

Selecting Optimum BTS Test Sequence Parameters

BTS Test Sequence Procedure

Selecting Optimum Zerbst Sequence Parameters

MEASUREMENT CONSIDERATIONS

Potential Error Sources

Series and Parallel Model Eq.livalent Circuits

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4-1
4-l
4-l
4-2
4-3
4-6
4-10
4-10
4-10
4-11
4-14
4-14
4-14
4-14

4.17
4-17
4-21
4-22
4-22

4-22
4-23
4-23
4-25

4-25

4-26
4-26

4-29
4-29
4-30

4-32

4-32

4-33

4-34

SECTION 5 - Analysis

5.1

5.2

5.2.1

5.2.2

5.3

5.3.1

5.3.2

5.3.3

5.3.4

5.4

5.4.1

5.4.2

5.4.3

5.4.4

5.5

5.5.1

5.5.2

5.5.3

5.5.4

5.5.5

5.5.6

5.6

5.6.1

5.6.2

5.6.3

5.6.4

5.6.5

5.6.6

5.6.7

5.6.8

5.6.9

5.6.10

5.6.11

56.12

5.6.13

5.6.14

5.6.15

5.6.16

5.6.17

5.7

5.7.1

5.7.2

57.3

57.4

5.7.5

5.7.6

INTRODUCTION
DEFAULT CONSTANTS AND SYMBOLS USED FOR ANALYSIS

DefaultConstants..
Calculated Data Symbols

OBTAINING BASIC ANALYSIS INFORMATION FORM HIGH-FREQUENCY C-V CURVES

Basic High-frequency C-V Curves
Determining Device Type
Oxide Capacitance and Minimum Capacitance

Flatband Voltage and Threshold Voltage

LOADING AND SAVING DATA

Filename Formats for Data Files

LoadingData
SavingData
Importing Data into Other Programs

GRAPHICALANALYSIS..

GraphicsControlMenu
Controlling Hard Copy Size and Resolution
cursoroperation
Threshold Voltage and Flatband Voltage Display
OverlayingCLuves
Selecting the Graphics Range

C-VANALYSIS

C-VAnalysisMenu

Loading and Saving C-V Data Files

Displaying Analysis Constants
Oxide Capacitance, Thickness, and Area Calculations
Series Resistance Calculations

Flatband Capacitance and Flatband Voltage
ThresholdVoltage
Metal Semiconductor Work Function Difference

EffectiveOxideCharge.
Effective Oxide Charge Concentration
Average Doping Concentration

B&Depth
Gain and Offset

Displaying C-V Data Arrays

Printing Analysis Constants and C-V Data Arrays
Graphing C-V Data
Ziegler (MC0 Doping Profile

C-t ANALYSIS

C-t Analysis Menu
Zerbst Analysis Data
Loading and Saving C-t and Zerbst Data

Displaying Analysis Constants

Displaying C-t Data Arrays

Printing Analysis Constants and C-t Data Arrays

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5-l
5-1
5-l

5-l
j-3
j-3
5-3
54
54
5-4
54
j-5
5-6
5-7
5-8
5-8
5-9
5-9
5-10
5-10
5-10
j-10
j-10
S-11
j-11
j-17
j-17
S-17
5-18
5-18
5-19
5-19
5-19

5.20
5-20
5-20
5-20
5-22

5-24
5-26
5-26

5.27

5-27

5-27
5-27
5-27

5.7.7

5.8

58.1

5.8.2

5.8.3

5.8.4

5.8.5

5.8.6

5.8.7

5.8.8

5.9

5.9.1

5.92

Graphing C-t Data

BTSANALYSIS ...........................

BTS Analysis Menu

Loading and Saving BTS Data
Displaying BTS Analysis Constants
Displaying BTS Data Arrays
Printing Analysis Constants and BTS Data Arrays
Flatband Voltage and Threshold Voltage
Mobile Ion Calculations
Graphing BTS Data

REFERENCES AND BIBLIOGRAPHY

References ......................

Bibliography .....................

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SECTION 6 - Bus Control File Setup

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5-28
j-31
j-31
5-32
5-32
j-32
j-34

j-34

j-34

5-37
5-39
5-39
j-39

6.1

6.2

6.2.1

6.2.2

6.2.3

6.2.4

6.3

6.3.1

6.3.2

6.3.3

6.3.4

6.4

6.4.1

6.4.2

6.4.3

INTRODUCTION ............................

SWITCH CONTROL

Switch Control File Description ................

Switch Control File Commands ................

Switch Control Examples ....................

Setting Up a Switch Control File

PROBE SEQUENCER CONTROL ................

Using Switch Control File Commands ...........

Programming constraints

Hypothetical Probe Sequencer Commands .......

Example Hypothetical Probe Sequencer Control File

HOT CHUCK CONTROL

Hot Chuck Control File Description .............

Hot Chuck Control File Commands .............

Setting Up a Hot Chuck Control File ............

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APPENDICES

A Material Constants File Modification
B Summary of Analysis Equations
C
D
E
F Graphic 4.0 Functions Used by Model 5956
G
H
I Error Messages

J

C-V Analysis Constants
Disk File Formats
Cable Calibration Utility

Software Modification
Using the Model 5958 with Other Programs

Default Switch Control Files

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6-1

6-1

6-l
6-l

6-7

6-7

6-11

6-11

6-11

6-11

6-12

6-12
6-12

6-12

6-23

A-l
B-l
C-l
D-l
E-l
F-l
G-l

H-l
I-1

J-1

List of Illustrations

SECTION 2 - Getting Started

Figure 2-I
Figure 2-2
Figure 2-3

Figure 2-4
Figure 2-5
Figure 2-6 Model 230-I Voltage Source Digital I/O Port Terminal Arrangement
Figure 2-7
Figure 2-8
Figure 2-9

IEEE-488 Bus Connections
Typical C-V Analyzer Connections
Optional Voltage Source Connections
RF Switch Card Example
Typical Matrix Card Connections

Direct LED Control

Relay Light Control

CalibrationSourceConnections

.....................................

...............................

.........................

.......................

................................

..........................

....................................

...........................

SECTION 3 - Test Setup

Figure 3-I
Figure 3-2
Figure 3-3
Figure 3-4
Figure 3-5
Figure 3-6
Figure 3-7
Figure 3-8
Figure 3-9 BTS Sequential Test Flowchart (+ Then Stress Cycle)
Figure 3-10
Figure 3-11
Figure 3-12

Figure 3-13 BTS Parallel Test Sequence Flowchart (+Then -Stress Cycle)
Figure 3-14 BTS Parallel Test Sequence Flowchart (-Then +Stress Cycle)
Figure 3-15 BTS Parallel Test Sequence Flowchart (+Only Stress Cycle)
Figure 3-16

Figure 3-17 BTS No Stress Sequence Flowchart
Figure 3-18 Zerbst Test Sequence Menu
Figure 3-19
Figure 3-20

Figure 3-21 No C-V Test Sequence Flowchart

C-V Measurement Parameters Menu
Stairwaveform
Pulse stair Waveform
C-t Measurement Parameters Menu
C-twaveform
BTS Cycle Parameters Menu
Stress Cycle Flowchart
BTS Test Sequence Setup Menu

BTS Sequential Test Flowchart (-Then +Stress Cycle)
BTS Sequential Test Flowchart (+ Only Stress Cycle)
BTS Sequential Test Flowchart (-Only Stress Cycle)

BTS Parallel Test Sequence Flowchart C-only Stress Cycle)

Multiple C-V Sequence Flowchart
One C-V Test Sequence Flowchart

.........................................

.....................................

...........................................

................................

....................................

.................................

..........................

..........................

..............................

.............

.............

..............

..............

........

........

.........

.........

...........................

............................

............................

............................

2-2
2-7
2-8

2-8
2-9
z-10
2-10
2-11
2-13

3-2
3-3
3‘l
3-5
3-7
3-9
3-10

3-11
3-13
3-14
3-14

3-15

3-16

3-17

3-17
3-18

3-18

3-20

3-22

3-22

3-23

SECTION 4 - Measurement

Figure 4-l
Figure4-2 Basic High-frequency C-V Curve
Figure 4-3
Figure 4-4
Figure 4-5 C-V Sweep Cycle Completed Window

Typical Test Connections for Basic C-V and C-t Measurements

..................................

RunC-VSweepWindow

C-V Sweep in Progress Window

........................................

...................................

..............................

............

4-2

4-3

4-4

4-5

4-s

Figure 4-6
Figure 4-7
Figure 4-8

Figure 4-9 VoltageAppliedWindow
Figure 4-10

Figure 4-l 1

Figure 4-12
Figure 4-13
Figure 4-14
Figure 4-15
Figure 4-16
Figure 4-17
Figure 4-18 Typical Model 7062 RF Switch Card Connections
Figure 4-19
Figure 4-20
Figure 4-21 Typical Switch Card Cable Correction Connections
Figure 4-22
Figure 4-23
Figure 4-24 Run Zerbst Test Sequence Window
Figure 4-25 Zerbst Test Sequence in Progress Window
Figure 4-26
Figure 4-27 High Frequency Curve with Added Noise
Figure 4-28 High Frequency Curve Resulting from Gain Error
Figure 4-29 Zerbst Plot Affected by Shay Capacitance
Figure 4-30 High Frequency Curve Caused by Nonlinearity
Figure 4-31
Figure 4-32
Figure 4-33 Curve Distortion when Hold Time is too Short
Figure 4-34 Series and Parallel Impedances

Auto/Manual Selection Window
Inversion Voltage Window
New Inversion Voltage Window

...................................................

CMINDisplayWindow ......................................................

Auto Cm Measurement Method

RunC-tSweepWindow
C-t Sweep in Progress Window
C-t Sweep Completed Window

BTSCycleWindow ........................................................

BTS Cycle in Progress Window

BTS Cycle Completed Window

Typical Model 70748/7075 Test Connections
Typical’Model7073 Coaxial Matrix Card Connections

Run BTS Test Sequence Window

BTS Test Sequence in Progress Window

High Frequency C-V Curve with Capacitance Offset

Normal High C-V Curve Results When Device is Kept in Equilibrium

Curve Hysteresis Resulting When Sweep is too Rapid

....................................................

.............................................

..................................................

..............................................

.............................................

...............................................

...............................................

...............................................

............................................... 4-16

....................................

.............................................. 4-24

........................................

............................................

......................................

....................................... 4-28

....................................... 4-28

............................................... 4-32

.................................

..............................

................................

...............................

.................................

..................................

..............................

...................................

..................

4-7
4-7
4-8
4-8
4-9
4-9

4-12
4-13
4-13
4-15
4-16

4-18
4-18
4-19
4-22

4-24
4-26
4-27

4-28

4-28

4-28

4-30
4-31
4-31

SECTION 5 - Analysis

Figure 5-l
Figure 5-2
Figure 5-3
Figure 5-4
Figure 5-5
Figure 5-6
Figure 5-7
Figure 5-8
Figure 5-9
Figure 5-10
Figure 5-11
Figure 5-12

Figure 5-13
Figure 5-14
Figure 5-15
Figure 5-16

High-frequency C-V Characteristics of p-lype Material

High-frequency C-V Characteristics of n-type Material

Load File Window ............................

Save File Window .............................

Graphics Control Menu ........................

Select Graphics Range Window
C-V Analysis Constants Window

Enter l&e Window ..........................

Enter Cox Window ............................

Enter Area Window ...........................

Enter tax Window .............................

Enter CMw Window ...........................

Enter Nww Window ...........................

Simplified Model used to Determine Series Resistance

Measurement Array Display Example

Calculated Data Array Display Example

...................

.................

..............

............

53
j-4
5-6
5-7
5-Y
5-10
5-12
s-14
5-14
S-15
5-15
5-16
5-16
j-17
5-21
5-21

Figure 5-17 C vs. Vds Example
Figure 5-18 G vs. Vts Example
Figure 5-19 Depth vs. Gate Voltage Example
Figure 5-20

Figure 5-21 Ziegler (MCC) Doping Profile Example
Figure 5-22
Figure 5-23 Cvs.tExamplePlot

Figure 5-24 Zerbst Example Plot
Figure 5-25 Zerbst Plot with Generation Lifetime and Generation Velocity Displayed

Figure 5-26 BTS Analysis Constants Window

Figure 5-27 BTS Analysis Capacitance Array Display Example

Figure 5-28 BTSCvs.V‘sPlot

Figure 5-29 BTSRvs.VcsPlot

Doping Profile vs. Depth Example

C-t Measurement Array Display Example

...................................................

...................................................

........................................

......................................

...................................

.................................

.................................................

.................................................

.......................................

...........................

...................................................

...................................................

SECTION 6 - Bus Control File Setup

.........

j-22

j-23
5-24
5-25
5-25
5-28
j-29
i-30
5-31
5-33
5-33
5-38
5-38

Figure 6-l
Figure 6-2
Figure 6-3
Figure 6-4

Model 7062 Switching Configuration

Model 7074D/7075 Switching Configuration

Model 7073 Switching Configuration

Default Contents of Tl’0315B.HCC File

.........................................

.........................................

.......................................

...................................

6-8
6-9

6..lO
6-23

List of Tables

SECTION 1

Table 1-l
Table l-2
Table l-3
Table 14

Table l-5
Table l-6
Table l-7
Table l-8

SECTION 2

Table 2-l
Table 2-2
Table 2-3
Table 24
Table 2-5 Cable Correction Sources
Table 2-6

- General Information

Computer Hardware Requirements
Graphics Cards Supported by Model 5958

IEEE-488 Interfaces Supported by Model 5958
Recommended Printers
Recommended Plotters
Software Requirements
Required Equipment
Switch Selection Table for Model 5958 Tests

- Getting Started

Default Directories
Supported Graphics Cards
Supported l’rinters and Plotters

Model 230-l Digital I/O Port Terminal Assignments

F&Types ................................

.........................

SECTION 3 - Test Setup

Table 3-l

ReadingRates.......................................................

...................

...............

....................

............

..........

............

............

............

............

............

................

................

................

................

................

................

l-2

1-3

1-3
1-3
l-3

1-4

I-4

1-7

2-4

24

2-5

Z-10

2-12

2-15

3-2

SECTION 4 - Measurement

Table 4-l Switch Control File for Model 7062 RF Card Example
Table 4-2 Switch Control File for Model 7074D/7075 Card Example
Table 4-3 Switch Control File for Model 7073 Card Example
Table 4-4 Converting Series-parallel Equivalent Circuits

.....................

...............

..................

SECTION 5 - Analysis

Table 5-l
Table 5-2
Table 5-3
Table 5-4 C-V Analysis Constants

Default Material Constants
Calculated Data Symbols
Filename Formats for Data Files

...................................

.................................... 5-2

...............................

.....................................

............

4-20
4-20
4-21

4-33

5-2

5-5
j-12

SECTION 6 - Bus Control File Setup

Table 6-1
Table 6-2
Table 6-3
Table 6-4
Table 6-S

Switch Control File Commands
Hypothetical Probe Sequencer Commands
Example Switch Controi File for Hypothetical Probe Sequencer
Default Hot Chuck Control File Commands
Hot Chuck Control File Command Summary

...............................................

..........................

..................................... 6-12

....................................

.......................

6-2

........... 6-I 1

6-12

6-13

SECTION 1

General Information

1 .l INTRODUCTION

This section contains overview information for the

Model 5958 C-V Software Utilities and is organized as
follows:

1.2 Features

1.3 Warranty Information

1.4 Manual Addenda

1.5 Safety Symbols and Terms

1.6

Specifications

1.7

Computer Requirements

1.8 Required Equipment

1.9 Optional Accessories

1.2 FEATURES

The Model 5958 C-V Utilities software package is de­signed to perform BTS (bias temperature stress) meas­urements and Zerbst analysis on semiconductors with
the aid of a user-supplied Model 590 C-V Analyzer. A
Temptronic Model Tl’0315B Hot Chuck (not supplied) is
required for BTS measurements.

. C-V and C-t measurements

l

Insulator thickness or gate area from high-frequency
c-v measurements.

l

Semiconductor average doping
. Insulator mobile ion charge density
. Effective surface charge

l

Minority carrier lifetime

l

Surface generation velocity

l

Flatband voltage and capacitance
. Threshold voltage
. Metal semiconductor work function

1.3 WARRANTY INFORMATION

Warranty information is located on the inside front cover
of this instruction manual. Should you require warranty
service, contact your Keithley representative or the fac­tory for further information.

1.4 MANUAL ADDENDA

Any improvements or changes concerning the Model
5958 will be explained on a separate addendum supplied
with the manual. Please be sure to note these changes and
incorporate them into the manual before using the soft­ware.

Model 5958 measurement and analysis capabilities in­clude:

1.5 SAFETY SYMBOLS AND TERMS

The following safety symbols and terms may be found on

one of the instruments or used in this manual:

SECTION 1
General

Information

The A
should consult the operating instructions in the associ­ated manual.

The WARNING heading used in this and other manuals
cautions against possible hazards that could lead to per­sonal injury or death.

A CAUTION heading outlines dangers that could lead to
instrument damage. Such damage may invalidate the

warranty.

symbol on an instrument indicates that you

1.6 SPECIFICATIONS

Detailed specifications for the Model 5958 are located at
the front of this instruction manual. Specifications for
equipment used with the Model 5958
respective instruction manuals.

can

be found in the

Table l-l. Computer Hardware Requirements

1.7 COMPUTER REQUIREMENTS

The following paragraphs discuss minimum computer
requirements, supported graphics and interface cards,
supported plotters and printers, and required system
software.

1.7.1 Computer Hardware Requirements

The Model 5958 software is intended to run on IBM AT,
IS/Z, or compatible computers. Table 1-l summarizes

the minimum required computer configuration.

NOTE
A coprocessor-equipped 386-based computer
is recommended for best performance. Also, a
smart extended memory manager such as
SMARTDRVSYS may speed up program op­eration if you have extended or expanded
memory.

Description Requirements

Computer IBM AT, I’S/2, or 100% compatibie”

Minimum RAM

Disk drives

Monitor/graphics card Color or monochrome (see Table l-2)

Inshument interface

*Compatible X36-based machines such as the Compaq 386 can also be used. NOTE: select IBM graphics mode;
Compaq graphics is not supported.

640KB
Harddrive,oneLZMB5 1/4”,or720KB3-l/2” floppydisk
drive

IEEE-488

(see Table l-3)

.._

I

l-7.

Grneral

SECTION 1

Information

1.7.2

Table 1-2 lists the graphics card supported by the Model

5958.

1 Grmhics Cards

IBM CGA or 100% compatible
IBM EGA or 100% compatible
IBM VGA or 100% compatible (EGA mode)
Hercules monochrome or 100% compatible
Tseng EVA
Tecmar Graphics Master
T&Video AT
T&Video HRCGB
Sigma Color 400
AT&T 6300
Corona PC
Corona PC400
Corona ATI’
H.l’ Vectra

T.I. Professional

Supported Graphics Cards

Table 1-2. Graphics Cards Supported by

Model 5958

1.7.4 Recommended Printers and
Plotters

A user-supplied printer or plotter is required for hard
copy graphs or data printouts. Table 1-4 summarizes rec­ommended printers, and Table l-5 lists plotters. Addi­tional plotter and printer considerations are discussed in
paragraph 2.3.

I

Table 1-4. Recommended Printers

I Printer

NEC 8023, C. Itoh Prowriter

Cannon BJ80

Epson FX, MX, RX
Okidata 92,93
Smith Corona DlOO

IBM Graphics
Tektronix 4695/6
C. Itoh 24LQ, Toshiba 24 pin
Epson LQl500

HP Laser Jet+ (or compatible)
Okidata 192+

HP Think Jet

NEC Pinwriter

1.7.3

Table l-3 lists computer IEEE-488 interfaces supported
by the Model 5958.

Table 1-3. IEEE-488 Interfaces Supported by

K-488,4-488
GPIB
GP488f 2’

* This interface is required for I’S/2 machines, the remainder are
used with AT and compatibles.

Supported IEEE-488 Interfaces

Model 5958

CapitoiEquipment Corp.
IBM
IOtech

Table 1-5. Recommended Plotters

Plotter

Hewlett-Packard 7440,7475,7440
Watanabe Digiplot
Houston DMP-XX
Roland DXY-800
Epson HI-80

NOTE: Plotters mut support HPGL graphics language.

1-3

SECTION 1
Grneral

Information

1.7.5

Table l-6 summarizes the required computer sofhuare.

Additional information on software installation is lo­cated in paragraph 2.3.

Software Requirements

Table 1-6. Software Requirements

Software
MS-DOS or PC-DOS, version 3.2 or higher

IO&h Driver488*
Microsoft BASIC, version 7.1*”

’ Driver488 is suppiied with the Model 5958.
‘* BASK is not supplied and is necessary only if you intend to modify the murce code.

Table 1-7. Required Equipment

1.8 REQUIRED EQUIPMENT

Table l-7 summarizes the minimum equipment required
to use the Model 5958 software. Additional optional
equipment may be added to enhance capabiiities; see
paragraph 1.9 for a summary of recommended optional
equipment.

Comments
Operating system

IEEE-488 interface driver
Compile/link source code

Description I comments

Keithley Model 590 C-V Analyzer

Temptronic Tl’O315B Thermochuck equipped
with SA4430 IEEE-488 interface’

Keithley Model 7007 IEEE-488 cables (2) Connects C-V analyzer and hot chuck to computer IEEE-488

Keithley Model 70515OQ BNC cables
(2 minimum, 3 minimum with Model 230-I
Voltage Source)

Model 5905,5906,5907 or 5909 Calibration
SOUCi?S”

* Program can be user modified for use with other hot chucks. See Section 6 far details on modifying hot chuck driver file.
“Calibration sources are recommended for ,zrforming the cable correction procedure, a requirement foro@imizing high-frequency C-V measure­ment accuracy. Use Model 5905 Sources to calibrate 20pF, ?OOpF, and 2nF ranges. “se Mode, 5906 Sources to calibrate a,, Mode, 590 ranges. “se
Model 5907 Sources to calibrate oniy the 2°F range. Use Mode, 5909 sources to calibrate only 20OpF md 2nF ranges.

Model 590/100k: 1OOkHz test frequency

Model 590/1M: IMHz test frequency
Model 590/100k/lM: IOOkHz and IMHz test frequencies

Required for BTS tests

interface

Connects C-V analyzer to prober, Model 230-l trigger output to
Model 590 trigger input.

Aid in performing cable correction (see paragraph 1.9.3)

l-4

General

SECTION 1

Information

1.9 OPTIONAL ACCESSORIES

The optional accessories described below can be used to

enhance Mode1 5958 capabilities and are available from
Keithley Instruments or third-party sources as noted.

1.9.1 Voltage Source

Mode1 230-l Programmable Voltage Source: Extends the
normal i2OV DC bias range of a Model 5958 system to
+lOOV and also adds light-control capability using the
digital I/O port. A Model 4851 BNC Shorting Plug and a
BNC cable are also required for this application.

1.92 Connecting Cables

Model 7007 Shielded IEEE-488 Cables: Shielded
IEEE488 cables with a shielded connector on e&h end
(metric). Available as Model 7007-l Urn, 3.3 ft. long), and
Model 7007-2 (Zm, 6.6 ft. long).

Model 7051 BNC to BNC Cables: 5OQ (RG-580 BNC to
BNC coaxial cables, available as Model 7051-2 (0.6m, 2ft.
long), Model 7051-5 (1.5m, 5 ft. long), and Model 7051-10
(3m, 10 ft. long).

1.9.3 Calibration Sources

Model 5905 Calibration Sources: Includes 4.7pF, 18pF,
47pF, 18OpF, 47OpF, and 1.8nF capacitance sources,
180@, 1.8mS, and 18mS conductance sources and two fe­male-to-female BNC barrels. These sources can be used
to cable calibrate the 2OpF. 200pF, and 2nF ranges, and
they can also be used for standard instrument calibration
of the 20pF through 2nF ranges.

female BNC barrels. These sources will cable calibrate
only the 2nF range.

Model 5909 Calibration Sources: Includes 47pF, 180pF,
470pF, and 1.8nF capacitance calibration sources and two
female-to-female BNC barrels. These sources will cable
calibrate the 200pF and 2nF ranges.

1.9.4 Rack Mount Kits

Model 1019A-1 Fixed Rack Mount Kit: Mounts the op­tional Mode1 230-l Voltage Source in a standard 19-inch
rack or equipment cabinet.

Model 1019A-2 Fixed Rack Mount Kit: Mounts the op­tional Model 230-l Voltage Source and a second similar
instrument side-by-side in a standard 19-inch rack or
equipment cabinet.

Model 2288 Fixed Rack Mount Kit: Mounts one Model
590C-VAnalyzerinastandard19inchrackorequipment
cabinet.

Model 8000-14 Equipment Cabinet: A standard 14.inch
high, 19-inch wide equipment cabinet, which can be used
to enclose instruments used with the Model 5958. Rack
mount kits (above) are also required.

1.95 Hot Chuck and Probe Station

Temptronic TPO315B Thermochuck accessories:

. 4,5,6, or 8” hot chuck

l

Extended temperature range option (300°C)

Model 5906 Calibration Sources: Includes 0.5pF, 1.5pF,

4.7pF, ISpF, 47pF. 180pF, 47OpF, 1.8nF, 4.7nF, and 18nF
capacitance sources, 1.8@, 18@,180@, 1.8mS. and 18mS
conductance sxxces and two female-to-female BNC bar­rels. These sources will cabie calibrate all Model 590
ranges (2pF, 20pF, 200pF, and 2nF), and they can also be
used for standard instrument calibration of the 2pF
through 2nF ranges.

Model 5907 Calibration Sources: Includes 470pF and

1.8nF capacitance calibration sources and two femaie-to-

Manual or semi-automatic probe station equipped with:

l

Microscope

. Micropositioners

l

Coax probe tips

l

IEEE-488 interface (for programmable positioning)

Contact the Keithley Instruments, Inc Applications De-.
partment for recommendations on these items.

l-5

SECTION 1

General information

1.9.6 Switching Equipment

Optional switching equipment is used for multiple de­vice testing using BTS and Zerbst test sequences. The fol­lowing paragraphs summarize recommended switching
mainframes and cards. Table 1-8 summarizes recom­mended switching equipment and important specifica­tions.

Switching Mainframes

Model 705/706 Scanners: The Model 705 Scanner pro­vides two-card switching capability with up to 20 chan­nels or 40 crosspoints per mainframe, while the Model
706 can switch 100 channels or 200 matrix crosspoints per
mainframe. Both the Models 705 and 706 have a standard
IEEE-488 interface which allows automated control of
switching functions associated with Model 5958 systems.
Cards which can be used with the Models 705 and 706 in­clude 705X and 715X cards discussed below.

Model 707 Switching Matrix The Model 707 Switching
Matrix can accommodate up to six compatible 707X or
717X cards (see below). The Model 707 has a standard
IEEE-468 interface and can store up to 100 relay setups,
simplifying system configuration. Separate analog back­planes assure that maximum signal integrity is main­tained.

Switching Cards

solution for high-frequency C-V switching of up to five
DUTS.

Model 7152 Low-Current 4 x 5 Matrix Card: The Model
7152MatrixCardis organizedas a4rowby5 columnma­trix and provides l-pole, low-current switching suitable
for general-purpose I-V/C-V applications.

Model 707 Switching Cards

Model 7072 Semiconductor Matrix Card: Organized as

an 8 x 12 matrix, the Model 7072 provides two paths for
high-hequency C-V measurements, two paths for sub­picoamp I-V measurements, and has four general­purpose paths. The Model 7072 is recommended for gen-

eral I-V/C-V applications. NOTE: optional Model
707%TRX-BNC triax-to-BNC adapters (one per path) are
required to connect BNC cables to the Model 7072.

Model 7073 Coaxial Matrix Card: The Model 7073 is or­ganized as an 8 x 12 matrix and provides l-pole, 5OQ
switching on each path. The Model 7073 is recommended
for BTS parallel switching.

Model 7074D/7075 Multiplexer Cards: Each Model
7074D/7075 has eight 1 x 12 multiplexer banks, which
can be combined in several multiplexer configurations
uptolx96.

Model 705/706 Switching Cards

Model 7062 RF Switch Card: The Model 7062 has two in­dependent 1 of 5 switches and provides an inexpensive

l-6

Model 7173-50 Two-Pole High Frequency Matrix Card:
The Model 7173 provides 4 rows by 8 columns of 2-pole,
5OQ switching, and is ideal for high-frequency C-V app!i­cations except where parallel switching is required.

Table l-8. Switch Selection Table for Model 5958 Tests

General

SECTION 1

Information

Zerbst Sequence
BTS Sequential
BTS I’arallel
Bandwidth
Stray Capacitance
Shunt Capacitance
Offset Current

Maximum Voltage
Maximum Current

Connection Scheme

DUTs per Card
M&fraIW

7062

X
X

5ooMHz

no spec
no spec
no spec

24V

5omA

BNC

705:706

7152 7075 7056 7073 7173 7072’

X
X X X
X X

6OMHz 3OMHz

<lpF <3pF

<lOOpF

<lpA <lOOpA

zoov 1lOV 150v

X X

X

1OMHz

<20pF

<lOOpF <50pF

-

X
X
X

3oMHz

0.3pF

220pF

lOpA typ

2oov

X
X

3ooMHz

<O.O4pF

150pF

<200pA

3ov

5-15MHz

0.4-IpF
no spec

A, B, 1pA

G, H 20pA

HV:l.lkV

IA

vi-series/

BNC
2-2.5

705/706

1A

Sub-D/

Dress

Cable

48

707

25OmA

Screw

TfXIXlini

5

705/706

I

1A

BNC

Common

LO

6

707

0.5A
BNC

T&U/

6

707

X
X
X

2oov

1A

3-lug

BNC

6

707

l-7

SECTION 2

Getting Started

2.1 INTRODUCTION

This section includes introductory information on get-

tingyourModel5958softwareupandrtmningasquickly
as possible. For details on test setup, measurement, and
analysis, refer to Sections 3,4, and 5 respectively.

Section 2 contains the following:

2.2 IEEE-488 Bus Considerations: Gives an overview of
IEEE-488 interface installation, bus connections,
and primary address.

2.3 Software Installation: Details software backup and
installing the software on your hard drive.

2.4 Test Connections: Shows BTS and Zerbst test con­nections as well as connections for the optional
Model 230-l Voltage Source and matrix card.

2.5 Cable Correction: Covers the cable correction pro­cedure necessary to optimize measurement XCU­racy.

2.6 Running the Software: Covers running the soft­ware, menus, as well as run time considerations.

2.2 IEEE-488 BUS CONSIDERATIONS

The following paragraphs discuss computer IEEE-488 in­terface card installation, bus connections, and primary
address.

2.2.1

AT Interface Card Installation

Model 5956 can be used with AT and compatible comput­ers and the following IEEE-488 interfaces:

l

IOtech GP488, GP488A, and Power488

l

National Instruments I’CII, I’CIIA, and PC111

l

Keithley Instruments PC-48%CEC and 4-488~CEC

l

Capitol Equipment Corp. PC-488 and 4-488

. IBMGPIB

Before installation, note the following interface board
settings so that you can properly configure the bus driver
software during driver software installation:

l

I/O port address

. DMAstatus

l

Interrupts

l

System controller

Interface Card Installation

2.7 Test and Measurement Overview: Provides an

overall summary of how to perform C-V, C-t, and
BTS tests and analyze the results.

Afternoting thesesettings,install theinterfacecard in the
computer. Refer to the documentation supplied with the
card for detailed installation procedures.

2-l

SECTION 2
Getting Started

PSL? Interface Installation

Model 5958 supports l’s/2 computers with the following
IEEE-488 interface:

l

IOtech GP488/2

The I’S/2 compatible IEEE-488 interface card should be
installed in the computer using the manufacturer’s in­structions. Refer to the interface card documentation for
IEEE-488 bus driver installation instructions and infor­mation on using the IBM I’S/2 computer reference disk­ette.

2.2.2

Bus Connections

For proper operation, the Model 590 C-V Analyzer, hot
chuck, and Model 230-l Voltage Source and switching
mainframe (if used)

must

be connected to the computer
IEEE-488 interface. Shielded IEEE-488 cables, such as the
Model 7007, should be used for bus connections to mini­mize electrical noise, which

could

affect Model 5958

measurements.

Figure 2-l shows typical IEEE-488 bus connections be­tween the computer, the Model 590 C-V Analyzer, and

the optional Model 230-l Voltage Source. Bus connec­tions to the hot chuck and switching matrix interface are

similar.

2.2.3 Default Primary Address Settings

The default primary address of each device associated
with the Model 5958 is as follows:

. Model 590 C-V Analyzer: 15
. Temptronic 0315B Thermochuck: 9
. Optional Model 230-I Voltage Source: 13

You can select other addresses for the Models 590 and

230-I during installation. The thermochuck primary ad-

dress is defined in the hot chuck control file (see Section

6).

If a switching mainframe is used, the primary address
must be that same as specified in the user-defined switch

control file (see Section 6). Also, any other devices con-

nected to the same IEEE-488 bus must not use any of the
primary addresses listed above. Each device on the bus
must have a unique primary address.

Figure 2-1.

2-2

Optional Model 23

Voltage source

Model 590

c-v Analyzer

IEEE488 Bus Connections

TO HO, Chuck

and/or Switching

Matrix IEEE-488

meriacs

/

Model 7007-Z Shielded

Cable (3rn)

Model 7007-Z

Shielded Cable Wnl

connect 10

^~~~

IBM. AT, Psi2 (or

compatible) Cornput

2.3 SOFTWARE INSTALLATION

SECTION 2

Getting Started

Place the installation disk in drive A: or B:, then type:

1.

2.3.1 Software Backup

Before installing the software on your hard disk, it is
strongly recommended that you make backup copies of
each of the disks supplied with the Model 5958. Use the
DOS DISKCOPY command to make copies. For two­floppy disk systems, the general command syntax is:

DISKCOPY A: B: <Enter>

Here, the source disk is assumed to be in drive A, and the
target (copy) disk is in drive B. (Note that DISK COPY can

be used only for the same type of drives; use COPY *.’ for
dissimilar drives.)

Similarly, the command for single-floppy drive systems
is:

DISKCOPY A: A: <Enter>

After copying all supplied disks, put the original disks
away for safekeeping.

2.3.2 Installation Procedure

Follow the appropriate procedure below to install the
Model 5958 software on your hard disk. The following
paragraphs discuss using INSTALL.EXE to install the
software.

NOTE
INSTALL.EXE can also be used to reconfigure
the software after installation. Select the
reconfigure option to change an existing soft­ware configuration. (You can also run
EQUIP.EXE after installation to select graph­ics and printer/plotter configurations.) You
should have at least 5MB of free disk space
prior to installing the Model 5958. (You can
save some disk space by choosing not to in­stall source files during installation if they are
not needed.)

A: <Enter>
or
B: <Enter>

2. Type the following to start the installation process:
INSTALL <Enter>
Follow the prompts on the screen to select the dlrec-

3.
tories for the various files and programs. You can se­lect installation defaults, which are summarized in
Table 2-1, or your own directory names, as desired.
You can also choose not to install source files if de­sired (source files are required only if you intend to
modify the program).

4.

Select whether or not you are using a IModel 82 Si­multaneous C-V System. NOTE: refer to Appendix
H for further considerations when using a combined
Model 82/5958 system.

5.

Next select whether an option Model 230-I Voltage
Source, hot chuck, and switching mainframe are pre­sent in your system.

If you are using a Model 230-1, select whether or not

6.
you will be using a light to speed up equilibrium.

(Refer to paragraph 2.4.4 for light connections.)
Indicate whether your Model 590 C-V Analyzer has

7.

1OOkHz and/or 1MHz options.

8.

Choose the lime printer. Note: this selection affects

only text print-outs. Graphics printer operation is se­lected separately (see below).

9.

Be sure to select the correct Model 590 and Model
230-l primary addresses (only if you are not using a
Model 82 system).
Continue the installation process by selecting appro-

10.
priate graphics cards, printers, and plotters at the ap­propriate prompts. Table 2-2 summarizes graphics
cards, and Table 2-3 lists supported printers and
plotters. Also, refer to paragraph 2.3.5 below for cer­tain plotter and printer considerations.

NOTE
The Model 5958 will run properly on most
VGA, Super VGA, and 8514 monitor com-

wter svstems in the EGA mode. To use the
bode1 $958 with any of these graphics sys­tems, select the EGA graphics mode at the ap­propriate prompt.

2-3

SECTION 2
Getting SLurted

Table 2-1. Default Directories

Sub-directory
C:\KTHLY-CV\MODEL%
C:\KTHLY_CV\MODEL58\CAL

C:\KTHLY_CV\MODEL58\CTRL
C:\KTHLY_CV\MODEL58\DAT
C:\KTHLY_CV\MODEL58\PAR
C:\KTHLY_CV\MODEL58\SEQ
C:\KTHLY_CV\MODEL58\SRC
C:\KTHLY_CV\MODEL58\TMP
C:\IEEE488

Graphics Board Mode

IBM color board
Tsent EVA
Tecmar Graphics Master

Hercules Monochrome
Enhanced Graphics Adapter (EGA)
T&Video AT
TeleVideo HRCGB
Sigma Color 400
AT&T 6300
Corona PC
Corona PC400
Corona ATP

HP. Vectra
T.1 Professional
Genoa SuperEGA HiRes
IBM VGA*

* Sdect EGA mode

Table 2-2.

contents
KI5958CV.EXE, configuration file, CONFIG.GPC, .FNT or other

files needed by KI5958CV.EXE, CABLECAL.EXE
Cable calibration data files, ‘.CAL
Switch control and hot chuck control files, ‘SWC and *.HCC
Data destination files, ‘.DAT and *.CTD
C-V, C-t, and stress cycle parameter files, *.CVP, *.CTl’, and ‘.SCP
BTS and Zerbst test sequence files, *.BTS and “.ZTS
Source code, library, and utilities to rebuild.
Temporary files used for program communication.*
IOtech Driver488 GPIB interface driver software*

Supported Graphics Cards

Resolution

monochrome

monochrome
16 color
monochrome
16 color
monochrome
16 color
16 color
native graphics
native graphics
native graphics IBM emulation 640 x 400
monochrome
monochrome
monochrome
16 color
16 color
monochrome

640 x 200

640 x 480
720 x 700
640 x 400
720 x 348

640 x 350

640 x 400

640 x 400
640 x 400
640 x 400
640 x 325

640 x 400
640 x 400
720 x 300
800 x 600
640 x 480
640 x 480

2-4

SECTION 2

cettim Started

Table 2-3.

Printer/Plotter

C. Itoh Prowriter; NEC 8023,8025
Epson FX, RX; Cannon BJSO
Okidata 92,93
IBM Graphic or Professional; Epson MX
Tektronix 4695 ink jet printer
Toshiba P321 and P351 (unidirectional printing)
Corona Laser Printer (requires extra 128K memory)
Houston DMP-XX plotters
Hewlett-Packard HP-GL plotters
C. Itoh 24LQ
Watanabe Digi-Plot plotter
Epson LQ-1500
Smith Corona DlOO
Epson HI-80 plotter
Hewlett-Packard LaserJet+ (or compatible)
Micro Peripherals 150,180
Okidata 192+ (8-bit graphics)
CALCOMP ColorMaster
Toshiba 1340 (no unidirectional)
HI’ ThinkJet (SW5 up, 6.5 X 8.5 in.)
Roland DXY-800 plotter
Toshiba P351C with color ribbon
NEC Pinwriter l’ series
Quadram QuadLaser (with vector software)
NEC Pinwriter P series (with color ribbon)

Supported Printers and Plotters

NOTE

After modifying CONFIGSYS, reboot the
comDuter (Dress<Ctrl>-<Alt>-<Del>) to place

the changes into effect.

2.3.5

Printer Hard Copy Resolution
Selecting a plotting option on the graphics menu gener-

ates a half-page plot with low resolution. To control the
size and resolution of the plot from the graphics menu,
type in one of the following letters:

Selecting one of these options automatically generates

the corresponding plot.

Plotter support

Model 5958 supports Hewlett-Packard, Watanabe,
Houston, and Epson pen plotters that use the HP-GL
graphics language. For HP plotters not listed in the con­figuration menu, first try one of the listed plotters. For ex­ample, select 7475A for 7470A.

Plotter and Printer Considerations

“m” half page, low resolution
“M” half page, high resolution
“I” full page, low resolution
“L.” full page, high resolution

2.3.3 IEEE-488 Driver Software
Installation

The driver software for the IEEE488 interface card
should be installed per manufacturer’s recommenda-

tions. Refer to the IEEE-488 driver software documenta-

tion for complete details.

2.3.4 CONFIG.SYS Modification

For most computer configurations, you should assign at

least 20 buffers and files in CONFIG.SYS. Use a text edi-

tor to modify or add the following lines:

FILES = 20
BUFFERS = 20

Serial Printer and Plotter Support

Model 5958 will drive printers or plotters connected to
either the serial or paiallel port of your computer. If you
are using the serial port, you must initialize the port by
selecting the proper parameters for your particular serial
connection during installation or reconfiguration. For
Hewlett-Packard serial plotters, select eight data bits and
one stop bit serial parameters.

The graphics routines use polling to send characters to

the serial port. Polling means that a character is sent, and

a check is made to see if the device is busy. If so, the mu-

tine waits until the device is ready to accept another char­acter. However, if the serial port device sends back any
character other than busy, the transmission sequence will
be interrupted. For that reason, be sure to set your printer

or plotter to its least intelligent mode (turn off handshak-

ing and status reports). Also, be sue to use the proper se-

rial cable, as the software requires that all serial signal

lines be present.

2-j

SECTION 2
Gettin&! Stuarted

Laser Printer support

Model 5958 supports a Hewlett-Packard LaserJet+ or
compatible printer with full-page 300dpi resolution.
However, the printer must be equipped with at least

1.5MB of memory to support this resolution. In addition,
some computer configurations may not have enough
memory to support the required large bit map. In those
cases, an “m” (300dpi, l/2 page) or “I” (150dpi, full page)
plot can be performed.

GPIB (IEEE-488 Bus Plotter Support)

A GPIB HP-GL plotter can be used with the Model 5958

by selecting the “output to Driver 488 plotter” option on

the configuration menu. The plotter must be set for the
addressable mode using a primary address of 5.

Note that a GPIB printer cannot be used.

2.3.6 Memory and Hard Disk
Considerations

Your computer should have at least 400KB free base
memory before running the software. Also, you should
have at least 5MB of free hard disk space prior to installa­tmn.

it is recommended that the entire probe station be
mounted in a suitable metal enclosure which is electri­cally connected to C-V Analyzer OUTPUT and INPUT
LO. (Mounting chassis-mount BNC connectors on the en­closure chassis will electrically connect the enclosure to
LO.)

WARNING
Connect the shielded enclosure to safety
earth ground using MSAWG or larger wire

before use.

NOTE
Connections for the hot chuck, which is re­wired for BTS measurements. are not shown
h Figure 2-2. Refer to the instruction manual
for the hot chuck equipment for operating de­tails pertaining to that equipment. Note, how­ever, that some hot chuck.? connect chassis
ground to the chuck. In that case, setup the
Model 590 for floating operation (set rear
panel ANALOG COMMON GROUNDING
switch to the ungrounded position.)

When making C-V analyzer connections, keep the fol­lowing points in mind:

2.4 TEST CONNECTIONS

2.4.1

Figure 2-2 shows typical connections between the Model
590 C-V Analyzer and a probe station. To minimize noise,

2-6

C-V Analyzer Connections

Use only 5OQ coaxial cables of good quality.

Keep cable lengths as short as possible.
Use the minimum number of connectors possible.
Perform cable correction before making measure­ments (paragraph 2.5).
Connect INPUT to gate, OUTPUT to substrate to mini­mize noise.

SECTION 2

Gdtinv Started

Figure 2-2.

2.4.2

Typical C-V Analyzer Connections

Optional Voltage Source 2.4.3
Connections

AnoptionalModel230-1 VoltageSourcemay beuse with

the Model 5958 system to extend the voltage range to

k1OOV. Figure 2-3 shows connections between the op-

tional Model 230-I Voltage Source and the C-V Analyzer.

In addition to the source connecting cable, a BNC short­ingcap (Mode14851) must be connected where indicated,
and the external trigger cable must also be in place.

WARNING
Hazardous voltage may be
nals when the Model 230-l Voltage Source is
connected to the system.

present on

termi-

Typical Switching Card
Connections

Amatrixcardorscannercard andaswitchingmainframe
can be added to a Model 5956 test system to perform
automatic test sequencing. Figure 24 shows typical con­nections between the Model 590 and a Model 7062 RF
switch card, which can be used to switch up to five Dolts.
FigureZ-5 shows typical connections using a Model
7173-50 Two-Pole High Frequency Matrix Card installed
inaModel707SwitchingMainframe.Seeparagraph4.5.1
for more details on switch connections.

NOTE
In order to use a switching mainframe, you
must first configure an appropriate switch

control

control files. Section 6 discusses switching
control in detail. Appendix J covers default
switch control files supplied with the Model

5958.

file or use one of the supplied switch

2-7

SECTION 2
Getting Started

Optional Voltage Source Connections

‘igure 24.

2-8

RF Switch Card Example

Model

590 C-V A

el 707 Switchino

-

=
3

SECTION 2

Gettim Started

Model 590 C-V Analyzer

A. Connections

II2

-

3

-

-

-

Typical Matrix Card Connections

6. Equivalent Circuit

2-9

SECTION 2
Getting Started

2.4.4

A user-supplied light can be connected to a system
equipped with an optional Model 230-I Voltage Source

to help attain device equilibrium in inversion more rap­idly. This light is controlled through terminals on the
Model 230-l Digital I/O port. The following paragraphs
discuss terminal assignments and typical light connec-

tions.

Digital I/O Port Terminals

Table 2-4 summarizes Model 230-l Digital I/O Port As-

signments, and Figure 2-6 shows the terminal arrange-

ment for the mating edge connector (Keithley part num-

ber CS-444-1). Note that pin 10 is used for controlling an

external light. This output is LS-TTL compatible and can

sink a maximum of 8mA. Logic convention is such that

the light is on when the output is LO, and the light is off

when the output is HI.

rennina

Light Connections

Table 2-4. Model 230-l Digital I/O Port

Terminal Assignments

Description

Model 230-l

Digital l/O Port

123456

12

11 10 9 8 7

I

NOTE: Mating edge connector rear view

(Part # cs-444-1)

I

Figure 2-6. Model

LED Connections

The digital output has sufficient drive capability to di­rectly drive LEDs that draw up to 8mA using the connect-

ing method shown in Figure 2-7. The anode of the LED
should be connected to +5V, and the cathode of the LED
should be connected through a 39OQ current-limiting re­sistor to the light control bit (pin IO).

230-I

Voltage

Port Terminal Arranwnent

Source Digital l/C

1
2
3
4
5
6
7
8
9

10
11
12

c5v
+5v
Input (Bit 3)
Input (Bit 2)
Input (Bit 1)
Input (Bit 0)
Output (Bit 0)
Output (Bit 1)
Output (Bit 2)
Output (Bit 3), Light Control Bit*
Digital Common
Digital Common

Figure 2-7.

Direct LED Control

Z-10

SECTION 2

Getting Started

Relay Light Control relay coil resistance. For example, with a supply voltage

of 5V, a coil resistance of 5OOI2, and a transistor current
For large LEDs, or for smallincandescent lamps, an exter­ml relay control circuit can be used to switch the larger

gain of 100, a base resistor value of lo!42 shouid be low

enough to drive the transistor well into saturation.
current. Figure 2-8 shows a typical circuit, which requires

a normally closed relay contact. Note that an external

power supply is necessary to supply the external cir-

cuitry.

Note that the diode across the relay coil should be in­The value of the base resistor will depend on the current

gain of the transistor, the power supply voltage, and the

eluded to protect the transistor from switching han-

sients.

+V (External Power supply)

P

MOdd 230-I

Voltage Source

Digital l/O Port

Figure 2-8. Relay Light Control

2-11

SECTION 2

Getting Started

2.5 CABLE CORRECTION

Cable correction is necessary to optimize accuracy of
high-frequency C-V measurements by compensating for

cabling effects. Cable correction is especially important
for accurate lMHzmeasurements, but it canalso be bene­ficial when making 1OOkKz measurements.

The process involves using the CABLECAL.EXE utility

and connecting calibration capacitors with precisely
known values in place of the test fixture or probe station.
Once ~orrectlon is complete, correction constants are
written to a user-defined file and recalled when tests are
performed.

2.5.1

Cablecorrectionmustbeperformed thetisttimeyouuse
your system. Thereafter, you should cable correct your
system if the ambient temperature changes by more than

SC from the previous correction temperature. You can

cable correct your system daily, if desired, but doing so is

not absolutely essential.

When to Perform Cable Correction

2.5.2 Recommended Correction
Sources

Table 2-5 summarizes the recommended calibration
sources, which are included in one of several optional
calibration capacitor sets (see paragraph 1.9.3 for a de­scription of recommended sources). The values shown
are nominal; you should use the IOOkHz and 1MHz val­ues marked on the sources when performing correction.

2.53

In order to correct your system, it will be necessary for
you to disconnect the Model 590 from the probe station or
test fixture and connect the calibration capacitor in its
place. Figure 2-9 shows typical connections. Use two fe­male-to-female BNC barrels to connect each source to the
cable ends.

When using the sources, be sure not to handle them ex­cessively, as the resulting temperature rise will change
the source values, degrading the accuracy of the correc­tion process.

Calibration Source Connections

Table 2-5.

Model 590 Range

2pF-

20pF

200pF

2ti

’ Nominal values included with calibration capacitor set. See paragraph 1.9.3 for a description of various caiibratlon capacitors.
**Enter values marked an SOUTC~S where indicated. Use actual source values when performing cable correction using CABLECALEXE.
‘** IOOkHz test frequency only

Nominal Value*

0.5pF

1.5pF

4.7pF
18pF

47pF

180pF

470pF

1.8nF

Cable Correction Sources

lOOkI& Value’* 1MHz Vah?

2-12

Output

SECTION2

Getting Started

Figure 2-9.

2.5.4

The procedure outlined below uses the
CABLECAL.EXE utility,which is discussed in

detail in Appendix E.

1. While in the C:\KTHLY_CV\MODEL58 directory,
type in the following to run the cable calibration $il­iiy :

CABLECAL <Enter>

2. To load an existing calibration constants file, press
<Alt>-F, then select Load on the menu. Select an ex­isting file, or type in the name of the file.

3. Press <Alt>-E, then select Cable Cal 590 and the de­sired range.

4. If you are cable correcting your system for the first
time, enter the nominal, IOOkHz, and IMHz values
where indicated (use the <Tab> key to move around
seiections). Capacitor #1 is the smaller of two values,
and Capacitor #‘2 is the large capacitor value for a
given range. Select OK after entering source values
to begin the calibration process.

5. Choose the CALIBRATE selection to perform com­plete cable calibration.

6. Follow the prompts on the screen to complete the
calibration process. During calibration, you will be
prompted to connect calibration capacitors, or to
leave the terminals open in some cases. If any errors
occur, you will be notified by suitable messages on

the screen.

7. Repeat steps 3 through 6 for all Model 590 ranges to
be cable corrected.

8. After calibration is complete, you must save the new
calibration constants. To do so, Press <AIt>-F, then

Calibration Source Connections

Correction Procedure

NOTE

seiect Save or Save As as required. If you use Save
As, be sure to use a filename with a .CAL extension.

Use the same filename when specifying the cable
correction filename while setting up your tests (refer
to Sections 3 and 6).

NOTE

Be sure to save cable calibration files in the

C:\KTHLY_CV\MODEL5A\CAL directory.

2.5.5

Optimizing Correction Accuracy to

Probe Tips

To correct as close as possible to the probe tips, construct
two 5OQ coaxial cables equal in length to the probe sta­tion cables connected between the BNC connectors and
the probe tips. Connect those cables in place of the probe
station,andperformthecablecorrectionprocedurelisted
in paragraph 2.5.4.

2.5.6

Cable Correcting Switching
Pathways

If you intend to use switching for multiple or sequential

tests, you should cable correct the entire pathway

throughtheswitchandasclose to theprobestationor test
fixture as possible. If multiple pathways are to be used,
correction should be performed for each pathway indi­vidually, and each set of correction constants should be
saved under its own filename. In some cases, a single cali-

bration will suffice. Contact the Keithley Applications

Department for detaiis. Remember to close all channels

or crosspoints in a given pathway when performing cor-

rection. Also, be sure to enter each cable correction file-

name in the switch control file (see Section 6).

2-13

SECTION 2
Getting Started

2.6 RUNNING THE SOFTWARE

The following paragraphs discuss the basic procedures

for running the Model 5958.

2.6.1 Starting the Program

To execute the program from the main menu, simply

type in the program name (KI5958CV) while in the
C:\KTHLY_CV\MODEL58 subdirectory. For example,
to load and run KI5958CV from the DOS prompt, simply

type:

KI5958CV <Enter>

NOTE

The program to be executed must be located

in the current default directorv to run. Previ­ous parameter setup and data files will be
automatically loaded at run time.

2.6.2 Default Paths

Normally, the Model 5958 software uses the default
paths specified during installation for parameter and
data files. If you specify a new path when loading or sav­ing files, the new path will become the default path for
the current session.

2.6.3 Run Time Considerations

I” order to use Model 5958 properly, it may be necessary

to remove software drivers (such as GPIB print or mouse
drivers) from your computer configuration to free up
enough memory or to avoid conflicts. Use EDLIN or
other text editor to remove the driver installation state­ments from CONFIG.SYS or AUTOEXEC.BAT as re­quired. Reboot your computer after making modifica­tions before running the Model 5958 software.

2.6.4

Menu Title Bar

Major menu selections will appear in the menu title bar at
the top of the screen. You can select one of these menu
items using one of two methods:

Hold down the <Alt> key, and press the highlighted
letter, or use the left or right arrow keys to highlight
the desired selection, then press <Enter>.
If you are using a mouse, simply move the mouse to
place the cursor on the desired selection, the” click the
appropriate mouse button. (Usually, the left mouse
button selects a” item, while the right mouse button
performs the escape function.)

Using Keys to Move Around Menus

Use the following keys to move around a menu and make
selections:

Up/down arrow keys: Use these keys to move cursor
vertically. Pressing up arrow or down arrow also en­ters a new numeric value if that value was changed.
Left/right arrow keys: Use these keys to tab the cursor
to another selection on a line that has multiple selec­tions and to move the cursor within a numeric or file
name field while entering parameters.
<Tab>: Use the <Tab> key to tab to the right for multi­ple selections on a line. Press <Shift> <Tab> to tab to

the left.
<Enter> key: Press <Enter> to complete numeric pa­rameter or file name entry.
<Space> key: Press <Space> to toggle menu button se­lections on or off.
<Eso: Press <Eso to close a window or pull-down

menu.

Using a Mouse to Move Around Menus

Move the mouse to place the cursor on the desired item,
then click the approproate mouse button.

Selecting Menu Items

Also, be careful not to touch Model 590 front panel but­tons while a program is running. Doing so may change
instrument settings and lead to erroneous results.

2-14

The Model 5958 may be used with a Microsoft mouse (or
compatible) as long as memory or other conflicts do not
occur.

SECTION 2

Getting Started

2.6.5

Main Menu Description

Setup

The Setup selections allow you to program parameters

for the various tests. Setup selections include:

. c-v
. c-t

l

BTSCycle

l

BTS Sequence

l

Zerbst Sequence

For complete details on setting up tests, refer to Section 3.

RlUl

The Run selection allows you to choose the type of test to
run. Note that you must use the corresponding Setup pa­rameter menu to select measurement parameters before
running each test.

Run menu selections include:

l c-v
. c-t

l

BTSCycle

l

BTS Sequence

l

Zerbst Sequence

Refer to Section 4 for detailed information on using these
selections to make measurements.

Analyze

The Analyze selection allows you to perform analysis on
data taken during measurements. Operations available
under Analyze include file I/O, displaying data, printing
data, as well as graphing data. The three general types of
data analysis are:

l c-v
. c-t
l

BTS

Analysis is covered in detail in Section 5.

Exit

l

Exit to DOS

Selecting this main menu item will return you to DOS.

2.6.6

File Types

The various file types for parameters, data, and control

information are summarized in Table 2-6. Appendix D
gives more detailed information on these files and their
formats.

Table 2-6. File Types

File

BTS test sequence file
Cable calibration file
c-v measurement parameters file
c-t measurement parameters file
C-t data destination file
C-V data destination file
Hot chuck control file
Stress cycle parameters file

Switch control file
Temporary file
Zerbst test sequence file

* All path names are preceded by C:KTHLY~cv\MODEL58 as the default path. You can select
different path names during installation, ii desired. Refer to paragraph 2.3 for installation details.

i

Extension

.BTS
.CAL
.CVP
.CTP

.CTD
.DAT

.HCC

scr

swc
.TMP

2.X

Default Path*

\SEQ
\CAL
WAR
WAR

\DAT
\DAT

\CTRL

WAR

\CTRL

\TMP

\SEQ

2-15

SECTION 2

Grtting Started

2.6.7

Running with Floppy-Based Test/
Data Files

Normally, test and data files are run from subdirectories
summarized in Table 2-6. You can, however, load this in­formation from suitable files stored on floppy disks sim­ply by specifying the complete pathname at filename
prompt for the load operation.

For example, assume that you wish to load a data file
called “MYFILE.DAT” from drive A:. You would simply

type in the following at the load file prompt:

A:\MYEILE <Enter>

2.6.6

You can print out any screen that contains only text infor­mation simply by pressing the Print Screen key.

Printing Screens

l

Run the IU5958CV program, as covered in paragraph

2.6.

2.7.1 C-V Measurement Overview

Step 1: Setup C-V Measurement Parameters

From the main menu, press <Ah>-S, and select C-V
setup to dispiay the C-V parameters menu.
Select the various measurement parameters such as
range, frequency, model, and rate, as required. Use
the up/down and left/right arrow keys to move
around the parameter screen.
Choose the waveform type and various time/delay
parameters. Remember to use a step time long
enough so that the device remains in equilibrium
throughout the sweep. Also, you should be certain to
program a sufficiently long start delay time to aHow
the device to reach equilibrium before the sweep be­gins when sweeping from inversion to accumula-

tion.

2.6.9 Default Material Constants

As shipped, the Model 5958 software is designed to work
with devices with silicon substrate, silicon dioxide insu­lator, and aluminum gatematerial. Constants that define
these and other parameters are stored in the
MATERIAL.CON file, which can be modified for use
with other types of materials. See Appendix A for details.

2.7 TEST SETUP, MEASUREMENT AND
ANALYSIS OVERVIEW

The following paragraphs outline the basic procedures
for performing tests and viewing the results. For
plete details on test setup, measurement, and analysis, re­fer to Sections 3,4, and 5.

Before attempting to make any measurements using the
Model 5958, you should complete the following:

l

Install the software, as described in paragraph 2.3.

l

Connect the Model 590 to the computer and probe sta­tion (paragraph 2.4).

l

For BTS measurements, install the hot chuck and con­nect it to the computer IEEE-488 interface (refer to hot
chuck manual).

l

Perform cabie correction, as discussed in paragraph

2.5.

com-

Briefly, time parameters are defined as follows:

Start Delay: An additional d&y period at the begin­ning of the first bias step.

Step Time: The time period for each bias step for stair
waveform.

Pulse On: The on period of each pulse for pulse stair
waveform.

Stop Delay: An additional delay period at the end of
the sweep.

Pulse Off: The time period between pulses for the
pulse stair waveform.

Enter the bias voltage parameters necessary to bias
the device into accumulation and inversion during
the sweep. Briefly, bias voltage parameters are de­fined as follows:

First Bias V: The first DC bias voltage step value and
the bias applied before the sweep.

Bias Step V: The incremental change in the bias volt­age waveform.

Last Bias V: The last DC bias voltage step value.
Default Bias V: The DC bias voltage applied to the

device after a sweep.

2-16

SECTION 2

Getting Started

If you have a light connected to your system, pro­gram the desired light on time.
Enter the cable calibration filename where indicated
(see paragraph 2.5 for cable calibration details).
After you have entered all your parameters, select
Save, then enter the desired filename at the prompt.
Select OK to return to the main menu.

Step 2: Perform a C-V Measurement

1.

From the main menu, press <Alt>-R, then select C-V.

2.

Make sure that the probes are up and that zero is
hxned off.

3.

Allow the reading to settle, then select Enable Zero
to null any offsets in the system.

4.

Place the probes down on the test dots.

5.

If you are using a light to speed up equilibrium, se­lect Enable Light. Turn the light off after equilibrium
is reached before starting the sweep.

6.

Select Start Sweep to begin the sweep. During the
sweep current measurement parameters will be dis-

played, and you can press any key to halt the sweep.

7.

After the sweep is completed, return to the main
IIlWZl”.

Step 3: Analyze C-V Data

Choose the various time/delay parameters. Briefly,
time parameters are defined as follows:

Start Delay: An additional delay before the first sam­ple in the C-t measurement is taken before the sweep
begins and the voltage changes.

Sample Time: The time period between individual
sampies in the C-t measurement.

Stop Delay: An additional delay after the last sample
before the end of the C-t meaxuement cycle.

Enter the bias voltage parameters necessary to bias
the device as required both before and during the
sweep. Briefly, bias voltage parameters are defined
as follows:

Default Bias V: The DC bias voltage applied to the
device both before and after the C-t measurement.

Test Bias V: The DC bias voltage applied to the de­vice during the C-t measurement.

Enter the cable calibration filename where indicated
(see paragraph 2.5 for cable calibration details).
After you have entered all your parameters, select
Save, then enter the desired filename at the prompt.
Select OK to return to the main menu.

From the main menu, press <Alt>-A, then seiect
c-v.
Return to the C-V Analysis menu, then press
<Al&D to display data arrays or constants. You can
also use <Alw> to print array values or constants on
your printer.
To graph C-V data, press <Alt-G> while in the C-V
ANALYSIS menu. Typical C-V graphs include C vs.
V and G vs. V.

2.7.2

Step 1: Setup C-t Measurement Parameters

1. From the main menu, press <Alt>-S, and select C-t

2. Select the various measurement parameters such as

3. Enter the number of samples to take for the C-t meas-

C-t Measurement Overview

setup to display the C-t parameters menu.

range, frequency, model, and rate, as required. Use
the up/down and left/right amow keys to move
around the parameter screen.

urement.

Step 2: Perform a C-t Measurement

1.

From the main menu, press <Alt>-R, then select C-t.

2.

Make sure that the probes are up and that zero is
turned off.

3.

Allow the reading to settle, then select Enable Zero
to null any offsets in the system.

4.

Place the probes down on the test dots.

5.

If you are using a light to speed up equiiibrium, se­lect Enable Light. Turn the light off after equilibrium
is reached before starting the sweep.

6.

Select Start Sweep to begin the sweep. During the
sweep current measurement parameters will be dis­played, and you can press any key to halt the sweep.

7.

After the sweep is completed, return to the main
menu.

Step 3: Analyze C-t Data

1. From the main menu, press <Ah>-A, then select C-t.

2. Return to the C-t Analysis menu, then press <Alt>-D
to display data arrays or constants. You can also use
<Alt-P> to print array values or constants on your
printer.

2-17

SECTION 2
Getting %arted

3. To graph C-t data, press <AIt-G> while in the C-t
ANALYSIS menu. Typical C-t graphs include C vs. t
and Zerbst analysis.

2.7.3 BTS Measurement Overview

Step 1: Setup C-V Measurement Parameters

1.

From the main menu, press <Ah>-S, and select C-V
setup to display the C-V parameters menu.

2.

Select the various measurement parameters such as

range, fxquency, model, and rate, as required. Use
the up/down and left/right arrow keys to move

around the parameter screen.

3.

Choose the waveform type and various time/delay

parameters. Remember to use a step time long

enough so that the device remains in equilibrium

throughout the sweep. Also, you should be certain to

program a sufficiently long start delay time to allow

the device to reach equilibrium before the sweep be­gins when sweeping from inversion to accumula-

tion.

Briefly, time parameters are defined as follows:

Start Delay: An additional delay period at the begin­ning of the first bias step.

Step Time: The time period for each bias step for stair
waveform.

Pulse On: The on period of each pulse for pulse stair
waveform.

Stop Delay: An additional delay period at the end of
the sweep.

Puke Off: The time period between pulses for the

pulse

stair

waveform.

6. Enter the cable calibration filename where indicated
(see paragraph 2.5 for cable calibration details).

7. After you have entered all you parameters, select

Save, then enter the desired filename at the prompt.

8. Select OK to accept parameters and
main menu.

Step 2: Program BTS Stress Cycle Parameters

From the main menu, Press <AIt>-S, then select BTS
Cycle.
Select the 590 Internal bias source if you are using
only the Model 590, or select the 230-l External bias
sourceif youareusinganoptionalModel230-I Volt­age Source.
Program the + Stress V, -Stress V, and Stress OFF V
parameters to the desired values. Briefly, these pa­rameters are defined as follows:

+ Stress V: Voltage applied to device during the posi-

tive stress cycle.

-Stress V: Voltage applied to device during negative
stress cycle.

Stress OFF V: Voltage applied to device during stress

off cycle.

Enter the desired stress temperature and stress time

parameters where indicated. These parameters are
defined as follows:

Stress Temp: The temperature of the device during

the stress cycle.

Stress OFF Temp: The temperature of the device at

times other than during the stress cycle.

Temp. Tolerance: At temperature tolerance of Hot
Chuck.

return

to the

4.

Enter the bias voltage parameters necessary to bias

the device into accumulation and inversion during

the sweep. Briefly, bias voltage parameters are de-

fined as follows:

First Bias V: The first DC bias voltage step value.

Bias Step V: The incremental change in the bias volt-

age waveform.
Last Bias V: The last DC bias voltage step value.

Default Bias V: The DC bias voltage applied to the

device both before and after a sweep.

5.

If you have a light connected to your system, pro­gram the desired light on time.

2-18

Stress Time: The time duration of the stress cycle.

5,

Select Save, then enter the filename to save the BTS
cycle parameters.

6,

Select OK to return to the main menu.

Step 3: Program BTS Test Sequence Parameters

1. From the main menu, press <Alt>-S, then seiect BTS
Sequence.

2. Choose the test sequence type: sequential, parallel,
or no stress. The sequential test type runs through
the entire stress-measurement sequence for each de­vice in asequentialmanner, while the parallel test se­quence stresses a number of devices in parallel and

SECTION 2

Getting Started

then measures C-V parameters for each device indi­vidually. The no stress option is used for C-V only
measurements without stress.

3.

Select the stress cycle type: + then -, - then +, + only,
or-only. + then -applies the positive then negative
stress voltages - then + applies negative then posi­tive voltages, while + only and-only apply only the
positive or negative stress voltages respectively dur­ing the stress cycle.
Select the type of Cm checking: manual, auto, or

4.
none. (to select auto, you must have a light con­nected to the optional Model 230-I voltage source.)

5.

Enter any comments in the indicated field.

6.

Program the number of devices based on your test
requirements. In order to test more than one device
automatically, you must have a switching main­frame or probe sequencer that can connect to multi­ple test dots automatically. See Section 6 for informa­tion on setting up a control file for this equipment.
Enter the C-V, stress cycle parameter, and data desti­nation filenames where indicated. These are the files
set up in steps 1 and 2 above. The switch control file­name should also be specified if you are using a
switching mainframe. The data destination filename
defines the storage location for data taken during a
BTS test.
Select Save, then save the BTS stress sequence pa­rameters under a convenient filename.
Select OK to return to the main menu.

Step 4: Run the BTS Test

2.7.4 Zerbst Measurement Overview

Step 1: Setup C-V Measurement Parameters

1.

From the main menu, press <Alt>-S, and select C-V
setup to display the C-V parameters menu.

2.

Select the various measurement parameters such as
range, frequency, model, and rate, as required. Use
the up/down and left/right arrow keys to move
around the parameter screen.

3

Choose the waveform type and various time/delay
parameters. Remember to use a step time long
enough so that the device remains in equilibrium
throughout the sweep. Also, you should be certain to
program a sufficiently long start delay time to allow
the device to reach equilibrium before the sweep be­gins when sweeping from inversion to accumula­tion.

Briefly, time parameters are defined as follows:

Start Delay: An additional delay period at the begin­ning of the first bias step.

StepTime:The time period for each biasstep forstair
waveform.

Pulse On: The on period of each pulse for pulse stair
waveform.

Stop Delay: An additional delay period at the end of
the sweep.

Pulse Off: The time period between pulses for the
pulse stair waveform.

1.

From the main menu, Press <Alt>-R.

2.

To run only the stress cycle without making C-V

measurements, select BTS Cycle. To run the entire

stress-measurement sequence, select BTS Sequence.

3.

With the probes up, select Enabie Zero to null any
system offsets.

4.

Place the probes down on the test dots, then select
Start Test. During the test, pertinent test parameters
will be displayed on the screen, and you can halt the
test by pressing any key.

5.

When the test is complete, return to the main menu.

Step 5: Analyze BTS Data

1. From the main menu, press <Alt>-A, then select
BTS.

2. Select Dispiay, Print, or Graph to display your data
as required. For exampie, press <Alt>-G to select
graphing options, then select the appropriate option.

4

Enter the bias voltage parameters necessary to bias
the device into accumulation and inversion during
the sweep. Briefly, bias voltage parameters are de­fined as follows:

First Bias V: The first DC bias voltage step value.
Bias Step V: The incremental change in the bias volt-

age waveform.

Last Bias V: The last DC bias voltage step value.
Default Bias V: The DC bias voltage applied to the

device both before and after a sweep.

5

If you have a light connected to your system, pro­gram the desired light on time. (After the inversion
voltage has been applied, and the light has been

turned off, this time period is used to allow capaci­tance to settle out to GIN)

6

Enter the cable calibration filename where indicated

(see

paragraph 2.5 for cable calibration details).

7

After you have entered all your parameters, select
Save, then enter the desired filename at the prompt.

2-19

SECTION 2

Getting Started

8. Select OK to accept parameters and rehn’n to the
main menu.

Step 2: Setup C-t Measurement Parameters

1.

From the main menu, press <AIt>-S, and select C-t
setup to display the C-t parameters menu.
Select the various measurement parameters such as

2.
range, frequency, model, and rate, as required. Use
the up/down and left/right arrow keys to move
around the parameter screen.
Enter the number of samples to take for the C-t meas-

3.
urement.

4.

Choose the various time/delay parameters. Briefly,

time parameter are defined as follows:

Start Delay: An additional delay before the test bias
is applied.

Sample Time: The time period between individual
samples in the C-t measurement.

Stop Delay: An additional delay after the last sample
before the end of the C-t measurement cycle.

5.

Enter the bias voltage parameters necessary to bias
the device as required both before and during the
sweep. Briefly, bias voltage parameters are defined
as follows:

Default Bias V: The DC bias voltage applied to the
device both before and after the C-t measurement.

Test Bias V: The DC bias voltage applied to the de­vice during the C-t measurement.

6.

Enter the cable calibration filename where indicated
(see paragraph 2.5 for cable calibration details).

7.

After you have entered all your parameters, select
Save, then enter the desired filename at the prompt.

8.

Select OK to return to the main menu.

Step 3: Program Zerbst Test Sequence Parameters

1. From the main menu, press <Alt>-S, then select
Zerbst Sequence.

2. Choose the test sequence type: multiple C-V, one
C-V, or no C-V. The multipleC-V option can be used
to test a number of dissimilar devices where a sepa-

rate C-V data set is required for each device. The one
C-V option can be used to test a number of similar
devices where only one C-V data set is required for
all the devices. The no C-V option should be used in
cases where only C-t measurements are required.
Choose the type of CMN checking: manual, auto, or

3.
none. (A light is required to use auto.)
Enter any comments in the indicated field.

4.
Program the number of devices based on your test

5.
requirements. In order to test more than one device
automatically, you must have a switching main­frame or probe sequencer that can connect to multi­ple sets of test dots automatically. See Section 6 for
information on setting up a control file for this

equipment.
Enter the C-V. C-t. and data destination filenames

6.
where indicated. These are the files set up in steps 1
and 2 above. The switch control filename should also
be specified if you are using a switching mainframe.

The data destination filename defines the storage lo-

cation for data taken during a Zerbst test.

7.

Select Save, then save the Zerbst sequence parame­ters under a convenient filename.
Select OK to return to the main menu.

8.

Step 4: Run the Zerbst Test

1.

From the main menu, Press <Alt>-R.

Select Zerbst Sequence.

2.
With the probes up, select Enable Zero to null any

3.
system offsets.

Place the probes down on the test dots, then select

4.
Start Test. During the test, pertinent test parameters

will be displayed on the screen, and you can hait the
test by pressing any key.

5. When the test is complete, return to the main menu.

Step 5: Analyze Zerbst Data

From the main menu, press <Al&A, then select C-t.
To save measurement data, press <AIt>-F, then se­lect Save C-t File and Save C-V File. Type in the de­sired filename at the prompt.
Press <Ah>-G to select the graphing option, then se­lect the Zerbst Plot option to graph Zerbst data.
Select option 7 on the graphics control menu, then

follow the prompts on the screen to determine gen-

eration velocity and lifetime.

Z-20

SECTION 3

Test Setup

3.1 INTRODUCTION 3.2 C-V MEASUREMENT PARAMETERS

This section describes setup procedures for various

Model 5958 tests:

3.2 C-V Measurement Parameters

3.3 C-t Measurement Parameters

3.4 stress Cycle Parameters

3.5 BTS Test Sequence

3.6 Zerbst Test Sequence

To access one of these setup menus, select Setup on the
main menu, then select the desired setup on the dis­played pull-down menu.

NOTE
Refer to the Model 590 Inshuction Manual for
complete details on measurement parame­ters.

C-V measurement parameters define how C-V sweeps
are performed. C-V sweeps are used for stand-alone C-V

tests, BTS test sequences, and Zerbst test sequences when
so indicated. The paragraphs below outline the C-V
measurement parameter menu and also describe the pu­pose of each parameter.

3.2.1

Figure 3-1 shows the overall format of the C-V measure­ment parameter menu. In addition to selecting and pro­gramming parameters (described below), you can per­form the following menu operations:

OK: Accepts any parameter changes and exits the

Load:

save:

Help:

Cancei: Cancels any parameter changes and exits the

C-V Measurement Parameter Menu

menu.
Loads an existing C-V measurement parameter

file.
Saves the current parameters to a designated

file.
Provides helpful information on setting pa-

rameters.

C-V parameter menu.

3-1

SECTION 3

Test Setup

- c-v Parameters

3.2.2

Range : ( ) 2pF ( ) 20pF
Frequency: (+) IOOkHz ( ) IMHZ
Model : (*) parallel ( ) series
Meas. Rate:
Filter: ( ) filter OFF
sweep Source: (*) 590 (Internal )
Waveform: (*) stair

Start Delay:
Step Time/Pulse On:
Stop Delay/Pulse Off:

Bias Voltage Parameters:

First Bias V:
Bias Step V:
Last Bias V: -5

Default Bias V: 0
Light On-Time: 10
Cable Calibration Filename:CABCALSB .CAL

< OK >

( ) llsec (*) IOlsec ( ) 18/s.% ( ) 75/set

( 1 pulse stair LIMITS

.OOl sec.

1

.OOl

(5mV resolution)

5

.05

< Load 1 < Save >

C-V Measurement Parameters

( ) 200pF

(t) filter ON

( ) 230-l (External )

sec. .OOl
sec.

V. -20 - + 20 v.
V. .005 - 20 v.
V. -20 - + 20 v.
V. -20 - + 20 v.
sec. 0 - 100 sec.

< Help >

($1 2nF

.OOl - 65 sec.

- 65 sec.

.OOl

- 65 sec.

8 chars. max

<

Cancel

Table 3-1. Reading Rates

>

Range: Selects 2pF (IOOkHz only), 20pF, 200pF, or 2nF
measurement range. For best accuracy, choose the lowest
range possible without overranging the Model 590.

Frequency: Selects IOOkHz or 1MHz test frequency.
Note that the Model 590 must be equipped with 1OOkHz
and/or IMHz modules in order to use the corresponding
frequencies.

Model: Selects parallel or series measurement model.
The Model 590 always measures the device using the par­allel model, and series model capacitance and resistance
are computed from the measured data. See paragraph 4.7
for details on parallel/series model.

Meas. Rate: Selects measurement rates of 1, 10, 18, or 75

readings per second. Note that the slower rates yield the
best accuracy, resolution, and noise performance.
Table 3-l summarizes how the selected reading rate af-

fects resolution and number of integrations averaged

(the higher the number of readings averaged, the better
the noise performance).

Measurement Reading

Rate Resolution Averaged

1 /set

lO/sec

Xi/%%

75/set 3-l/2 digits 1

The maximum effective reading rate is about

7/set when the optional Model 230-l Voltage
Source is used.

Filter: Allows you to turn the Model 590 filter on or off.
Since using the filter can slow down the effective meas­urement rate, the filter should be left off unless reading
noise is determined to be a problem. Inaccurate capaci-

tance and conductance readings may result if the filter is
used when measuring devices with rapidly changing
bias waveforms.

4-l/2 digits
4-l /2 digits
4-l /2 digits

NOTE

Integrations

4
2
1

3-2

SECTION 3

Sweep Source: If you have no optional Model 230-I Volt­age Source connected to your system, select 590 (Internal)
sweep source. To use the optional Model 230-l Voltage
Source, select 230-l (External). In general, bias voltage
values are limited to kZOV without the optional voltage
source and +lOOV with the optional voltage source.

3.2.3

Figure 3-2 and Figure 3-3 show the basic waveform defi­nitions for the waveform parameters described below.

Waveform: Selects stair or pulse stair waveform, as de­fined in Figure 3-2 and Figure 3.3.

Waveform Parameters

NOTE

All programmed time periods should be mul-

tiplied by a factor of 1.024 to obtain the actual
time periods.

Start Delay: The time period on the first bias step from
the start of the sweep until the first step time. The allow­able range is from O.OOlsec to 65%~.

Step Time/Pulse On: For the stair waveform, the step
time is the time period after transition to a new bias step
before the Model 590 begins a measurement. For the
pulse stair waveform, the pulse on time is the length of
the bias pulse. The allowable range is fmm O.OOlsec to
65s~. NOTE: When using the optional Model 230-1, the
actual minimum step time with 0.001s~ programmed is
IlOIIlSK.

Stop Delay/Pulse Off: For the stair waveform, the stop
delay is the time period after the last measurement in the
sweep before the Model 590 returns to the default bias
voltage. For the pulse stair waveform, the pulse off time
is the off time duration for each pulse. The range for this
parameter is from O.OOlsec to 65s~.

3-3

SECTION 3
Test Setup

Pulse Stair Wavefoim

Default Bias V: The bias voltage setting after the sweep

and between pulses for the pulse stair waveform. The

range is from -20V to +2OV without ihe optional Model

230-l Voltage Source, or fmm -lOOV to +lOOV with the

optional Model 230-l Voltage Source.

3.2.5 Miscellaneous Parameters

Light On-Time: If you have a light connected to your sys­tem in order to attain equilibrium more rapidly, this pa­rameter controls the length of time the light stays on

when determining CUMIN automatically. The range for the

light control parameter is from Osec to 100sec. See para­graph 2.4.4 for information on connecting a light to your
system.

Cable Calibration Filename: This parameter defines the
name of the file that holds the cable correction paramr
ters for basic C-V tests (see paragraph 2.5 for details on
performing cable correction). The cable calibration con-

i

stants stored in this file are used only for basic C-V meas­urements. Cable correction filenames for test sequences
are defined in the switch control file (see Section 6).

3.2.4 Bias Voltage Parameters

NOTE
All bias voltage parameters have a resolution of 5mV (in­ternal bias source) or 1OmV (external bias source). If an
optional Model 230-l Voltage Source is not being used,
the maximum range for all voltage parameters is i2OV.

First Bias V: The initial voltage setting of the bias

waveform. The range of this parameter is -20V to +2OV

without the optional Model 230-l Voltage Source, or
from-100V to +lOOV with the optionalMode 230-l Volt­age source.

Bias Step V: The incremental change in bias voltage of
each step in the bias voltage waveform. The range for this
parameter is from 5mV to 20V (IOmV to 20V with the op­tional Mode1 230-l Voltage Source).

Last Bias V: The final voltage setting of the bias
waveform. The range of this parameter is -20V to +2OV
without the optional Mode1 230-l Voltage Source, or
from -lOOV to +lOOV with the optional Model 230-l Volt­age source.

3.2.6

C-V Parameter Programming
Procedure

1. From the main menu, select Selup by pressing
<Alt>-S.

2. Select C-V to display the C-V parameter menu.

3. If you are loading a set of C-V measurement parame­ters from an existing file, select Load, then select or

enter the name of the C-V parameter file.

4. Program the Model 590 measurement parameters

such as range, frequency, model, rate, and filter, and
be sure to select internal or external voltage source as

appropriate.

5. Select the waveform type as well as the desired start,

step, and stop delay times. Keep in mind ihat pro-

grammed times must be multiplied by a factor of

1.024 to obtain actual times.

6. Select the first, step, last, and default bias voltage pa­rameters as required.

7. If you are using a light with your system, program
the desired light on time.

8. Enter the filename of the cable correction file.

9. To save the selected C-V parameters, select Save,
then type in the desired filename.

10. Select OK to use the new parameters, or choose Can­cel to cancel any changes made to the previously dis­play parameters.

34

SECTION 3

Test Setup

3.2.7 Saving/Loading C-V Measurement
Parameters

Saving C-V Measurement Parameters

1. From the C-V measurement parameter menu, select
Save.

2. Type in the desired filename at the prompt, or select
an existing file.

3. C-V measurement parameters will be saved with the
appropriateextensionin thecurrent directory unless
otherwise specified.

Loading C-V Measurement Parameters

1. From the C-V measurement parameter menu, select
Load.

2. Type in the desired filename, or select one of the dis­played C-V measurement parameter files.

3. C-V parameters will be loaded, and the C-V meas­ure&nt parameters menu will be updated with the
new parameter values.

3.3 C-t MEASUREMENT PARAMETERS

C-t measurement parameters control the way a C vs. t
sweep is performed. The following paragraphs describe
the C-t measurement parameter menu and associated pa­rameters.

3.3.1 C-t Measurement Parameter Menu

Figure 3-4 shows the overall format of the C-t measure­ment parameter menu. In addition to selecting and pro­gramming parameters (described below), you can per­form the following menu operations:

OK: Exits C-t parameter menu with parameter

changes placed into effect.

Load: Loads an existing C-t menu parameter file.

StWe: Saves the current C-t measurement parameters

to a designated file.

Help: Provides helpful information on setting pa-

rameters.

Cancel: Cancels parameter changes and exits the C-t pa-

rameter menu.

- C-t Parameters p

Range:
Frequency: (+ ) 1OOkHz ( ) 1MHz
Mode 1: (*) parallel
Meas. Rate: ( ) l/see (*) lO/sec ( ) lS/sec ( ) 75/set ( ) lOOO/
Filter: ( ) filter OFF (*) filter ON
sweep Source: (*) 590 (Internal) ( ) 230-l (External)

I! Samples: 100 1 - 450
Waveform Time Parameters:

Start Delay:
Sample Time:
Stop Delay: .OOl sec.

Bias Voltage Parameters: (5mV resolution)

Default Bias V:
Test Bias V: -5 v. -20 - c 20 v.

Cable Calibration Filename:CABCAL58 .CAL

< OK > < Load >

II

( ) 2pF

( 1 20pF

.OOl sec.

1

5

< Save >

( ) 200pF (+) 2nF

( 1 series

sec.

V. -20 - + 20 v.

LIMITS

.OOl - 65 sec.
.OOl - 65 sec.
.OOl - 65 sec.

8 chars.

( Help > < Cancel >

q

ax

3-5

SECTION 3

3.3.2 C-t Measurement Parameters

Range: Selects 2pF (1OOkHz only), ZOpF, 200pF, or 2nF
measurement range. For best accuracy, choose the lowest
range possible without overranging the Model 590.

Frequency: Selects 1OOkHz or 1MHz t&frequency. Note
that the Model 590 must be equipped with 1OOkH.z and/
or IMHz modules in order to use the corresponding fre­quencies.

Model: Selects parallel or series measurement model.
Readings are always taken using parallel model and then
converted to series C and R data if series model is se­lected. See paragraph 4.7 for details on paralIel/series
model.

Meas. Rate: Selects Model 590 measurement rates of 1,
10, 18, 75, or 1000 readings per second. Note that the
slower rates yield the best accuracy, resolution, and noise
performance (see Table 3-l), and that only capacitance
data is taken at the lOOO/sec rate.

Filter: Allows you to bun the Model 590 filter on or off.
Normally the filter should be left off unless noise is deter­mined to be a problem because inaccurate readings may
result if the filter is turned on with rapid waveforms.

NOTE NOTE
All programmed time periods should be mul- All programmed time periods should be mul­tiplied by a factor of 1.024 to obtain the actual tiplied by a factor of 1.024 to obtain the actual
time ueriods. See the Model 590 Instruction time ueriods. See the Model 590 Instruction
Man& for details

Start Delay: The time period the default bias is applied at
the start of the sweep. The allowable range is from

O.OOlsec to 65sec.

Sample Time: The sample time is the time interval be-

tween individual samples. The allowable range is from
O.OOlsec to 65sec. Note that the total reading interval per
step (tr) is the sum of the step time (tsM& and the recip-

rocal of the reading rate (R): tr = tsaMPu + 1 /R

Stop Delay: The stop delay is the time period after the

last measurement before the Model 590 returns to the de-

fault bias voltage. The range for this parameter is from
O.OOlsec to 65sec.

3.3.4 Bias Voltage Parameters

NOTE
All bias voltage parameters have a resolution
of 5mV (internal bias source) or 1OmV (exter­nal bias source). If an optional Model 230-l
Voltage Source is not being used, the maxi­mum range for all voltage parameters is tiOV.

Sweep Source: Select230-1 (External) sweep source only
if your system is equipped with the optional Model 230-l
Voltage Source; otherwise, you should select 590 (Inter­nal). Bias voltages are limited to tiOV without the op­tional voltage source and +lOOV with the optional volt­age source.

# Samples: Sets the number of samples for the C-t meas­urement. Limits are from 1 to 450 samples for all reading
rates except lOOO/sec, which has a 1,350 sample limita­tion.

3.3.3

Figure 3-5 shows the basic waveform definitions for the
waveform time parameters described below.

3-6

Waveform Time Parameters

Default Bias V: The bias voltage value before and after a
C vs. t sweep. The range of this parameter is -20V to t20V
without the optional Model 230-l Voltage Source, or

from -lOOV to +lOOV with the optional Model 230-l Volt-

age Source.

Test Bias V: The bias voltage setting during the C vs. t
sweep. The range for this parameter is from -20V to +2OV
without the optional Model 230-l Voltage Source, or

from-100V to +lOOV with the optionalMode 230-l Voit­age Source.

3.3.5

Cable Calibration Filename: Enter the cable correction
filename where indicated (see paragraph 2.5 for cable
correction details). The cable correction filename entered
in this menu is used only for basic C-t tests. Cable correc-

Cable Correction Filename

SECTION 3

Test Setup

Definitions:

t START = start Delay

t STOP = stop Delay

t SAMPLE = Sample Time (Programmed)

t , = Reading Interval = ~SAMPLE +1/R

(R = Reading Rate)

Time Computation:

t I = fST/iRT + (1SAMPLE + lifl) s

Where: S = Sample U

1, = Time at Sample #

.,

I I
I I
I I
I I

I I

I I

Figure 3-5.

ou---

Default

Bias U

t

S,Wt

sweep

c-t

Waveform

B. Bias Voltage

P

3-7

SECTZON 3
Test Setup

3.3.6 C-t Parameter Programming
Procedure

1.

From the main menu, select Setup by pressing

<Alt>-S.

2.

Select C-t to display the C-t parameter menu.

3.

Program the Model 590 measurement parameters
such as range, frequency, model, rate, and filter. Also
be sure to select internal or external sweep source as
appropriate.

4.

Program the number of samples to be taken during

the c-t measurement.

5.

Select the desired start, step, and stop delay times.

Keep in mind that programmed times must be multi­plied by a factor of 1.024 to obtain actual times.

6.

Select the first and test bias voltage parameters as re­quired.

7.

Enter the filename of the cable correction file.

8.

To save the programmed C-t parameters, select
Save, then type in the desired filename.

9.

Select OK to use the new parameters, or choose Can­cel to cancel any parameter changes made.

3.3.7 Saving/Loading C-t Measurement
Parameters

Saving C-t Measurement Parameters

1. From the C-t measurement parameter menu, select
S?We.

2. Type in or select the desired filename at the prompt.

3. C-t measurement parameters will be saved with the
appropriate extension in the current directory unless
otherwise specified.

Loading C-t Measurement Parameters

The stress cycle menu and corresponding parameters are
discussed below.

3.4.1

Figure 3-6 shows the format of the stress cycle parameter
menu. Note that you can perform the following menu op­erations in addition to programming parameters:

OK:

Load:

save:

Help: Provides helpful information on setting stress

Cancel: Cancels stress cycle parameter changes and ex-

3.4.2

Stress cycle parameters are summarized below. See para­graph 3.4.5 below for a description of the complete stress
CyClt-.

Bias Source: Select 230-l (External) only if you are using
an optional Model 230-l Voltage Source, otherwise

choose 590 (Internal) for the bias source. Voltage parame-

ters are limited to +.2OV without the optional voltage

source or k1OOV with the optional voltage source.

Stress Cycle Parameter Menu

Accepts stress cycle parameter changes and ex­its the menu.

Loads an existing stress cycle menu parameter
file.

Saves the current stress cycle parameters to a
designated file.

cycle parameters.

its the stress cycle parameter menu.

Stress Cycle Parameters

1. From the C-t measurement parameter menu, select
Load.

2. Type in the desired filename, or select one of the dis­played C-t measurement parameter files.

3. C-t parameters will be loaded, and the C-t measure­ment parameters menu will be updated with the
new parameter values.

3.4 STRESS CYCLE PARAMETERS

Stress cycle parameters control temperature, voltage,
and time parameters associated with the BTS stress cycle.

3-8

+Stress V: Sets the voltage value applied to the device
during the positive stress cycle. Parameter limits are 0 to
+2OV (without the Model 230-l) or 0 to +lOOV (with the
Model 230-l).

-Stress V: Programs the bias voltage value applied to the
device during the negative stress cycle. Limits for this pa­rameter are from 0 to -20V without the optional Model

230-I Voltage Source, or from 0 to -lOOV with the op-

tional Model 230-l Voltage Source.

BTS Cycle Parameters

SECTION 3

Test Setup

Bias Source: c* 1 590 (Internal )

+ stress v: 10 v. o- t2ov.

- stress v: -10 v. o- -20v.
Stress OFF V: 0 v.
Stress Temp:
Stress OFF Temp: 30 ‘C. 0 - +300 c.
Temp. Tolerance: 1 ‘C. 0.1 - 9.9 c.
Stress Time:

I

Figure 3-6.

Stress OFF V: Programs the bias voltage applied to the
device during the off period of the stress cycle. Parameter

limits are -20V to +2OV with the optional Model 230-l
Voltage Source, or -lOOV to +lOOV with the optional
Model 230-l Voltage Source.

Stress Temp: Programs the hot chuck temperature dur­ing the stress on period of the stress cycle. Limits for this

parameter are from 0°C to t300’C.

Stress OFF Temp: Sets the hot chuck temperature during

the stress off period of the stress cycle. Parameter limits
are from 0°C to +300°C.

Temp. Tolerance: This parameter programs the at tem­perature tolerance of the temperature cycle. The at tem­perature tolerance is the deviation from the programmed
stress temperature at which timing for the stress on inter­val will begin. For example, if the stress on temperature is
3OO”C, and the at temperature tolerance is 2”C, the stress
on interval will begin at a temperature of 298’C. The pro­grammable range is from O.lOC to 9.9”C tolerance.

BTS Cycle Parameters Menu

200 ‘C.

600

sec.

( ) 230-l (External)

LIMITS

-2o- +2ov.
0 - +300 c.

1 - 10000 sec.

3.4.3 Programming Stress Cycle
Parameters

1. From the main menu, press <Alt>-S, then select
stress Cycle.

2.

Select internal or external sweep source as required.

3. Set the three stress voltazes (+Stress V, -Stress V,
and Stress OFF V) as de&d.

4. Program the hot chuck temperature parameters
(Stress Temp, Stress OFF Temp, and Temp Toier­ante) to required values.

5. Set the Stress Time as needed.

6. Select Save, then type in or select the desired file­name to save newly programmed stress cycle pa­rameters.

7. Select OK to accept new parameters and return to the
main menu.

3.4.4

Saving/Loading Stress Cycle

Parameters

Saving Stress Cycle Parameters

Stress Time: Sets the time duration for the stress on pe­riod of the stress cycle, which begins when the at tem­perature toierance setting has been satisfied. The stress
time parameter range is from lsec to 10000sec.

1. From the stress cycle parameter menu, select Save

2. Type in the desired f&name at the prompt.

3. Stress cycle parameters will be saved with the appro­priate extension in the current directory unless oth­erwise specified.

3-9

SECTION 3

Loading Stress Cycle Parameters

1. From the stress cycle parameter menu, select Load.

2.

Type in the desired filename, or select one of the dis­played stress cycle parameter filenames.

3.

Stress cycle parameters will be loaded, and the stress
cycle parameters menu will be updated with the new

parameter values.

3.4.5

Stress Cycle Description

The basic purpose of the stress cycle is to apply both a
bias voltage and temperature stress to the DUT. The basic
sequence for the strews cycle is summarized below. A
flowchart for the stress cycle is shown in Figure 3-7.

1. When the stress cycle is first started, the bias voltage
and temperature will be set to Stress OFF V and
Stress OFF Temp. respectively.

2. The device is biased with the +Stress V or -Stress V
value, depending on whether the stress cycle is posi-

tive or negative.

3.

The hot chuck temperature is ramped up to the value
determined by the Stress Temp. parameter.

4.

Once the hot chuck temperature reaches the toler­ance value determined by the Temp. Tolerance pa­rameter, stress cycle timing begins.

5.

The DUT remains at stress temperature and bias
voltage for the time interval determined by the
Stress Time parameter.

6.

Once the required stress time has elapsed, the hot
chuck is ramped down to a temperature determined
by the Stress OFF Temp. parameter, and the bias
voltage is set to the value determined by the Stress
OFF v parameter.

3-10

‘igure3-7.

Stress Cycle FIowchart

SECTION 3

Test Setup

3.5 BTS TEST SEQUENCE

BTS test sequence parameters define the test sequence
type, number of devices to test, as well as the various con­trol and parameter files associated with the BTS test.

3.5.1 BTS Test Sequence Menu

Figure 3-8 shows the BTS test sequence menu. The vari­ous parameters defined in this menu are used when M­ning a BTS test sequence, as described in paragraph 4.5.

Use the selections at the bottom of the screen to perform

the following:

OK:

Load:

Save:

Help: Provides useful help information on program-

Cancel: Cancels mrameter chases and exits the BTS

Accepts entered BTS test sequence parameters
and exits the test sequence menu.

Loads an existing BTS test sequence file.
Saves the present BTS test sequence parameters

in a user-defined file

ming BTS test sequence parameters.

test sequence menu.

3.5.2

BTS Test Sequence Setup

Parameters

Test

Sequence Type: Selects sequential, parallel, or no
stress, as required. See paragraph 3.5.5 below for a m”re
detailed discussion of test sequence types.

Stress Cycle Type: Sets + then -, - then +, + only, or ­only. With+ then-or- then+, bothpositiveandnegative
voltages (+Stress V and -Stress V) will be applied to the
device in sequence during stress (+Stress V then Stress
V, or -Stress V then +Stress V). With + only and - only
positive and negative voltages respectively will be ap­plied to the device during stress. Flowcharts discussed in
paragraph 3.5.5 show how the various stress cycles work
with test sequences.

Type

of

CMIN Checking: If you have multipie devices,
you may or may not want to determine hue Cxw for
each device. Choosing manual indicates the program will

stop at the end of each sweep and py”mpt you for certain
information (see paragraph 4.2.4). The auto selection,
which appears only if you have an optional Model 230-l
voltage source, is completely automatic, and it requires
that you have a light connected to the system (paragraph

2.4.4). Choosing none results in automatic program “p-

er&ion, but Cw~is not determined. (CUN can also be en­tered under analysis, as discussed in paragraph 5.6.3 in
Section 5.)

_

Fisure 3-8.

BTS Test Sequence

Test Sequence Type: ( ) sequential
Stress Cycle Type:
Type

of Cmin Checking: (*I manual ( ) auto

(Enter on next: line)

(+ 1 cthen- ( 1 -then+

(*) parallel

( ) no stress

( 1 none

64

chars.

This is a sample BTS test sequence file distributed with 5958.

Number of Devices: i

C-V Parameter Filename: SAMPLE

Stress Cycle Filename: SAMPLE

Switch Control Filename: ----

Data Destination Filename: SAMP-

BTS Test SequenceSetupMenu

3-11

SECTION 3
Test Setup

Comments: Allows you to type in one line of up to 64
characters of comments for future reference.

Number of Devices: Sets the number of devices to test
(l-99). In order to test more than one device, you must use
a switching mainframe or probe sequencer and define a
switch control file (see Section 6).

C-V Parameter Filename: Defines the filename that con­tains the C-V parameters for the C-V portion of the BTS
test sequence. See paragraph 3.2 for information on pro­gramming these parameters.

6.

Select the number of devices to test (only one device
can be tested if no switching or sequencing provi­sions are included in your system).

7.

Enter your C-V parameter filename, as determined
in step 1.

8.

Typein thestresscycleparameterfilenamechosenin
step 2.

9.

If you are using a switch (or sequencer), enter the
switch control filename (Section 6 describes setting
up a switch control file).
Type in the data destination filename to define

10.
where data taken during the BTS test sequence will
be stored.

11.

Select Save, then type in the desired filename to save

the defined test sequence.

Stress Cycle Filename: Defines the filename of the stress
cycle parameters. Paragraph 3.4 describes how to pro­gram stress cycle parameters and have them in an appro­priate file.

Switch Control Filename: Defines the switch control
filename, which is required when using switching with
the BTS system. See Section 6 for information on setting
up the switch control file.

Data Destination Filename: Defines the file in which
BTS test sequence data will be stored at run time.

NOTE
The maximum number of characters for each
filename is indicated on the screen. Also, you
should not type in filename extensions be­cause the extensions are automatically added
by the program.

3.5.3

1.

2.

3.

4.

5.

Setting Up a BTS Test Sequence

Setup your C-V measurement parameters, as dis-

cussed in paragraph 3.2. Be sure to save the parame­ters using a convenient filename.
Program the stress cycle parameters, which are de-

scribed in paragraph 3.4. Again, save the stress cycle

parameters using the Save option on the menu.

From the main menu, press <Ait>-S, then select BTS
Sequence.
Select your test sequence type, stress cycle type, and
Cm checking type.

Enter any comments for reference on the indicated

line.

3.5.4 Saving/Loading BTS Test
Sequence Setups

Saving BTS Test Sequence Seh~ps

1. From the BTS test sequence menu, select Save.

2. Type in or select the desired filename at the prompt.

3. The BTS test sequence setup will be saved with the
appropriateextensionin thecurrent directory unless

otherwise specified.

Loading BTS Test Sequence Setups

1. From the BTS test sequence setup menu, select Load.

2. Type in the desired filename, or select one of the dis­played BTS test sequence setup files.

3. The BTS test sequence setup will be loaded, and the

BTS test sequence setup menu will be updated ac­cordingly.

3.5.5 BTS Test Sequence Description

NOTE
Test sequencing of multiple devices requires
that you define a control file or use one of the
default switch control files. See Section 6 and
Appendix J for details.

Sequential Test

With a sequential test, the entire BTS sequence is per­formed on each device while it is connected to the system.
The basic steps for the sequential test using a + then ­stress cycle are summarized below. Figure 3-9 through
Figure 3-12 show flowcharts for the sequential test se-

3-12

quence using the four available stress cycles (+ then -, ­then f, f only, and -only).

1. If a switch or automatic probe sequencer is being
used, a switch control string (from the switch control
file) is sent to the switching mainframe or sequencer
to select the device being tested.(With the switch, re­lay contacts are closed to select the DUT, while a po-

sitioning device selects a specific test dot with a

probe sequencer.)

2. An initial, pre-stress C-V curve measurement is per­formed, and the resulting data is stored in a disk file.

3. The positive BTS stress cycle is applied to the device.
This stress cycle includes the positive stress voltage
and the programmed stress temperature.

4. A second C-V curve measurement is made, and the
data is stored in a disk file.

5. The negative BTS stress cycle is applied to the device.
The negative stress cycle includes the programmed
negative stress voltage and the programmed tem­perature.

6. A third C-V measurement is made, and the results
are stored in a disk file.

7. If a switch is being used, a switch control string is
sent to the switching mainframe to open the contacts
to the device being tested.

8. Steps 1 through 7 are repeated for all devices to be
tested.

9. The bias voltage is turned off to alIow for safe device
removal.

s I

SECTlON 3

Test

Setup

‘igure 3-9

BTS Sequentid Test Flowchart
i+ Then -Stress Cycle)

3-13

SECTION 3
Test Setup

Measure

Pre-St,***

52

c-v

‘igure3-10.

3-14

All

Devices No

Tested?

Yes

G

BTS Sequential Test Flowchart
C- Then +Stress Cyclei

!igure3-11.

I

End

I

d3

BTS Sequential Test Flowchart
c+ Only stress Cyclei

+.pre3-12.

End

22

BTS Sequentid Test Flowchart
C-Only stress CycleJ

SECTION 3

Test Setup

Parallel Test

The parallel sequence test has the advantage of speeding

up BTS measurement of a number of devices by perform­ing time-consuming stress operations in parallel. Basi­cally, all devices are stressed in parallel and tested at each
stage (pre-stress, positive stress, negative stress) before
moving on to the next stage. Note that switching is re­quired for this test because all devices must be connected
in parallel during the stress cycle, a requirement that can­not be met by an automatic probe sequencer.

The steps below outline the overall parallel test sequence
for the + then-stress cycle, which is shown in the flow­chart of Figure 3-14. Figure 3-14 through Figure 3-16
show flowcharts for the parallel test with the remaining
stress cycle types.

1. A switch control string is sent to the switching main­frame to close the contacts to connect the device to be
tested.

2. A pre-stress C-V curve measurement is made, and
the data is placed in a disk file.

3. A switch control string is sent to the switching main­frame to open the contacts connecting the current
device.

4. Steps 1 through 3 are repeated for all devices to be
tested.

5. A switch control string is sent to the switching main­frame to connect all devices in parallel.

6. The positive BTS stress cycle is applied to all devices
simultaneously.

7. A switch control string is sent to the switching main­frame to disconnect parallel devices.

8. A switch control string is sent to the switching main­frame to close the contacts toconnect the device to be

tested.

9.

A second C-V curve measurement is made, and the

resulting data is stored in a data file.

10. A switch control string is sent to the switching main­frame to open the contacts connecting the current

device.

11. Steps 8 through 10 are repeated for all devices to be
tested.

12. A switch control string is sent to the switching main­frame to connect all devices in parallel.

13. The negative BTS stress cycle is applied to all devices

simultaneously.

14. A control string is sent to the switching mainframe to
disconnect all parallel devices.

15. A switch control string is sent to the switching main­frame to close the contacts to connect the device to be
tested.

16. A third C-V curve measurement is made, and the re­sulting data is stored in a disk file.

3-15

SECTION 3
Test Setup

17. A switch control string is sent to the switching main­frame to open the contacts connecting the current
device.

18. Steps 15 through 17 are repeated for all devices to be
tested.

19. The bias voltage is turned off to allow for safe device
removal.

No Stress Test

The no stress test option performs only a basic C-V curve
measurement without stress. This option can be used to
verify for proper C-V measurement parameters and de­vice connections, or for basic multiple-device C-V meas­urements.Aswitchingmainframeorautomaticprobese­quencer can be controlled to test a number of d&vices
automatically.

The basic steps included in the no stress test are summa­rized below. Figure 3-17 shows a flow chart of the BTS no
stress test sequence.

1. A control string is sent to the switching mainframe
or probe sequencer to select the device to be tested.

2. A C-V curve measurement is made, and the resulting
data is stored in a disk file.

3. If switching is being used, a switch control string is
sent to the switching mainframe to open contacts to
the device being tested.

4. Steps 1 through 3 are repeated for each device being
tested.

5. The bias voltage is turned off to allow for safe device
removal.

‘igure3-13. BTS Parallel Ted Sequence Flowchart

i+Thci~ -Stress Cyclei

3-16

SECTION 3

Test Setup

Figure 3-14.

BTS Parallel Test Sequence Flowchart
i-Then +Stress Cycle)

Figure 3-15.

BTS Parallel Test Sequence Flowchart
i+Onlv stress Cuclei

3-17

SECTION 3
T&-t Setup

‘igure 3-16.

3-18

BTS Parallel Test Sequence Flowchart
(-Only Stress

Cycle-J

!igure 3-17.

BTS No Stress Sequence Flowchart

SECTION 3

Test setup

3.6 ZERBST TEST SEQUENCE

Zerbst test sequence parameters define the test sequence

type, number of devices to test, as well as the various con­troland measurement parameter files associated with the
test.

3.6.1 Zerbst Test Sequence Setup Menu

Figure 3-18 shows the Zerbst test sequence setup menu.
Parameters defined in this menu are used when running
a Zerbst test sequence, which is covered in paragraph4.6.
Use the selections at the bottom of the screen to perform
the following:

OK: Accepts entered Zerbst test sequence parame-

ters and returns to the main menu.

Load: Loads an existing Zerbst test sequence sefup

file.

save:

Help: I’rovides useful help information on program-

Saves the presentzerbst test sequence setup in a
user-defined file

ming Zerbst

test

sequence setup parameters.

Comments: Use this feature to type in one line of up to 64

characters as comments for future reference. Comment

text is entered on the next line.

Number of Devices: Selects the
(l-99). In order to test more than one device, you must use
a switching mainframe or probe sequencer and define a

switch control file (see Section 6).

C-V Parameter Filename: Defines the filename that con­tains the C-V measurement parameters. See paragraph

3.2 for information on programming these parameters.

C-t Parameter Filename: Defines the filename with C-t
measurements parameters, as covered in paragraph 3.3.

Switch Control Filename: Defines the switch control
filename, which is required when using switching or se­quencing with the Zerbst system. See Section 6 for infor­mation on setting up the switch control file.

number

of devices to test

Cancel: Exits the Zerbst test sequence menu.

3.6.2 Zerbst Test Sequence Setup
Parameters

Test Sequence Type: Select multiple C-V, one C-V, or no

C-V, as required. See paragraph 3.6.5 below for a more
detailed discussion of test sequence types.

Type of CMIN Checking: Selects whether or not Cm will
be determined (see paragraph 3.52).

Data Destination Filename: Defies the files in which
Zerbst test data will be stored.

NOTE

The maximum number of characters for each

filename is indicated by the length of the field

displayed on the screen. Also, you should not

type in filename extensions because the exten-

sions are automatically defined by the pro-

gr-.

3-19

SECTION 3

Zerbst Test Sequence

Test Sequence Type:
Type of Cmin Checking:

Comments:

This

Figure 3-18. Zerbst Test Sequence Menu

3.6.3

1. Setup your C-V measurement parameters, as dis-

2. Program the C-t measurement parameters, which

3. From the main menu, press <A&>-S, then select

4. Select your test sequence type and type of CNW

5. Enter any comments for reference on the indicated

6. Select the number of devices to test (only one device

7. Enter your C-V parameter filename, as determined

8. Type in the C-t measurement parameter filename

9. If you are using a switch or sequencer, enter the

10. Type in the data destination filename to define

Setting Up a Zerbst Test Sequence

cussed in paragraph 3.2. Be sure to save the parame-

ters using a convenient filename.

are described in paragraph 3.3. Again, save the C-t
measurement parameters using the Save option on
the menu.

Zerbst Sequence.

checking.
line.

can be tested if no switching or sequencing provi­sions are included in your system).

in step 1.

chosen in step 2.

switch control filename (Section 6 describes setting
up a switch control file).

where data taken during the Zerbst test sequence
will be stored.

is a

C-V Parameter Filename: SAMPLE
C-t Parameter Filename: SAMPLE CTP

Switch Control Filename: ---- :swc 8 chars.

Data Destination Filename: SAMP-

(Enter on next line)

sample

Number

Zerbst test

of Devices: 1

(*I multiple C-V

(*) manual ( ) auto ( ) none

sequence file distributed with 5958

( ) one C-V ( ) no C-V

LIMITS

64 chars.

99 max.

CVP 8 chars.

8 chars.

< Cancel >

11. Select Save, then type in or select the desired fiie­name to save the defined test sequence.

3.6.4

Saving/Loading Zerbst Test
Sequence Setups

Saving Zerbst Test Sequence Setups

I. From the Zerbst test sequence setup menu, select

SFi”C

2. Type in or select the desired filename at the prompt.

3. The Zerbst t&sequence setup will be saved with the
appropriate extension in the current directory unless
otherwise specified.

Loading Zerbst Test Sequence Setups

1. From the Zerbst test sequence setup menu, select
Load.

2. Type in the desired filename, or select one of the dis­played Zerbst test sequence setup files.

3. The Zerbst test sequence setup file wilI be loaded,

and the Zerbst test sequence setup menu will be up-

dated accordingly.

3-20

SECTION 3

Test Setup

3.6.5 Zerbst Test Sequence Types

NOTE.

Test sequencing of multiple devices requires

that you define a control file or use one of the
default switch control files. See Section 6 and
Appendix J for information.

Multiple C-V Test

The multiple C-V test is intended for use with dissimilar

devices where both C-V and C-t tests are required for all
devices. The basic steps included in the multiple C-V test
are summarized below. Figure 3-19 shows a flowchart of
the test sequence.

1.

A switch control string horn the switch control file is
sent to the switching mainframe or automatic probe
sequencer to select the device being tested.
A C-V curve measurement is made, and the C-V data

2.
is stored on disk.

3.

A C-t measurement is made, and the C-t data is
stored on disk.

4.

If a switch is used, a switch control string is sent to
the switching mainframe to open the contacts to the
current device.

5.

Steps 1 through 4 are repeated for all devices to be
tested.

6.

The bias voltage is removed to allow for safe device

rf?lXlOVal.

One C-V Test

The one C-V test can be used to test a group of similar de­vices. With this type of test, only one C-V measurement
on a single device is performed, while C-t measurements
are performed on all devices being tested. In order for
this test to be valid, the first device tested in the sequence
must be representative of all devices.

The steps for the test are outline below, and Figure 3-20
shows a flowchart of the test sequence.

1,

A control string from the switch control file is sent to
the switching mainframe or automatic probe se­quencer to close the contacts for the device being

tested.
For the first device tested only, a C-V curve measure-

2,

ment is made, and the C-V data is stored on disk.
A C-t measurement is made, and the C-t data is

3,

stored on disk.
If a switch is used, a switch control string is sent to

4,

the switching mainframe to open the contacts to the
current device.
Steps 1 through 4 are repeated for ail devices to be

5

tested.

6

The bias voltage is removed to allow for safe device
remOVal.

No C-V Test

As the name implies, the no C-V test type performs only
C-t measurements. This test sequence is intended for per­forming automatic sequencing of multiple C-t tests. The
basic steps in the procedure are outlined below, and
Figure 3-21 shows a flowchart of the test sequence.

1.

A control string from the switch control file is sent to

the switching mainframe or automatic probe se­quencer to select the device being tested.
A C-t measurement is made, and the C-t data is

2.
stored on disk.

If a switch is used, a switch control string is sent to

3.

the switching mainframe to open the contacts to the
current device.

4.

Steps 1 through 3 are repeated for all devices to be

tested.

5.

The bias voltage is removed to allow for safe device

removal.

3.21

SECTION 3
Test Setup

Figure 3-19. Multiple C-V Sequence Flowchart

3-22

‘igure 3-20.

One C-V Test Sequence Flowchart

SECTION 3

Test Setup

-i,qure 3-21,

Remove

Bias

I I

No C-V Test Sequence Flowchart

3-23

SECTION 4

Measurement

4.1 INTRODUCTION

This section includes detailed information on performing
various Model 5958 measurement procedures and is or­ganized as follows:

4.2 C-V Measurements: Details test connections, C-V
measurement procedures, and discusses selecting

optimum parameters.

4.3 C-t Measurements: Covers test connections, typical
C-t measurement procedures, and discusses opti-

mum time selection.

4.4

BTS Stress Cycle: Briefly discusses hot chuck con­nections and outlines the basic procedure for per­forming a BTS stress cycle.

4.5 BTS Test Sequence Measurements: Covers connec-

tions to scanner and matrix card, basic BTS test se­quence measurement procedure, and choosing the
best test sequence.

4.6 Zerbst Test Sequence Measurements: Details con-

nections to a switch card and
measurement procedure.

4.7 Measurement Considerations: Discusses a number

of important considerations to keep in mind when
performing measurements.

Zerbst test

sequence

4.2 C-V MEASUREMENTS

Basic C-V measurements involve setting up your C-V
measurement parameters, connecting the Model 590 to
the DUT, and performing the test procedure outlined be­1OW.

NOTE

The basic C-V test procedure cannot use

switching or sequencing to test multiple
DUTs. To perform C-V measurements on
multiple DUTs, setup a BTS test sequence and
select the no stress option. See paragraph 4.5
for details.

4.2.1 C-V Measurement Connections

Figure 4-l shows typical test connections for C-V meas­urements. Since no switching or sequencing is used, con­nections are straightforward. When making connections,
keep the following points in mind:

l

Keep cable lengths as short as possible (five meters

maximum). -

. Use only 5Ofi (RG-58) cables such as the Model 7051.
. Match all instrument. cable. and adauter imoedances

to as close to 5OQ as possible.

. Minimize the total number of connections to avoid

losses caused by inevitable mismatch at connecting
points.

I I

4-l

SECTION 4
MeaSUiZl7Wlt

Figure 4-I.

e Shield probes as close to wafer as possible, and shield

wafer with Faraday shield.

. Perform cable correction before making measure-

ments (paragraph 2.5).

l

Connect INPUT to gate, OUTPUT to substrate to mini-

mize

noise.

Typical Test Connections for Basic C-Vand C-t Measurements

4.2.2 Selecting Optimum C-V
Measurement Parameters

when programming c-v measurement parameters,
keep the following points in mind. Refer to paragraph 4.7
for a more complete discussion of these and other consid­erations.

Choosing Optimum Start and Stop Voltages

Most C-V data is derived from the steep transition, or de­pletion region of the C-V curve (see Figure 4-Z). For that
reason, start and stop voltages should be chosen so that

the depletion region makes up about l/3 to Z/3 of the
voltage range.

The upper flat, or accumulation region of the high-fre-

quency C-V curve defies the oxide capacitance, Cox.

Since much analysis relies on the ratio C/Cox, it is impor­tant thatyouchooseastartorstopvoltage (dependingon
the sweep direction) to bias the device into strong accu­mulation at the start or end of the sweep.

The Model 5958 software will automatically recommend
the maximum high-frequency capacitance as the value

forCox,butyoucanenteryourownvalueifyouhaverea­son to believe that the device would saturate at a higher
value. See paragraph 5.6 for more information on chang­ing Con.

Selecting the Number of Data Points

The relative values of the start, stop, and step voitages de-

termine the number of data points in the sweep. When

choosing these parameters, some compromise is in order

between having too few data points in one situation, or

too many data points in another.

The complete doping profile is derived from data taken

in the depletion region of the curve by using a derivative

calculation. As the data point spacing decreases, the ver-

tical point spacing is increasingly caused by noise rather

than changes in the desired signal. Consequently, choos-

ing too many points in the sweep will result in increased

4-2

SECTION 4

MP”WYf?WW?d

Accumulation Depletion

VFB VTH

Figure 4-2.

noise rather than an increased resolution in measure­ment of the C-V waveform.

To minimize noise, choose parameters that will yield a
capacitance change of approximately ten times the per­centage error in the signal. For the Model 5958, the opti­mum step size is about 1% change in capacitance value
per step.

Sweep Direction

For high-frequency C-V sweeps, you can sweep either
from accumulation to inversion, or from inversion to ac­cumulation. Sweeping from accumulation to inversion
will allow you to achieve deep depletion--profiling
deeper into the semiconductor than you otherwise
would obtain by maintaining equilibrium. When sweep­ing from inversion to accumulation, using a brief light
pulse before the start of the sweep will yield near-equilib­rium results.

Basic High-frequency C-V Curve

Inversion

VGS

Step 1: Connect the Test Equipment

Connect the Model 590 to the test fixture or probe station

using the connections outlined in Figure 4-l.

Step 2: Setup C-V Measurement Parameters

1. From the main menu, press <Alt>-S, and select C-V
setup to display the C-V parameters menu.

2. Select the various measurement parameters such as
range, frequency, model, and rate, as required. Use
the up/down and left/right arrow keys to move
around theparameterscreen.Seeparagraph4.2.2for
a discussion on choosing optimum parameters.

3. Choose the waveform type and various time/delay
parameters. Remember to use a step time long
enough so that the device remains in equiiibriun

throughout the sweep. Also, you should be certain to

program a sufficiently long start delay time to allow

the device to reach equilibrium before the sweep be-

gins when sweeping from inversion to accunula-

tion.

4.2.3

The step-by-step procedure below, outlines the basic

procedure for making C-V measurements. For more in­formation on setting up C-V parameters, refer to para­graph3.2, Section3. Section5 coversC-Vanalysis inmore
detail.

C-V Measurement Procedure

Briefly, time parameters are defined as follows:

Start Delay: An additional delay period at the begin­ning of the first bias step.

Step Time: The time period for each bias step for stair
waveform.

Pulse On: The on period of each pulse for pulse stair
waveform.

4-3

SECTION 4
M~llN&WtWlt

Stop Delay: An additional delay period at the end of
the sweep.

Pulse Off: The time period between pulses for the

pulse stair waveform.

4. Enter the bias voltage parameters necessary to bias
the device into accumulation and inversion during
the sweep. Briefly, bias voltage parameters are de­fined as follows:

First Bias V: The first DC bias voltage step value.
Bias Step V: The incremental change in the bias volt-

age waveform.
Last Bias V: The last DC bias voltage step value.
Default Bias V: The DC bias voltage applied to the

device after a sweep, and during pulse off time.

5. If you have a light connected to your system, pro­gram the desired light on time.

6. Enter the cable calibration filename where indicated

(see paragraph 2.5 for cable calibration details).

7. After you have entered all your parameters, select
Save, then enter the desired filename at the prompt.

8. Select OK to return to the main menu.

Step 3: Perform a C-V Measurement

1. From the main menu, press <Alt>-R, then select C-V.
The window shown in Figure 4-3 will be displayed.
Note that capacitance, conductance, and voltage bias

readings are continuously updated and dispiayed.
At the bottom of the window, four selections allow
you to perform the following:

Start Sweep: Starts the C-V sweep.
Enable/Disable Zero: Toggles Model 590 zero on or

off.
Enable/Disable Light: Toggles the light on/off if

you have a light connected to the Model 230-l digital

If

0 port.

Cancel: Exits this window and returns you to the
main menu.

2. Make sure that the probes are up and that zero is
turned off (select Disable Zero).

3. Allow the reading to settle, then select Enable Zero
to null any offsets in the system.

4. Place the probes down on the test dots.

5. If you are using a light, bun the light on until the de­vice reaches equilibrium. Turn the light off before
starting the sweep.

6. Select Start Sweep to begin the sweep. After a mes­sage that instruments are being configured, the win­dow shown in Figure 4-4 will be displayed. Note

that the sweep time, start voltage, and stop voltage
are displayed during the sweep, and you can press
any key to halt the sweep.

7. After the sweep is completed, a message indicating

that data is being read from the Model 590 will be

displayed, and you will be prompted as to whether

or not you want to determine G&m.

Sweep will take 22.9

Capacitance Conductance

Figure 4-3. Run C-V Sweep Window

4-4

Run C-V Sweep p.

seconds.

CO.0063 US

step Voltage

co.500 v

stop

voltage

SECTION 4

Measurement

8. Select auto or manual on the displayed menu to de­termine CXN, then refer to paragraph4.2.4 below. Se­lect Cancel if you do not wish to determine Cm, and

Analysis Constants may require updating to correspond to
new data.

. ..Buffer filling...

Figure 4-4. C-V Sweep in Progress Window

the window shown in Figure 4-5 will be displayed.

9. Select Sweep Done to rehun to the main menu.

stop Voltage

start Voltage

Figure 4-5. C-V

Analysis Constants may require updating to correspond to

new data.

stop Voltage j

c5.000

Sweep Cycle Completed

COMPLETED sweep.

201 readings taken.

Window

-5.000

< Done >

(

4-5

SECTION 4
Measurement

Step 4: Save and Analyze C-V Data

From the main menu, press <AIt>-A, then select
c-v.

To save your C-V data, press <Alt>-F to select file op-

erations, then choose Save. Enter the desired file­name to save the data.
Return to the C-V Analysis menu, then press
<AIt>-D to display data arrays or constants. You can
also use <Alt>-I? to print arravvalues or constants on
your printer. . ’
To graph C-V data, press <Alb-G while in the C-V
ANALYSIS menu. Typical C-V graphs include C vs.
V and G vs. V.

4.2.4 Determining CMIN

CMIN is the minimum equilibrium high-frequency capaci-

tance with the device biased in strong inversion. The cor­rect value of CMIN is important for calculating average
doping, NAVG, for determining optimum C-t measure-

ment time, and for accurate Zerbst plots. You can deter-

mine Cm automatically or manually by using the appro-

priate procedure outlined below. Note that the CM~

analysis constant (Section 5) is updated with the new

Cm value determined by either of these methods.

3. If you are satisfied with the dispiayed inversion volt­age, select Apply Voltage, or choose New Voltage if
you wish to program a new voltage.

4. If you choose to program a new inversion voltage,
the window shown in Figure 4-8 will be dispiayed.
Type in the desired voltage, press <Enter>, then se-

lect Apply Voltage when finished.

NOTE
When programming the voltage, be sure to
choose a value that will bias the device in
strong inversion.

The window shown in Figure 4-9 will be displayed.

5.
Turn on the light for a period sufficiently long for the

device to reach equilibrium, then turn off the light
before proceeding. Select OK after turning off the
light; the program will then display the measured
value of &IN (Figure 4-10) and the C,w., value taken
from C-V sweep data. Select OK to accept the value,
or choose Repeat to repeat the procedure. Select
Cancel to leave CMIN unchanged. You can also use
this manual procedure without a light, but the time

to reach equilibrium will typically be much longer.

Auto Method

Manual Method

The manual method requires that you manually select an

appropriate inversion bias voltage. You can use the man-

ual procedure either with or without a light, although the

time to reach equilibrium will be much longer without a
light.

Proceed as follows:

1. At the end of each C-V sweep, the window shown in
Figure 4-6 will be displayed. To determine CUIN
manually, select Manual, or select Cancel to exit the

window without determining CM~N.

2. Note that inversion v&age window shown in
Figure 4-7 is displayed. This window displays the
current bias voltage and gives you the opportunity
to change or apply the voltage.

WARNING
Hazardous voltage may be applied to the de­vice if an optional Model 230-l Voltage
Source is being used. Use caution when
working with voltages greater than 30V.

The auto method of determining Cm is fully automatic,

with no operator intervention required.

NOTE
In order to use the auto method, you must
have a tight connected to the digital I/O port

of the optional Model 230-l Voltage Source.
Refer to paragraph 2.4.4 for details on connec­tions. Also, you must configure the software
for light operation during installation or re-

configuration.

The auto CM~ method uses the cutoff method shown in

Figure 4-11.Thedeviceisinitiallybiasedinaccunulation

with the light off, then biased in deep depletion, also with

the light off. The device is then biased in inversion with
the light on, and the capacitance is allowed to decay to
Cm with the light off. Note that the light on and light off
times are both determined by the programmed Light On-

Time parameter, which can be set using the C-V parame-

ters setup menu.

To use the auto method, simply select Auto at the Auto/

Manual prompt. CMPJ will be automatically measured
and updated.

4-6

SECTION 4

Measurement

or light control, select 'Auto'.

< Auto > < Manual 1

‘igure 4-6. Auto/Manual Selection Window

A potentially hazardous voltage could
be applied to the device if you are using a 230-l.
Please use caution when the voltage is applied.

Otherwise select

< Cancel >

COMPLETED sweep.

readings taken.

cigure4-7.

When you are ready apply the voltage selected by the

program or enter a new voltage by pressing the
appropriate selection.

Inversion Voltage: -4.999 volts

( Apply voltage > < New Voltage >

Inversion Voltage Window

< Cancel >

4-7

COMPLETED sweep.

readings taken.

Figure 4-8.

cigure 4-9.

New Inversion Voltagr Window

Turn on the light for the duration you desire.
When you are finished. press OK

Voltage Applied:

start Voltage

Voltage Applied Window

7 volts

< Cancel >

COMPLETED sweep.

readings taken.

4-8

NOT

SECTION 4

Measurement

Measured value: 1.058E-11 farads

Value from data: l.O54E-11 farads

start Voltage

+10.000 COMPLETED sweep.

Figure4-10. CMIN

< OK > < Repeat >

Display Window

< Cancel >

201 readings taken.

stop Voltage

-10.000

//

Figure 4-11.

Time

Auto C,wrrr Measurement Method

4-9

SECTION 4
Measurement

4.3 C-t MEASUREMENTS

Basic C-t measurements involve setting up your C-t
measurement parameters, connecting the Model 590 to
the DUT, and performing the test procedure outlined be­1OW.

NOTE
The basic C-t test procedure cannot use
switching or sequencing to test multiple
DUTs. To perform C-t measurements on mul-

tiple DUTs, setup a Zerbst test sequence and

select the no C-V option. See paragraph 4.6 for

details.

4.3.1

C-t Measurement Connections

Test connections used for basic C-t meawrements are the
same as those used for basic C-V measurement and are

shown in Figure 4-1. Keep the following points in mind
when making connections.

l

Keep cable lengths as short as possible (five meters
IIlUilIlU~).

l

Use only 50R (RG-58) cables such as the Model 7051.

l

Match all instrument, cable,

and

adapter impedances

to as close to 5OQ as possible.

l

Minimize the total number of connections to avoid
losses caused by inevitable mismatch at connecting
points.

l

Shield probes as close to wafer as possible, and shield
wafer with Faradav shield.

l

Cable correct the system before making measure­men& (paragraph 2.5).

l

Connect INPUT to gate, OUTPUT to substrate to mini­mize noise.

4.3.2

Choosing Optimum C-t
Measurement Parameters

Choosing Optimum Voltages

When setting up C-t measurement parameters, you can
set the default bias and test bias voltages to step from ac­cumulation to inversion, from depletion to inversion, or
frominversion tostronginversion. Accumulation, deple­tion, and inversion boundaries can be determined by
running a C-V measurement on the device, as discussed
in paragraph 4.2. Note that the flatband voltage (VFB) re-

gion separates the accumulation and depletion regions,
and the threshold voltage (Vm) separates depletion from
inversion (see Figure 4-Z).

Accumulation to Inversion

Stepping from accumulation to inversion provides the

most

active bias condition for interface traps. During ac­cumulation, the surface is accumulated, and interface
traps are fiIIed. When inversion bias is applied, the sur­face is initially depleted, and the filled interface traps
contribute to filling the inversion layer during the initial
period of the transient voltage before shielding mini­mizes the effects of interface traps.

Depletion to Inversion

Stepping from depletion to inversion minimizes inter­face trap effects, but this method does not provide initial
shielding. While the device is biased in depletion, the sur­face is depleted, and interface traps are partially filled.
When the inversion bias is applied, only a small amount
of the inversion layer charge is txusferred from interface

IZiPS.

Inversion to Strong Inversion

Stepping from inversion to strong inversion provides
bias conditions that result in the least amount of interface
trap effects. During inversion, the inversion layer is
populated, and interface traps are shielded. During
strong inversion, the inversion layer shields interface

traps from contributing to additional generation.

Choosing Optimum C-t Measurement Time

The total time period of a C-t measurement is determined
by the sample time and the number of samples in the
measurement. These two parameters should be carefully
chosen to obtain the optimum C-r measurement time. If
you choose a measurement time that is too short, only a
portion of the transient capacitance waveform will be
measured. If you program too many samples, only a few
samples will be taken during the important transient por­tion of the waveform, with the majority of the samples
being taken at the end point where the capacitance has
reached its final value.

One recommended method for

determining

optimum

C-t measurement time is to set parameters resulting in a

4-10

capacitance cutoff point of 95% of CM~. The basic proce­dure for this method is as follows:

Perform a C-V sweep on the device, as outlined in

1.
paragraph 4.2. Be sure to program start and stop

voltages that bias the device well into accumulation
and inversion during the sweep (see Figure 4-2).
Also be sure that step time is sufficiently long so that

the device remains in equilibrium throughout the

5WSp.

Determine Cm, as covered in paragraph 42.4.

2.

3.

Return to the Setup/Run main menu, then setup
your preliminary C-t measurement parameters (re­fer to paragraphs 3.3 and 4.3.3 below).
From the main menu, press <AI>-R, then select C-t
to run the C-t measurement.
After the main measurement, return to the main
menu, press <Alt>-A, then select C-t.
Press <Al+G, then choose a C vs. t plot to generate a
plot of your C-t measurement.
Note the final capacitance value in the C-t measure­ment (if you require a more-precise value, ‘use the
Display menu selection to display C vs. t informa­tion in numerical form).
Repeats steps 3 through 7 until you obtain a final ca-

8.
pacitance value equal to 95% of the value of Cm ob­tained in step 2. Parameters to adjust are the sample
time and number of samples.

samples and sample time, both of which determine
measurement time.

4.

Choose the various time/delay parameters. Briefly,
time parameters are defined as follows:

Start Delay: An additional delay before the first sam­ple in the C-t measurement is taken.

Sample Time: The time period between individual
samples in the C-t measurement.

Stop Delay: An additional delay after the last sample
before the end of the C-t measurement cycle.

5.

Enter the bias voltage parameters necessary to bias
the device as required both before and during the
sweep. Briefly, bias voltage parameters are defined
as follows:

Default Bias V: The DC bias voltage applied to the
device both before and after the C-t measurement.

Test Bias V: The DC bias voltage applied to the de­vice during the C-t measurement.

6.

Enter the cable calibration filename where indicated
(see paragraph 2.5 for cable calibration details).

7.

After you have entered all your parameters, select
Save, then enter the desired filename at the prompt.

8.

Select OK to return to the main menu.

4.3.3 C-t Measurement Procedure

The step-by-step procedure below, outlines the basic

procedure for making C-t measurements. For more infor­mation on setting up C-t parameters, refer to paragraph

3.3, Section 3. Section 5 covers C-t analysis in more detail.

Step 1: Connect the Test Equipment

Connect the Model 590 to the test fixture or probe station

using the connections outlined in Figure 4-1.

Step 2: Setup C-t Measurement Parameters

From the main menu, press <Alt>-S, and select C-t

1.

setup to display the C-t parameters menu.
Select the various measurement parameters such as

2.
range, frequency, model, and rate, as required. Use
the up/down and left/right arrow keys to move
around the parameter screen.
Enter the number of samples to take for the C-t meas-

3.
urement. Be sure to review the recommendations
discussed in paragraph4.3.2for optimum number of

Step 3: Perform a C-t Measurement

1. From the main menu, press <Ah>-R, then select C-t.
The window shown in Figure 4-12 will be displayed.
Capacitance, conductance, and bias voltage readings
are displayed as shown.

NOTE
Conductance and bias voltage readings are
not available when the lOOO/sec reading rate
is used.

The selections at the bottom of the window allow
you to perform the following:

Start Sweep: Starts the C-t sweep.
Enable/Disable Zero: Toggles Model 590 zero mode

on or off.

Enable/Disable Light: Toggles the light on or off.

Cancel: Exits the window and rehums to the main

menu.

4-11

SECTION 4
Measurement

Run c-t Sweep

Sweep will take 14.4 seconds.

Capacitance

-0.0004 nF

Default Bias

+o.ooo v

< start Sweep > < Enable Zero > < Enable Light >

1 Fimre 4-12.

2. Make sure that the probes are up and that zero is
turned off.

3. Allow the reading to settle, then select Enable Zero
to null any offsets in the system.

4. Place the probes down on the test dots.

5. If you are using a light, bun the light on until the de­vice reaches equilibrium. Turn the light off before
starting the sweep.

6. Select Start Sweep to begin the sweep. After the in­struments are initialized and configured, the win­dow shown in Figure 4-13 will be displayed. Note
that the sweep length, test voltage, and number of
samples in the sweep are displayed, and you can
press any key to abort the sweep.

7. After the sweep is completed, the window shown in
Figure 4-14 will be displayed.

Run C-t Sweea Window

Conductance

-0.0000 mS

II of samples

DC

Bias

00.000 v

I

Test voltage

100

8. Select Done to return to the main menu.

Step 4: Saw and Analyze C-t Data

1. From the main menu, press <Alt>-A, then select C-t.

2. To save your C-t data, press <Ah>-F to select file op­erations, then choose Save C-t Data. Enter the de­sired filename to save the data.

3. Return to theC-t Analysis menu, then press <Alt>-D
to display data arrays or constants. You can also use
<Alt-l’> to print array values or constants on your
printer.

4. To graph C-t data, press <Alt-G> while in the C-t
ANALYSIS menu. Typical C-t graphs include C vs. t
and Zerbst analysis.

c5.000 v

< Cancel >

f

I

4-12

Analysis Constants may require updating to correspond to
new data.

Data calculation by the 590 when 75 or lOOO/sec

rates are selected may take up to 60 seconds.

. ..Buffer filling...

SECTION 4

Measuremrnt

Figure 4-23. C-t Sweep in Progress

NOTE: Analysis Constants may require updating to correspond to

new data.
rates are selected may take up to 60 seconds.

Test Voltage Actual Sweep Time

?gure 4-14.

C-t Sweep Completed Window

Window

Data calculation by the 590 when 75 or lOOO/sec

COMPLETED sweep. 0.4 min.

readings taken.

4-13

SECTION 4

4.4 BTS STRESS CYCLE

A BTS stress cycle can either be performed alone or as
part of the BTS test sequence (paragraph 4.5). Basic stress
cycle setup and measurement are covered in the follow­ing paragraphs. For more complete details on stress cycle
parameters, refer to paragraph 3.4 in Section 3.

4.4.1 Hot Chuck Connections

Before performing a stress cycle, the hot chuck must be
set up per the manufachxef s instructions. The Model
5958 software is designed to work with the Temptronic
Model 03158 Thermochuck, but the hot chuck control file
can be modified for use with other hot chucks, as de­scribed in Section 6.

NOTE
If the chuck is grounded, the Model 590 must
be set up for floating operation. To do so, set
the rear panel ANALOG COMMON
GROUNDING switch to the ungrounded po­sition

ides require and tolerate lower voltages than do thicker

oxides.

Stress Cycle Types

The most common method used is the positive then
negative stress cycle. The positive stress cycle causes the

positive charge to move from its initial position near the
metal gate material across the insulator to the semicon-

ductor. As a check, a negative stress cycle is then applied

to force the charge back to the metal gate material. In
~mne cases, only a positive sties cycle is used, but the ad­ditional negative stress cycle is recommended for maxi-

mum measurement reliability.

With a polysilicon gate material and some etching meth-

ods, the initial distribution of theionic charge may not DC­cur at the metal interface. Consequently, both positive

and negative stressing is essential for these devices. If the

initial charge distribution occurs at the semiconductor in­stead of at the metal, applying negative stress first is

more desirable.

4.4.3 Performing a BTS Stress Cycle

4.4.2 Selecting Optimum Voltage,
Temperature, and Time

Parameters

A bias temperature stress cycle is a combined strews of a
bias voltage applied to a device while at a high tempera­hue for specific period of time. The purpose of the stress
cycle is to cause mobile ions to move across the oxide (in­sulator) of an MIS device. The transit time required for
mobile ion drift varies inversely with the stress voltage
and exponentially with 1 /T.

Stress Temperature

Practical limitations generally dictate the stress tempera­ture. A minimum of 200°C is usually required to keep the
stress time sufficiently short. The maximum temperature
available from commercial hot chucks is usually in the
neighborhood of 300°C to 35OOC. At high temperatures,
the device under test may undergo annealing, which
must be taken into account.

stress Voltage

Step 1: Program BTS Stress Cycle Parameters

From the main menu, Press iAlt>-S, then select BTS
Cycle.
Select the 590 Internal sweep source if you are using
onlv the Model 590. or select the 230-I External
sweep source if you’ are using an optional Model
230-l Voltage Source.
Program the + Stress V, - Stress V, and Stress OFF V
parameters to the desired values. Briefly, these pa­rameters are defined as follows:

+ Stress V: Voltage applied to device during the posi­tive stress cycle.

-Stress V: Voltage applied to device during negative
stress cycle.

Stress OFFV: Voltage applied to device during stress
off cycle.

Enter the desired stress temperature and stress time
parameters where indicated. These parameters are
defined as follows:

Stress Temp: The temperature of the device during
the stress cycle.

The general rule of thumb for selecting a stress voltage is
a value of about lO”V/cm of oxide thickness. Thinner ox-

4-14

Stress OFF Temp: The temperature of the device at
times other than during the stress cycle.

SECTION 4

MtYZ%O-elfIent

Stress Time: The time duration of the stress cycle.

5. Select Save, then save your parameters using the de­sired filename.

6.

Select OK to return to the main menu.

Step 2: Perform the BTS Stress Cycle

1. From the main menu, press <Alt>-R, then choose
BTS Cycle. Select positive or negative cycle, and the
window shown in Figure 4-15 will be displayed. In-

formation shown includes stress time, caoacitance,
DC bias voltage, stress off temperature, p&at tern­peratie, stress on temperature, and current elapsed

--> BTS Cycle Window <--

Stress Time = 1 minutes.

Capacitance

+O.OOOO nF

time. Selections at the bottom of the screen allow you
to select the following:

Start Cycle: Starts the BTS stress cycle,

Cancel: Exits this window and rehwns you to the
main menu.

2. Select Start Cycle, and note that the window shown
in Figure 4-16 will be displayed. While the stress cy-

cle is in progress, parameters that are changing, such
as capacitance, stress time, and current temperatire,
will be continuously updated. You can choose to
abort the cycle at any time, if desired.

3. When the cvcle has been comoleted. the window
shown in Figure 4-17 will be displayed, and you can

select Done to return to the main menu.

Conductance

+O.OOOl mS

Figure 4-15.

BTS Cycle Window

Stress Time expired:

0.0 minutes.

4-15

SECTlON 4
Measurement

Stress Time = 1 minutes.

Figure 4-16.

Capacitance

-0.0000 nF

Conductance

-0.0000 mS

Stress Off Temp

Stress Time expired: 0.0 minutes.

BTS Cycle in Progress Window

Stress Time =

Capacitance

1 minutes.

Conductance

-0.0000 nF +O.OOOO kR

Figure 4-l 7.

4-16

Stress Off Temp

BTS Cycle Completed Window

Present Temp Stress On Temp

1.00 minutes.

SECTION 4

Measurement

4.5 BTS TEST SEQUENCE
MEASUREMENTS

The following paragraphs discuss BTS test sequence con-

nections and outline the basic BTS test sequence meas­urement procedure.

4.5.1 BTS Test Sequence Connections

In order to perform BTS or Zerbst test sequences on, more
than one device, you must either connect a suitable
switching card to your system, or use an automatic probe
sequencer (a probesequencer cannot be used for BTS par­allel tests, however). Connections for several switching
methods are covered in the following paragraphs. When
making connections, keep the following points in mind:

Keep cable lengths as short as possible (five meters

lKCdINm).
Use only 5OQ (RG-58) cables such as the Model 7051.
Match all instrument, cable, and adapter impedances

to as close to 5OQ as possible.
Minimize the total number of connections to avoid
losses caused by inevitable mismatch at connecting
points.
Shield probes as close to wafer as possible, and shield
wafer with Faraday shield.
Perform cable correction for each path before making
measurements (paragraph 2.5).
When possible, connect Model 590 output and input
jacks to card paths as far apart as possible in order to
maximize isolation and minimize stray capacitance.
Use shortest pathways on card where possible.
Select switching parameters so that INPUT is con­nected to gate and OUTPUT is connected to substrate.

Connections for Sequential Stress and No Stress Tests

Figure4-18 shows typical connections using a Model
7062 RF switch card to switch among up to five devices.
Two such cards can be installed in a single Model 705
Scanner to extend the test capability to ten devices. Ten
switch cards can be installed in a Model 706 Scanner, al-

lowing up to 50 devices to be switched with one main-

frame. The Model 7062 maintains a nominal 50R imped­ance to minimize test signal degradation.

Zerbst sequence tests except for BTS parallel test se­quence, which requires parallel switching for the stress
part of the test (see below).

Connections for All Test Sequences

The switch card connections discussed below can be used
for all BTS test sequences (sequential, parallel, and no
stress), as well as for allzerbst test sequences (paragraph

4.6).

Multiplexer Card Connections

A Model 7074D or Model 7075 Eight 1 x 12 3-P& Multi­plexer Card can be used to provide switching for both
parallel and sequential tests, as shown Figure 4-19. (For
smaller systems with fewer devices to be tested, use
Model 7056 cards.) Here, two of eight banks are used to
multiplexorswitchup to 12DUTs, butmultiplexerbanks
can be combined, allowing up to 48 devices to be
switched from one card.

In this configuration, the Model 590 input and output
jacks are connected to Row A and Row 8, while the DUTs
are connected to the bank inputs. Note that these cards
are not equipped with standard BNC connectors, so cus-

torn-dressed cables must be constructed in order to use

this configuration. Cable model numbers are shown on

the diagram.

Matrix Card Connections

A Model 7073 Coaxial Matrix card can aiso be used to
provide the necessary switching functions, as shown in
Figure4-20. Although only 12 DUTs per card can be
switched with this configuration, theMode has two
main advantages over the Model 707413/7075 card dis­cussed above:

Matrix configuration allows greater switching flexibil­ity, especially when adding additional measuring ca­pabilities such as I-V testing.
High-frequency design, resulting in lower crosstalk
and better noise performance when making C-V
measurements.

Note that all test connections shown in Figure 4-18 are

made using Model 705150 (RG-58) BNC cables. Devices

are assumed to be housed in a shielded test fixture or

probe station (not shown on the diagram). The test con-

figuration shown can be used for ail BTS sequence and

Since the Model 7073 is equipped with BNC connectors,
all connections can be made using Model 7051 50R

(RG-58) cabies. Again, DUTs are assumed to be located in

a shieided test fixture or probe station equipped with

BNC connectors.

4-17

SECTION 4
Measurement

Figure 4-18. Typical Model 7062 RF Switch Card Connections

I& + -+ -I- I- -i- -4 -I- c -+ -I -I

!-I 1111111111 I:.

-__---_-_---_---

4-18

SECTION 4

_-------------

Model 7073 Coaxial Matrix Card

A, 1 2 3 4 5 6 7 6 9 10 1: ” ,

ID I

Model 590 C-V Anal

I

Note: This configuration
can be used for all BTS
and Zerbst test
sequences.

?gure 4-X Typical Model 7073 Coaxial Matrix Card Connections

-------------­Note: Cards installed in Model 707 Mainframe

Columns

Devices Under Test

!

A

I

I

Switch Control Files

The switch control files for the three connection examples
above are summarized in Tables 4-1.4-2, and 4-3. The ba­sic procedure for creating these files is outlined below.

(Refer to Section 6 for complete information on switch
control files, and refer to Appendix J for information on
default switch control files.) This procedure requires the

use of a text editor or a word processor that can store files

in pure ASCII format.

1. Run your text editor or word processor.

2. Enter each program code line as shown in the corre­spondlng table. Be sure to enter only the program
code; do not enter the line number or the comments.
Be sure to enter the appropriate cable calibration file­names at the end of each DEVICE statement (see
paragraph 4.5.2 for more information on cable cali­bration).

NOTE
For the parallel BTS test sequence only, in­&de the PARALLEL statement and associ­ated parameters as shown. For all other test
sequences (sequential, no stress, or Zerbst se­quences), the PARALLEL statement is ig­nored.

3.

Save the file in pure ASCII format using the SWC ex-

tension. Be sure to save the file in the \CTRL sub-

directory. An example might be:
C:\KTHLY-CV\MODELSS\CTRL\

MODL7062SWC

4. Enter this switch control filename in the BTS test se­quence menu (see below).

4-19

SECTION 4

Mensurement

Table 4-l. Switch Control File for Model 7062 RF Card Example

Line

1
2 DEVICE 1@17,“CIX”,“NlX”,#CABLEI.CAL
3
4
5
6
7 FINAL @17,“ROX”

NOTES:

1. Model 7062 assumed to be installed in slot I of Model 705.

2. Model 705

3. Cable calibration files, CABLEnCAL assumed to be presenti in \CAL direckoly. See pc,~r.+, 4.52.

Program Code

INIT @17,“ROXA2POX”
DEVICE 2 @J~~,“C~X”,“N~X”,#CABLE~.CAL

DEVICE 3 @17,“C3X”,“N3X”,#CABLE3.CAL
DEVICE 4 @17,“C4X”,“N4X”,#CABLE4.CAL
DEVICE 5 @17,“C5X”,“N5X”,#CABLE5,CAL

primary address = 17.

Comments

Reset 705, Z-pole mode.
Device 1 close, open commands.
Device 2 close, commands. open
Device 3 close, commands. open
Device 4 dose, commands. open
Device 5 close, commands. open
All relays open for safety.

Table 42. Switch Control File for Model 7074DI7075 Card Example

Line

1

2
3 PARALLEL @18,“CA3,B3,A4,B4X”,“NA3,B3,A4,84X”
4 PARALLEL@18,“CA5,B5,A6,B6X”,“NA5,B5,A6,B6X”
5 PARALLEL @18,“CA7,B7,AS,BSX”,“NA7,B7,AS,BSX”
6 PARALLEL@18,“CA9,B9,A1O,BlOX”,“NA9,B9,A1O,BlOX”
7 PARALLEL@l8,“CA11,B11,A12,B12X”,”NA11,B11,A12,B12X”
8 DEVICE 1 @l8,“CA1,BlX”,“NA1,BIX”,#CABLEl.CAL

9 DEVICE 2 @18,“CA2,82X”,“NA2,BZX”,#CABLE2.CAL
10 DEVICE 3 @lS,“CA3,B3X”,“NA3,B3X”,#CABLE3.CAL
11 DEVICE 4 @lS,“CA4,B4X”,“NA4,B4X”,#CABLE4.CAL
12 DEVICE 5 @lS,“CA5,B5X”,“NA5,B5X”,#CABLE5.CAL
13 DEVICE 6 @lS,“CA6,B6X”,“NA6,B6X”,#CABLE6CAL
14 DEVICE 7 @lS,“CA7,B7X”,“NA7,B7X”,#CABLE7.CAL
15 DEVICE 8 @18,“CA8,BW’,“NA8,B8X”,#CABLE8.CAL
16 DEVICE 9 @18,“CA9,B9X”,“NA9,B9X”,#CABLE9.CAL

17 DEVICE 10@18,“CAlO,BlOX”,“NAlO,BlOX”,#CABLElO.CAL
18 DEVICE 11 @l8,“CA1l,B1lX”,“NAl1,B1lX”,#CABLEll.CAL
19 DEVICE 12@18,“CA12,B12X”,“NA12,Bl2X”,#CABLE12.CAL
20 FINAL @lS,“ROX”

Program Code

Jivrr @lS,“ROX”
PARALLEL@18,“CA1,B1,A2,B2”,“NA1,81,A2,82X”

comments

Reset 707.
Parallel commands

Device 1 commands.
Device 2 commands.
Device 3 commands.
Device 4 commands.
Device 5 commands.
Device commands. 6
Device 7 commands.
Device commands. 8
Device commands. 9
Device 10 commands.
Device 11 commands.
Device 12 commands.
Reset 707.

NOTES:

1. Model 7074D/7075 assumed tc, be in slot 1 of Made, 707.

2. Model 707

3. PARALLEL statements are ignored for ail twts except BTS parallel tests.

4. Cable calibration files, CABLEn.CAL, assumed to be present in\CAL directory (see paragraph 4.5.2),

4-20

primary address = 18.

Table 4-3. Switch Control File for Model 7073 Card Example

Line

1
2
3
4
5
6
7
8
9

10

11

1

Program Code

T

INIT @lS,“ROX”
PARALLEL @18,“CAl,B2,A3,B4X”,“NAl,B2,A3,84X”
PARALLEL@18,“CA5,B6,A7,B8X”,“NA5,B6,A7,88X”
I’ARALLEL@l8,“CA9,BlO,Al1,B12X”,”NA9,B1O,A11,B12X”
DEVICE 1@l8,“CAl,B2X”,“NAl,B2X”,#CABLEl.CAL
DEVICE 2 @18,“CA3,B4X”,“NA3,B4X”,#CABLE2.CAL
DEVICE 3 @18,“CA5,B6X”,“NA5,B6X”,#CABLE3.CAL
DEVICE 4 @lS,“CA7,BSX”,“NA7,B8X”,#CABLE4.CAL
DEVICE 5 @18,“CA9,B10X”,“NA9,BlOX”,#CABLE5.CAL
DEVICE 6 @18,“CA11,B12X”,“NAll,B12X”,#CABLE6.CAL
FINAL @18,“ROX”

IOTES:

Model 7073 assumed to be in slot I of Model 707.

: Model 707 primary address = 18.

PARALLEL statements are ignored for all tests except BTS parallel tests.

Cable calibration files. CABLEnCAL assumed to be present in \CAL directory.

4.5.2 Cable Correcting Switching
Pathways

Cable correction is particularly important when using
switching because of the detrimental effects that long ca­bles and switch paths can have on the C-V or C-t meas­urement. The procedure below outlines the basic proce­dure for cable correcting a switching system, and
Figure 4-21 shows typical connections.

For more details on cable correction, refer to paragraph

2.5 and Appendix E.

NOTE
Each pathway to be used in the test should be
cable corrected separately, and the resulting
correction constants should be stored in a
separate cable correction file. The cable cor­rection filenames should be defined in the
switch control file, as covered in paragraph

4.5.1 andSection6.

1. From the C:\KTHLY_CV\MODEL58 directory,
type in the following to run the cable calibration util-

ity:

CABLECAL <Enter>

2. Disconnect the cables for the pathway to be cali­brated from the DUT.

Reset 707.
I’arallel commands.

Device 1 commands.
Device 2 commands.
Device 3 commands.
Device 4 commands.
Device 5 commands.
Device 6 commands.
Reset 707.

3. Make sure that relays for the pathways to calibrated
are closed (be sure that all other relays are open).

4. To load an existing calibration constants file, press
<Alt>-F, then select Load on the menu. Select an ex­isting file, or type in the name of the file.

5. Press <Alt>-E, then select Cable Cal 590 and the de­sired range.

6. If you are cable correcting your system for the first
time, enter the nominal, lOOkHz, and 1MHz values
where indicated (use the <Tab> key to move around
selections). Capacitor #l is thesmaller of two values,
and Capacitor #2 is the large capacitor value for a
given range. Select OK after entering source values
to begin the calibration process.

7. Choose the CALIBRATE selection to perform corn-~
plete cable calibration.

8. Follow the prompts on the screen to complete the
calibration process. During calibration, you will be
prompted to connect calibration capacitors, or to
leave the terminals open in some cases. If any errors
occur, you will be notified by suitable messages on
the screen.

9. Repeat steps 3 through 8 for all Model 590 ranges to
be cable corrected.

10. After calibration is complete, you must save the new
calibration constants in the \CAL directory. To do
so, Press <Alt>-F, then select Save or Save As as re­quired. If you use Save As, be sure to use a filename
with a CAL extension.

11. Repeat steps 2 through 10 for all pathways to be cor­rected, and add the cable correction filenames to the
switch control file where indicated.

4-21

SECTION 4

Measurement

Figure 4-21, Typical Swifch Card Cable Correction Connections

Switch Card

Calibrafion

capacitor

4.5.3 Selecting Optimum BTS Test
Sequence Parameters

C-V measurement and stress cycle parameters must be

carefully chosen in order to obtain valid BTS test se­quence results. Some important considerations on choos­ing C-V parameters are discussed in paragraph 4.2.2.
Similarly, key points on selecting stress cycle voltage,

temperature, and time parameters are discussed in para­graph 4.4.2.

Other points to keep in mind include:

l

When using switching, program a C-V measurement
start delay time sufficiently long to allow for relay set­tling time at the start of each C-V sweep. The settling
time required will depend on the relay settling time of
ihe switch card in question. A start delay time of
50msec should be sufficient for most applications.

l

When using an automatic probe sequencer, program a
C-V measurement start delay time long enough to al­low for probe positioning. Refer to the probe sequen­cer specifications for recommended positioning times.

4.5.4

Parallel BTS Test Measurement

Overload

During the stress portion of a parallel BTS test sequence,
all devices are connected together in parallel, a condition

which could result in a Model 590 overload condition. In
order to avoid a possible inadvertent Model 590 OVER­LOAD error message, Model 590 triggers are disabled to
disable measurement during the stress cycle. Doing so
does not affect the C-V measurements because no meas­urements are made during device stress.

4.5.5 BTS Test Sequence Procedure

Follow the steps below to perform a BTS test sequence.

Step 1: Make Test Connections

Before performing the BTS test sequence, connect your

system as outlined in paragraphs 4.5.1 and 4.5.2.

Step 2: Setup C-V Measurement Parameters

1. From the main menu, press <Alt>-S, and select C-V
setup to display the C-V parameters menu.

2. Select the various measurement parameters such as
range, frequency, model, and rate, as required. See
paragraphs 3.2 and 4.2 for complete details.

3. After you have entered all your parameters, select
Save, then enter the desired filename at the prompt.

4. Select OK to accept parameters and return to the
main menu.

4-22

Step 3: Program BTS Stress Cycle Parameters

From the main menu, Press <Alt>-S, then select BTS
Cycle.
Program the required BTS cycle parameters, as sum­marized in paragraphs 3.3 and 4.3. Be sure to specify
the C-V filename YOU defined in Ste” 2.
After program&g all your stress c&e parameters,
select Save, then enter the filename to save the BTS
cycle parameters.
Select OK to return to the main menu.

Step 4: Program BTS Test Sequence Parameters

From the main menu, press <Alt>-S, then select BTS

1.
Sequence.
Choose the test sequence type: sequential, parallel,

2.
or no stress. The sequential test type runs through
the entire stress-measurement sequence for each de­vice in a sequential manner, while the parallel test se­quence stresses a number of devices in parallel and
then measures C-V parameters for each device indi­vidually. The no stress option is used for C-V only

measurements without stress.

3.

Select the stress cycle type: + then -, - then +, + only,
or - only. + then-applies the positive then negative
stress voltages, -then + applies negative then posi­tive stress, while + only and - only apply only the
positive or negative stress voltages respectively dur­ing the stress cycle.

4.

Select the type of ‘&IN checking. Choose auto if you
are wing a light and wish to determine Cw auto­matically. Choose manual to stop after each C-V
sweep and determine Cwm manually. Select none to
disable Cm checking.

5.

Enter any comments in the indicated field.

6.

Program the number of devices based on your test
requirements. In order to test more than one device
automatically, you must have a switching main­frameorautomaticprobesequencerthatcanconnect
to multiple sets of test dots automatically (a probe se­quencer cannot be used for the parallel stress test,
however). See paragraph 4.5.1 and Section 6 for in­formation on setting up a control file for this equip­ment.
Enter the C-V, stress cycle parameter, and data desti­nation filenames where indicated. These are the files
set up in steps 2 and 3 above. The switch control file­name should also be specified if you are using
switching. The data destination filename defines the
storage location for data taken during a BTS test.
Select Save, then save
rameters under a convenient filename.
Select OK to return to the main menu.

the

BTS stress sequence pa-

Step 5. Run the BTS Test

1.

From the main menu, Press <Alt>-R.

2.

To run the entire stress-measurement sequence, se­lect StTess Sequence. The window shown in
Figure 4-22 will be displayed. Note that capacitance,
conductance, and DC bias are displayed, and that
you can select the following:

Start Test: Starts the BTS test sequence.
Enable/Disable Zero: Enables and disables the
Model 590 zero feature.
Enable/Disable Light: Toggles the option& light on
or off.
Cancei: Exits this window and rehxns to main
menu.

3.

With the probes up, select Enable Zero to null any
system offsets.

4.

Place the probes down on the test dots, then select
Start Test. During the test, pertinent test parameters
willbe displayed on the screen shown in Figure 4-23.
Parameters displayed in the top window segment
include test sequence type (sequential, parallel, or no
stress), number of devices being tested (l-991, the
length of the test sequence, and which device is cur­rently being tested. Parameters displayed in the bot­tom window segment include the start voltage, and
the stop voltage.

During the test sequence, you can press any key to
abort, if desired.

5.

When the test is complete, select Done to return to
the main menu.

Step 6: Analyze BTS Data

1. From the main menu, press <Alt>-A, then select
BTS.

2. Select Display, Print, or Graph to dispiay your data
as required. For example, press <Alts-G to select
graphing options, then select the appropriate option.

4.6 ZERBST TEST SEQUENCE
MEASUREMENTS

4.6.1 Zerbst Test Sequence

Connections

In

order

to perform a Zerbst test sequence on more than
one device, you must use either an automatic probe se­quenceroranappropriateswitchingsystem. Information
on setting up a control file for use with a probe sequencer
is located in Section 6. Paragraph 4.5.1 discusses typical
switching systems that can be used for Zerbst test se­quences. See also paragraph 4.5.2 for details on cable cor­recting switching systems.

4-23

SECTION 4

Measurement

- Run BTS Test Sequence

This is a no stress test sequence.
There is 1 device being tested.

:igure4-22.

Capacitance
COOO.00 pF +ooo.oo us

The sequence

to be run consists of:

1) A C-V sweep for each device

< start Sweep >

Run BTS Test Sequence Window

( Enable Zero > < Enable Light > < Cancel >

--> C-V Sweep in Progress <--

NOTE:

Analysis Constants may require updating to correspond to
new data.

Conductance

u Initial BTS Sweep

DC Bias

04.995 v

I

-igure 4-23.

4-24

Device i/ 1 being tested.

Buffer filling...

< Ait ANY key to ABORT >

BTS Test Sequence in Progress Window

stop Voltage

+s.ooo

SECTION 4

MPmuwmPnt

4.6.2 Selecting Optimum Zerbst
Sequence Parameters

C-V and C-t measurement parameters should be care­fully chosen in order to obtain good results from the
Zerbst test sequence. Paragraph 4.2.2 discusses impor­tant considerations when setting up C-V parameters, and
paragraph 4.3.2 covers methods for determining test
voltages, sample time, and number of samples.

In addition, the following points should be kept in mind:

When using switching, program C-V and C-t meas­urement start delay times sufficiently long to allow for
relay settling time at the start of each C-V or C-t meas­urement. The settling time required will depend on
the relay settling time of the switch card in question. A
start delay time of 50msec should be sufficient for
most applications.
When using an automatic probe sequencer, program
C-V and C-t measurement start delay times long
enough to allow for probe positioning. Refer to the
probe sequencer specifications for recommended po­sitioning times.

4.6.3 Running a Zerbst Test Sequence

Step 1: Make Test Connections

Connect your switch system, as discussed in paragraph

4.5.1.

Step 2: Setup C-V Measurement Parameters

From the main menu, press <AIt>-S, and select C-V
setup to display the C-V parameters menu.
Select the various measurement parameters such as
range, frequency, model, and rate, as required. See
paragraphs 3.2 and 4.2 for details.
After you have entered all your parameters, select
Save, then enter the desired filename at the prompt.
Select OK to accept parameters and return to the
main menu.

Select the various measurement parameters such as
range, frequency, model, and rate, as required. Refer

to paragraphs 3.3 and 4.3 for more information.
After you have entered alI your parameters, select
Save, then enter the desired filename at the prompt.
Select OK to return to the main menu.

Step 4: Program Zerbst Test Sequence Parameters

From the main menu, press <Alt>-S, then select

1.
Zerbst Sequence.
Choose the test sequence type: muitiple C-V, one

2.
C-V, or no C-V. The multiple C-V option can be used

to test a number of dissimilar devices where a sepa­rate C-V data set is required for each device. The one
C-V option can be used to test a number of similar
devices where only one C-V data set is required for
all the devices. The no C-V option should be used in
cases where only C-t measurements are required.

3.

Choose the desired type of GUN checking. (Auto de­termines CMES automatically only if you are using a
light, while manual will cause the program to stop
after each C-V sweep to manually determine ‘Gw.1

4.

Enter any comments in the indicated field.
Program the number of devices based on your test

5.

requirements. In order to test more than one device
automatically, you must have a switching main­frame or automatic probe sequencer,that can connect

to multiple sets of test dots automatically. See para­graph 4.5.1 and Section 6 for information on setting
up a control file for this equipment.

Enter the C-V, C-t, and data destination filenames

6.
where indicated. These are the files set up in steps 2

and 3 above. The switch control filename should also
be specified if you are using a switching mainframe.
The data destination filename defines the storage lo-

cation for data taken during a Zerbst test.

7.

Select Save, then save the Zerbst sequence parame-

ters under a convenient filename.

Select OK to return to the main menu.

8.

Step

5:

Run the

1. From the main menu, Press <Alt>-R.

2. Select Zerbst Sequence. The window shown in
Figure 4-24wilIbedisplayed. Informationdisplayed
includes capacitance, conductance,
lections at the bottom of the window include:

Zerbst

Test Sequence

and

DC bias. Se-

Step 3: Setup C-t Measurement Parameters

1. From the main menu, press <Alt>-S, and select C-t
setup to dispiay the C-t parameters menu.

Start Test: Starts the BTS test sequence.

Enable/Disable Zero: Toggles Model 590 zero on or
off.
Enable/Disable Light: Turns the light on/off.
Cancel: Exits this window and returns to the main
menu.

4-25

SECTION 4

Run Zerbst Test Sequence

This is a multiple C-V test sequence.

1 device being

Capacitance Conductance

-000.00 pF +ooa.m US

2) A C-t sweep for each device

Figure 4-24. Run Zerbst Test Sequence Window

tested.

3. With the probes up, select Enable Zero to null any
system offsets.

4. Place the probes down on the test dots, then select
Start Test. During the test, pertinent test parameters
will be displayed in the window shown in
Figure4-25. Parameters displayed in the top win­dow segment include test sequence type (multiple
C-V, one C-V, or no C-V), number of devices being

tested (l-99), the time duration of the test sequence,
and the current device being tested. The bottom win­dow segment displays test voltage, time expired,
and completion time.

During the test, you can choose to abort the sequence

at any time, if desired.

5. When the test is complete, select Done to return to
the main menu.

Step 5: Analyze Zerbst Data

1. From the main menu, press <Alt>-A, then select
BTS.

2. Press <Alt>-G to select the graphing option, then se­lect the Zerbst option to graph Zerbst data.

3. To disulav eeneration lifetime and eeneration veloc-

L A” v

ity, select option 7 on the graphics menu. Follow the
prompts on the screen to mark the beginning and
end points of the linear region of the Zerbst plot.

Generation lifetime is displayed as zg and is given in
seconds. Generation velocity is displayed as s and is
given in cm/set.

4.7 MEASUREMENT CONSIDERATIONS

The importance of making careful C-V and C-t measure-

ments is often underestimated. However, errors in the
data will propagate through calculations, resulting in er­rors in device parameters derived from the curves. These
errors can be amplified during calculations by a factor of

10 or more.

With careful attention, the effects of many common error
sources can be minimized. In the following paragraphs,
we will discuss some common error sources and provide
suggested methods for avoiding them.

4.7.1

Theoretically, a capacitance measurement using one of

the common techniques would require only that two

leads be used to connect the measuring instrument to the

device under test (DUT)--the input and output. In prac-

tice, however, various parasitic or stray components

complicate the measuring circuit.

Potential Error Sources

c!r”“,:.‘::::..,,~~

Analysis Constants may require updating to correspond to

data

SECTION 4

Measurement

Device /l 1

. ..Buffer filling...

?pue 4-25. Zrrbst Test Sequence in Progress Window

Stray Capacitances

Regardless of the measurement frequency, stray capaci­tances present in the circuit are important to consider.
Stray capacitances can cawe offsets when they are in par­allel with the device, can act as a shunt load on the input
or output, or can cause coupling between the device and
nearby AC signal sources.

When stray capacitance is in parallel with the DUT, it
causes a capacitance offset, adding to the capacitance of
the device under test (GUT), as shown in Figure 4-26.
Shunt capacitance, on the other hand, often increases the
noise gain of the instrumentation amplifiers, increasing
capacitance reading noise (Figure 4-27). Shunt capaci­tance also forms a capacitive divider with COG, steering
current away from the input to ground. This phenome­non results in capacitance gain error, with the C-V curve
results shown in Figure 4-28.

Stray capacitance may also couple current of charge from
nearby AC signal sources into the input of the measuring
instrument. This noise current adds to the device current
and results in noisy, or unrepeatable measurements.

being

tested.

Digital and RF signals are the primary causes of noise in­duced in high-frequency C-V measurements. Stray ca-

pacitance can also affect C-t measurements. Figure 4-29
shows the effects of stray capacitance on a Zerbst plot.

High-frequency Effects

At measurement frequencies of approximately 1OOkHz

and higher, the impedance of Corn may be so small that

any series impedance in the rest of the circuit may cause

errors. Whether such series impedance is caused by in-

ductance (such as from leads or probes), or from resis-

tance (as with a high-resistivity substrate), this series im-

pedance causes non-linearity in the measured capaci-

tance. The resulting C-V curve is, of course, affected by

such non-linearity, as shown in Figure 4-30.

Another high-frequency effect is caused by the AC net-

work formed by the instrumentation, cables, switching

circuits, and the test fixtures. Referred to as transmission

line error sources, the network essentially transforms the

impedance of COLX when it is referred to the input of the

instrument, altering the measured value. Transmission

line effects alter the gain and produce non-linearities.

4-27

SECTION 4
Measurement

. . . .._._____.___.

-L

Figure 4-26.

C

‘X..

“...,

. . . . . . . . . . . . . . . . . . . . Of&,

High Frequky C-V Curve with
Capacitance Offset

Offset

‘..,

\

‘;

i,

//. . . . . . . . ..____ __ _,.- _ -...

”

Normal

Figure 4-29.

Zerbst Plot Affected by Stray Capacitance

Figure 4-27.

-igure 4-28.

High Frequency Curve with Added Noise

‘X,

c

I.,,

‘X . .._________.__.. _..

v

Normal

I....... . ...___._.,,,,

-L

. . . . . . . . . . . . . . . . . . )q,th Gain Error

High Frequemy Cum Resulting from
Gain Error

-.....__.__..______ With Nonlinearity

Figure 430.

Normal

High Frequency Cum Cawd by
Nonlinearity

4-28

SECTION 4

Mensurement

4.7.2 Avoiding Capacitance Errors

The many possible error sources that can affect C-V and
C-t measurements may seem like a great deal to handle.
However, careful attention to a few key details will re­duce errors to an acceptable level. Once most of the error
sources have been minimized, any residual errors can be
further reduced by using the zero feature.

Key details that require attention include use of proper
cabling and effective shielding. These important aspects
are discussed below.

Cabling Considerations

Cables must be used to connect the instruments to the de­vice under test. Ideally, these cables should supply the
test voltage to the device unaltered in any way. The test
voltage is converted into a current or charge in the DUT,
and should be carried back to the instruments undis­turbed. Along the way, potential error sources must be
minimized.

Coaxial cable is usually used in order to eliminate stray
capacitance between the measurement leads. The cable
shield is connected to a low-impedance point (guard)
that follows the meter input. This technique, known as
the three-terminal capacitance measurement, is almost
universally used in commercial instrumentation. The
shield shunts current away from the input to the guard.

Coaxial cables also serve as smooth transmission lines to
carry high-frequency signals without attenuation. For
this reason, the cable’s characteristic impedance should
closely match that of the instrument input and output,
which is usuaIIy 50R. Standard RG-58 cable is adequate

for frequencies in the range of IkHz to more than IOMHz.
High-quality BNC connectors with gold-plated center
conductors reduce errors from high series contact resis-

tance.

Device Connections

Care in properiy protecting the signal path should not
stop at the cable ends where the connection is made to the
DUT fixture. In fact, the device connection is an ex­tremely important aspect of the measurement. For the
fame reasons given for coaxial cables, it is best to con­tinue the coaxial path as close to the DUT as possible by
using coaxial probes. Also, it is important to minimize
stray capacitance and maximum insulation resistance in
the pathway from the end of the coaxial cable to the DUT.

Most devices have one terminal that is well insulated
from other conductors, as in the gate of an MOS test dot.
The input should be connected to the gate because it is
more susceptible to stray signals than is the output. The
output can better tolerate being connected to a terminal
with high shunt capacitance, noise, or poor insulation re­sistance, although these characteristics should still be op­timized for best results.

Test Fixture Shielding

At the point where the coaxial cable shielding ends, the
sensitive input node is exposed, inviting error sources to
interfere. Proper device shielding need not end with the
cables or probes, however, if a shielded test fixture is
used.

A shielded fixture, sometimes known as a Faraday cage,
consists of a metal enclosure that completely surrounds
the DUT and leads. In order to be effective, the shield
must be eiectrically connected to the coaxial shield. Typi­cally, bulkhead connectors are mounted to the side of the
cage to bring in the signals. Coaxial cables should be con­tinued inside, if possible, or individual input and output
leads should be widely spaced in order to maintain in­put/output isolation.

4i7.3 Correcting Residual Errors

Controlling errors at the source is the best way to opti-

mize C-V measurements, but doing so is not always pos­sible. Ways to deal with these error sources are discussed
in the following paragraphs.

One final point regarding cable precautions: Cables can

oniy degrade the measurement, not improve it. Thus, ca-

ble lengths should be minimized where possible, without

straining cables or connections.

Offsets

Offset capacitance and conductance caused by the test
apparatus can be eliminated by enabling zero with the

4-29

SECTION 4

Mt%lSUt?me?It

probes in the up position. These offsets will then be
nulled out when the measurement is made. Whenever
the system configuration is changed, the zero procedure
should be repeated.

Gain and Nonlinearity Errors

Gain errors are difficult to quantify. For that reason, gain
correction is applied to every Model 5958 measurement.
Gain constants are determined by measuring accurate
calibration sources during the cable

Nonlinearity is normally more difficult to correct for than

are gain or offset errors. The cable correction utility sup­plied with the Model 5958, however, provides non­linearity compensation for high-frequency measure-

ments, even for non-ideal configurations such as switch-

ing mahices.

correction

process.

Noise

Residual noise on the C-V curve can be minimized by us-

ing filtering

however, not to apply too much filtering, as doing so

distort the curve. Often, some experimentation may be

necessary to optimize noise reduction and at the same

time keep undesirable effects to a minimum.

when

taking your data. Care must be taken,

will

4.7.4 Interpreting C-V Curves

Even

when all the precautions outlined here are fol­lowed, there are still some possible obstacles to success­fuUyusingC-Vcurves toanalyzesemiconductordevices.

Semiconductor capacitances are far from ideal, so care

must be taken to understand how the device operates.

Also, the curves must be generated under well-con-

trolled test conditions that ensure repeatable, analyzable
results.

Maintaining Equilibrium

The condition of the device when all internal capaci-

tances are fully charged is referred to as equilibrium.
Most high-frequency C-V curve analysis is based on the
simplifying assumption that the device is measured in
eqtibrium. Internal RC time constants limit the rate at
which the device bias may be swept while maintaining
equilibrium. They also determine the hold time required
for device settling after setting the bias voltage to a new
value before measuring Cw-r.

The two main parameters to be controlled, then, are the
bias sweep rate and the hold time. When these parame-

ters are set properly, the normal C-V curves shown in
Figure 4-31 result. Once the proper sweep rate and hold
time have been determined, it is important that ail curves
compared with one another be measured under the same
test conditions; otherwise, it may be the parameters, not
the devices themselves, that cause the compared curves

to differ.

Figure 4-31,

4-30

Accumulation Depletion

I

v substrate

Normal High C-V Curve Results When

Device

is Kept in Equilibrium

Inversion

Analyzing Curves for Equilibrium

There are two primary indicators that can be used to de­termine whether a device has remained in equilibrium
during high-frequency C-V testing. First, as long as a de­vice is in equilibrium, Glrr is settled at all points in the
sweep. As a result, it makes no difference whether the
sweep goes from accumulation to inversion, or from in­version to accumulation, nor does it matter how rapidly
the sweep is performed. Therefore, curves made in both
directions wiIl be the same, exhibiting no hysteresis, and
any curve made at a slower rate will be the same.
Figure 4-32 shows the type of hysteresis that will occur if
the sweep rate is too fast, and the device does not remain
in equilibrium.

Secondly, the curves should exhibit the smooth equilib­rium shape. Deviations from the ideal smooth shape in­dicate a non-equilibrium condition, as in the examples re­sulting from too short a hold time shown in Figure 4-33.

c

SECTION 4

Measurrment

c

. .

”

IL

Figure 4-33. Curve Distortion when Hold Time is too

Short

Initial Equilibrium

Biasing the device to the starting voltage in the inversion
region at the beginning of a C-V measurement creates a
non-equilibrium condition that must be allowed to sub­side before the C-V sweep begins. This recovery to equi­librium can take seconds, minutes, or even tens of min­utes to achieve. For that reason, it is generally advanta­geous to begin the sweep in the accumulation region of
the curve whenever possible.

N- ‘..

%,

.,, . . . . . . . z __...._,,_,

IL

”

*-... . . .._____._____

Figure 4-32. Curve Hysteresis Resulfing When Sweep

is too Raaid

Still, it is often necessary to begin the sweep in the inver­sion region to check for curve hysteresis. In this case, a
light pulse, shone on the device, can be used to quickly
generate the minority carriers required by the forming in­version layer, thus speeding up equilibrium and shorten­ing the hold time.

One way to ensure equilibrium is initiallv achieved is to
monitor the capacitance level at the init& bias voltage
and wait until it decays to its equilibrium level.

4-31

SECTION 4

4.7.5

The dynamic range of a zeroed high-frequency measure­ment will be reduced by the amount of the zero value. For
example, if, on the 200pF range, you were to suppress a
value of IOpF, the dynamic range would be reduced by
that amount. Under these conditions, the maximum
value the instrument could measure without overflow­ing would be 190pF.

A similar situation exists because of cable correction. For

example, the maximum measurable value on the 2nF
range may be reduced to 1.8nF when using cable correc­tion. The degree of reduction will depend on the amount

of correction necessary for the particular test setup.

4.7.6

Dynamic Range Considerations

Series and Parallel Model

Equivalent Circuits

A complex impedance can be represented by a simple se­ries or parallel equivalent circuit made up of a single re­sistive element and a single reactive element, as shown in
Figure 434. In the parallel form of (a), the resistive ele­ment is represented as the conductance, C, while the re­actance is represented by the susceptance, B. The two to­gether mathematically combine to give the admittance,
Y, which is simply the reciprocal of the circuit imped­ance.

dividual components are not. We can demonstrate this
relationship mathematically as follows:

R+jX=A

To eliminate the imaginary form in the denominator of

the right-hand term, we can multiply both the denomina­tor and numerator by the conjugate of the denominator
as follows:

R+jX=-xx

Performing the multiplication and combining terms, we
have:

R+jX=----

If we assume the reactance is capacitive, we can subs&
h&-l /WC, for the reactance and WC, for the susceptance
(C, is the equivalent series capacitance, and C, is the

equivalent parallel capacitance). The above equation
then becomes:

R-jX

-=
WC,

In a lossless circuit (Rand G both O), C, and C, would be
equal. A practical circuit, however, does have loss be­cause of the finite values of R or G. Thus, C,and C, are not
equal-the greaterthe circuit loss, the larger the disparity
between these two values.

G+jB

G + jB

G-jB

G*+@

G - joCp

GZ + ozcpz

G-jB
G - jB

+-J.-uy+

G

Figure 4-34.

In a similar manner, the resistance and reactance of the
series form of (b) are represented by R and X, respec­tively. The impedance of the series circuits is Z.

The net impedances of the equivalent series and parallei
circuits at a given frequency are equal. However, the in-

4-32

Series

and Parallel Impedances

Series and parallel capacitance values can be converted to
their equivalent forms by taking into account a dissipa­tion factor, D. D is simply the reciprocal of the Q of the cir­cuit. For a parallel circuit, the dissipation factor is:

D=L=G

Q

WC,

For the series circuit, the dissipation factor is defined as:

D=$=oC,R

Model

Parallel, C,, G

Series C., R

Table 4-4. Converting Series-parallel Equivalent Circuits

Zapacitance

!auivalent Circuit

Xssiuation Factor

Zooversion

G

DLL&G-

-c2­CP

--Ye

Q $z

D=&=oC,R

cp =c,

I+@

SECTION 4

Measurement

cesistance
:onductance
3onversion

R= D2

(l+@)G

G= D2

(l+@)R

By using the dissipation factor along with the formulas

summarized in Table 4-4, you can convert from one form

to another. Note that C, and C, are virtually identical for
very smaU values of D. For example, if D is 0.01 C,and CP
are within 0.01% of one another.

Example:

Assume that we make a 1OOkHz measurement on a par&
lel equivalent circuit and obtain values for C, and G of

160pF and 30@ respectively. From these values, we can

calculate the dissipation factor, D, as follows:

D=

7x(100 x 103) (160 x lo-“)

D = 0.3

The equivalent series capacitance is then calculated as

follows:

c, = (1 + 0.09) 160pF
C, = 174.4pF

4.7.7

Device Considerations

30 x 10-6

The Model 5958 software uses a three-element model

(Figure 5-13) to compensate for series resistance. The se­ries resistance, I&-s, is an analysis constant that can be
entered using the Display Analysis Constants selection

in the C-V Analysis menu (see paragraph 5.4). The de-

fault value for Rseru~s is 0, which means that data will be
unaffected if the value is not changed.

The Model 5958 software determines the displayed value

of RSWES by converting parallel model data from the

Model 590 into series model data. The resistance value

corresponding to the maximum high-frequency capaci­tance in accumulation is defined as RSERN. See paragraph

4.7.6 for a detailed discussion of parallel and series
model.

Device Structure

The standard analysis used in the Model 5958 assumes a

conventional MIS structure made up of silicon substrate,
silicon dioxide insulator, and aluminum gate material.
You can change the program for use with other types of
materials by modifying the MATERIALCON file, as dis­cussed in Appendix A. For compound materials, a
weighted average of pertinent material constants is often
used. Typical compound materials include silicon nitride
and silicon dioxide in a two- or three-layer sandwich.

Series Resistance

Devices with high series resistance can cause measure­ment and analysis errors unless steps are taken to com­pensate for this error term. The high dissipation factor
caused by series resistance can cause errors in Cox meas­urement, resulting in errors in analysis functions (such as
doping concentration) that use COX for calculations.

Device Integrity

In order for analysis to be valid, device integrity should
be checked before measurement. Excessive leakage cur­rent through the oxide can bleed off the inversion layer,
causing the device to remain in nonequilibrium indefi­nitely. In this situation, the inversion layer would never

4-33

SECTION 4
Measurement

form completely, and CMOU and C-t measurements would
be inaccurate.

Charge Spreading

Most problems associated with C-t measurement repro­ducibility are caused by charge spreading. Basically,
charge spreading occors when the oxide surface beyond
the gate edge becomes charged during measurement,
causing inversion beyond the gate. The resulting ex­tended inversion layer causes distorted C-t data, result­ing in measurement and analysis errors.

The solution to the charge spreading problem is a guard
ring capacitor which is concentrically located around the
gate test dot. A DC bias voltage is applied to the guard
ring to compensate for charge spreading. Since the gate is
extremely sensitive to noise, the guard ring voltage must
be very well filtered. One low-noise, low-cost solution is
to use two 9V batteries and a switch to provide the guard
ring voltage with appropriate polarity for the type of ma­terial being tested.

4.7.8

Light Leaks

High-quality MOS capacitors, which are the subject of
C-V and C-t analysis are excellent light detectors. Conse­quently, care should be taken to ensure that no light leaks
into the test fixtures or probe station. Typical areas to
check include door edges and hinges, tubing entry
points, and connectors or connector panels.

Thermal Errors

Accurate temperature control is important for accurate
C-V and C-t data. For example, the intrinsic carrier con­centration, m, doubles for every PC increase in ambient
temperature. In order to minimize the effects of thermal
errors, keep the device at a constant temperature during
measurement, and repeated measurements should all be

made at the same temperature.

Test Equipment Considerations

4-34

SECTION 5

Analysis

5.1 INTRODUCTION

This section contains detailed information on data analy-

sis features of the Model 5958 software, and it contains
the following information:

5.2 Default Constants and Symbols Used for Analy­sis: Summarizes numerical constants and symbols
discussed in this section and used by the Model 5958
software.

5.3 Obtaining Basic Analysis Information from High­frequency C-V Curves: Discusses how to determine
device type; accumulation, depletion, and inversion
regions; and Cox and Cm from high-frequency C-V
CUN~S.

5.4 Loading and Saving Data: Discusses loading data,
saving data, as well as importing data into other
programs such as spreadsheets and word proces­sors.

5.5 Graphical Analysis: Covers the graphics control
menu, cursor operation, and overlaying curve data.

5.6 C-V Data Analysis: Details the various C-V analysis
operations, including displaying and printing
analysis constants and graphing C-V data.

5.7 C-t Data Analysis: Describes C-t analysis features
such as displaying and printing analysis constants
and graphingc-t and Zerbst Data.

5.8 BTS Data Analysis: Gives details on BTS analysis
functions, including displaying, printing, and
graphing data.

5.9 References and Bibliography: Sununarizes works
cited in this section and also lists recommended
reading for C-V, Zerbst, and BTS analysis and re­lated topics.

5.2 DEFAULT CONSTANTS AND

SYMBOLS USED FOR ANALYSIS

52.1

Constants used by the Model 5958 are defined for silicon
substrate, silicon dioxide insulator, and aluminum gate

material. These constants are defined in the
MATERIALCON file, which can be modified for used
with other material types (refer to Appendiw A). Default

material constants are summarized in Table 5-l.

5.2.2

Calculated data symbols used by the various analysis ai­gorithms are summarized in Table 5-2.

Default Constants

Calculated Data Symbols

5-l