Agilent 4142B Product Note

DC Characterization of Semiconductor
Power Devices

Product Note 4142B-1

Practical Applications Using the
HP4142B Modular DC Source/Monitor

HEWLETT
PACKARD

-

Table of Contents

1. Introduction ..................................................................................................

2. Application Examples

2.1 Automatic Extraction of Parameters..

2.1.1. Automatic Measurements with a Module

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

...................................................... 2

Selector.. ........................ 2

2.1.2 Enhancing Automatic Measurements by External Relay Control

2.2 Extending the Measurement Range

2.2.1. 2000 V Measurement

2.2.2. lOA/20V

2.2.3. 20A/ 1OV

Measurement.. ................................................................

Measurement

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

2.2.4. High Power Measurement (250 mA x 100 V, 125 mA x 200

......................................................... 6

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

V)

Appendix

Subprograms used in 2.1.1

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

2

....

4
6

8

10

...... .12

14

1

1. Introduction

1

The HP 4142B Modular DC
Source Monitor is a high speed,

highly accurate, computer-

controlled dc parametric meas­urement instrument for charac­terizing semiconductor devices.
This product note uses an HP
4142B to show practical meas­urement examples that character­ize semiconductor power devices.

Table 1. The HP 4142B plug-in modules

Model number / Acronym /

HP 4 I420A
Source Monitor Unit

HP414215

Source Monitor Unit
HP 4 l422A

High Current Unit

HP41423A

HP 4 I424A

HP41425A
Analog Feedback Unit

1-V range

HPSMU

­MPSMU

HCU 4OpV-IOV, 20j1A-IOA

4OpV-2OOV. 20fA- I A

4OpV- I OOV, 20fA- I OOmA ,

2 mV- I OOOV, 2 pA- I OmA

Example configuration for measurements of
devices on a wafer.

You can mix and match different plug-in
modules for unique application requmments

2. Application Examples

2.1 Automatic Extraction of Parameters

2.1.1. Automatic Measurements

with a Module Selector

When you extract the dc param-

eters of a power device, you
need to change the configuration
for almost every parameter since
each parameter requires a unique
configuration of the instruments
and measurement circuit.
However, if the configuration
can be changed automatically,
the dc parameters can also be
extracted automatically.
The HP 16087A Module Selec­tor lets you change the configu­ration programmatically, thus
freeing you from cumbersome
configuration changes. This sec­tion shows a versatile example
for automatically extracting the
dc parameters of a MOSFET.
The setups needed to extract
each parameter are shown in
Figure 1. The circuits in Figure

2 are functionally the same as
in Figure 1, but electronically
different. The setup in Figure
2 uses the module selector
to automatically change the
configuration.
An example of automatically
extracting parameters by using
the module selector is shown in
Figure 3. The program listing
of this example is shown in

Figure 4.

2

Parameter

BVdss. ldss

circut

Figure 1. Parameters for MOSFET and

measurement circuits

MODULE SELECTOR

f,Du ,HC:+- ~

Figure 2. You can easily change the
connection of measurement modules
with the module se!ector

l*** Parameter Measurement CMOS) **a*

Jds(on) 5.02 (V)
?ds(on) 2.51 (ohm) (Id=2A, Vg=lSJ) [ HCU 1
i/th 4.98 (VI (Vd=lBV) r HCU I
Jth (by AFU) = 3.512 (V)

JfS

lgss 4.17E-11 (A)

Bvdss 493.5 (V)

ldss .023216 (A) (Vd=320V) [ HVU

.913 (S) t HCU 1

(Id=2A, Vg=lSV) [ HCU 1

(Vd=lBV, Id=lmA) 1 MPSMU 1
(Vg=20V) [ MPSHU 1

(Id=lBmA) [ HVU 1

1

FIgwe 3. Simple measurement results
for auto extraction of parameters.

Let’s examine the benefits of
using an HP 4142B to measure
each parameter. For the ON
state resistance measurement of
a power MOSFET, a source of
high current and a monitor for
high resolution voltage are neces­sary. The HP 41422A High Cur­rent Source/Monitor Unit (HCU)
can force a maximum current of

1OA and can make high resolu­tion measurements with a
minimum voltage of 4OpV.
Therefore, the HCU can make
precision measurements of the
ON state resistance, which is an
important parameter of power
MOSFETs.
There are several ways to ex­tract the threshold voltage (Vth)
of a MOSFET. In this example,
two methods are used. The first
method measures the J%l-Vg
characteristics, then draws a
regression line and extracts as
threshold voltage the X-axis

value at the cross point of the

regression line and the X-axis.
The second method is much
faster. An HP 41425A Analog
Feedback Unit (AFU) and two
HP 41421B Source/Monitor
Units (SMUs) are connected in a

feedback loop. The AFU moni-

tors the output voltage of one
SMU, which is connected to the

gate of the MOSFET, and moni­tors the current of the other
SMU, which is connected to the
drain. When the drain current
reaches a user-specified value,
the voltage value of the gate
(Vth) is extracted. Vth is usually
measured by a combination of a
High Power SMU (HPSMU) and
a Medium Power SMU
(MPSMU).
To measure the leakage current
of a high power device, high
voltage output and low current

3

10

OPTION %ASE 1

20

COM /Meas/ @Hp4142,INTEGER Hcu,Hvu,Smu,Hpsmu

30

COM

40 !

/Disp/ Vth,Vth afu,Yfs,Igss,Bvdss,Idss,Vdson,Rds(

50 ASSIGN @Hp4142 TO
60

Hpsmu=2 ! slot

70

Smu=3 ! slot 3

-

723

2

80 Hcu=5 ! slot 5
90 Hvu=7

100 !
110 Hcu connect
120 Vds-on
130 Vth­140 Smu connect
150 1gss
160 Vth afu
170 Hvu-connect
180 Idss
190 Bvdss

200

Disp res mos

- - 210 END

! slot 7

50-90 Initialization.
110-130 Connect HCU and measure Vds (on), Rds (on), Vth, yfs.
140-160 Connect SMU and measure Vth with AFU.
170-190 Connect HVU and measure Idss and BVdss.

Figure 4. Measurement program

measurements are necessary.
The HVU not only forces a
maximum voltage of lOOOV, but
measures current with 2pA
resolution.
For breakdown voltage measure­ments, the HVU has the quasi­pulse measurement mode’ for
precision measurements by
minimizing the duration of the
breakdown condition.

1 Quasi-pulse measurement mode
The measurement sequence of this mode
follows:
i) Force current specified by the user

as current compliance.

ii) Monitor the voltage and calculate the

voltage slew rate.

iii) When the Device Under Test (DUT)

is in the breakdown condition, the
current starts flowing rapidly and the
voltage slew rate becomes flat. The
unit detects this point, waits a user­specified delay time, and measures
the output voltage.

iv) After the measurement, the output

voltage is rapidly returned to the
start voltage.

4

2.1.2. Enhancing Automatic
Measurements by Exter-

nal Relay Control

You can open or short the out­put of the SMU by using the fol-

lowing methods:

OPEN Make the output current

0 A in current force mode.

SHORT Make the output voltage

0 V in voltage force mode.
For example, use these methods
to open the base when you
measure the BVceo of a bipolar
transistor or to short the gate
(grounded) when you measure
the BVdss of a MOSFET,
without ever having to remove the

SMU from the base or the gate.

When you measure certain para-

meters of a bipolar transistor or
a MOSFET, the emitter of the
bipolar transistor or the source
of the MOSFET are usually con­nected to the ground unit
(GNDU) and not to the SMU.
Conversely, the connection be­tween the GNDU and the device
needs to be open when measur­ing other parameters, such as
Icbo of a bipolar transistor.
Opening and shorting the SMU
make the configurations
trouble-free.

This example shows how to
programmatically measure the

Icbo parameter of a power
bipolar transistor by using an
external relay. The example uses

the Voltage Source (VS) of a

Voltage SourceNoltage Meter

Unit (VSNMU) to control the

external relay.

Before the measurement, make a

measurement module as shown

lcbo = 1.7128E-7 (A)

in Figure 5 by fixing the relay
to the universal module (P/N

16088-60010). The default condi­tion for the external relay is closed
By forcing a specified voltage to
the relay from VS, the external
relay is opened, and the connec­tion between the GNDU and the
emitter is opened. Figure 6 shows

the measurement circuit, Figure

7 shows the measurement results,

HVU

7

Figure 6. Measurement circuit

VS

0

~ i

$

GNDU

Figure 5. Measurement module

User 1

1

Figure 7. Measurement result

Caps

Idle

and Figure 8 shows the program.
An external relay used with a
module selector (as shown in
Figure 9) is an easy way to
make even more versatile and
automatic measurements. For

instance, the connection to the
GNDU and the transistor emitter
can be opened to extract the
Icbo parameter of a transistor.

OPTION BASE 1

10

20

ASSIGN @Hp4142 TO 723

30

Hpsmu=2

40

Hvu=7

vsl=18

50
60

vc=400

70
80

Iccomp=.Ol

90

V-off=12

100

110
120
130
140

150
160
170

180
190

200
210

!
OUTPUT @Hp4142;
OUTPUT @Hp4142;"FMT";5
OUTPUT @Hp4142;"DV";Vsl,O,V off
OUTPUT @Hp4142;"DV0~;Hpsmu,0~0,1ccomp
OUTPUT @Hp4142;"DV~~;Hvu,O,Vc,ICCOrnp
OUTPUT @Hp4142;"MN";1,H~~
OUTPUT @Hp4142;"XE"

ENTER @Hp4142 USING "#,3A,12D,X";A$,Icbo

OUTPUT @Hp4142;"CL"

PRINT "Icbo = ";Icbo;"(A)"
END

! vc = 4oov

! IC camp = 1omA
! relay disconnect voltage

"CN";H~~,H~~~U,VS~

5

20-90 Initialization.

110 Set the output switches of measurement modules to ON.
120 Specify format of the measurement data.
130 Open the relay OPEN by forcing 12 V to the relay from VS.
140 Ground the base.
160-200 Perform the measurement and display the results.

-

Frgure 8. Measurement program

Figure 9. Auto extraction of parameters with
external relay and module selector

2.2. Extending the
Measurement Range

Since the HP 4142B can
programmatically connect an
HPSMU, HCU, or HVU to a
device pin by using the module

selector, you can make very

wide-ranged measurements, as

shown in the white area of
Figure 10. In addition, you can
use two HPSMUs, HCUs, or
HVUs to extend the measure­ment range into the range indi­cated by the diagonal lines in

Figure 10.
In this section, the measurement
examples for devices that work
in the extended voltage/current
area of Figure 10 are shown.

6

m Standard Conflguratlon

I

^^

3

z

a,

5

0

IOOm i

10m

1

20f Lb

4ou

10 100 200

Voltage N)

MP 41420A. 414ZlB,4i422A. 41423N

Fss$ Expandable

(Depend on the configuration of plug-in units)

*l : &her, "s,"g cnly 2 HVUs

1K ZK

2.2.1. 2000V Measurement

One HVU can make breakdown
tests of up to 1OOOV. You can

increase the maximum voltage to
2000 V by using two HVUs in
differential mode. The extended
range is shown by diagonal lines

in Figure 11. This is very useful
for breakdown voltage measure­ments or current leakage meas­urements of 8OOl9OOV power
transistors and SSRs (Solid State
relays), both of which are used
for switching power lines.
This example shows how to
measure breakdown voltage of

an 800 V power transistor. The
measurement result, measure­ment circuit, and measurement
program are shown in Figures

12-14.
One HVU is connected to the
collector and the other is con­nected to the emitter. First,

- 1OOOV (BVl) is applied to the
emitter. Since the HVU is unipo­lar, you need to change the

polarity of the HVU to negative

t

* (iOV.2ON

* (ZOV. 1OA

/(14V. i6A)

1

i 1

I

t .(20V.l4A)

Voltage N)

* (4OV. 700mA)

1 Standard conflguratlon

ya: Expandable

. (BOV, 350mA)

* (iOOV, 250mA)

in advance. Second, by using the
break down command, a quasi­pulse is applied by the HVU
connected to the collector. Then

Figure 10. Current and voltage range covered
by the HP 4142B.

(HP 41420A. 414218. 41422A. 414238)

~

(Depend on the confIguratIon of plug-In units)

I

ii1 : &tier, using crly 2 HVUs

Figure 11. Expanding the current and voltage
range with two HVUs in series.

the voltage at the collector (BV2)
is measured. By subtracting BVl
from BV2, you can get the actu-

al breakdown voltage.

a

2.2.2. lOAl20V Measurement
One HCU can output or measure
up to 10AllOV. You can extend
this range to lOAl2OV by using
two HCUs. The extended range
is shown by diagonal lines in

Figure 15. The extended meas-

urement range makes it possible

to evaluate devices that drive dc
motors for cars.
This example shows how to
measure Id-Vg characteristics by
sweeping Vd from OV to 20V.
The measurement circuit, meas­urement result, and measure­ment program are shown in
Figures 16-18.

One HVU is connected to the
drain and the other is connected
to the source, and an SMU is
connected to gate. The measure­ment mode is set to dual pulse
sweep measurement mode. The
HCU is designed to output only
pulse, so to perform a OV to 20V
sweep measurement, the sweep
measurement is made two times:

OV to 1OV and IOV to 20V.
In the first measurement, the
HCU connected to the source
forces OV while the HCU con­nected to the drain forces sweep
outputs varying from OV to 1OV.
The Id parameter is measured in
every step.
In the second measurement, each
voltage value that was applied to
the gate in the first measurement

minus ten volts is applied to the to 20V to the device. By sweep-

gate. The HCU connected to the ing Vd from OV to 2OV, these

drain forces sweep outputs vary- two measurements give the Id­ing from OV to 1OV. This is Vd measurement as shown in
equivalent to sweeping from 1OV Figure 17.

i Standard configuration

* uov, 2ON

(ZOV. ION

? (4OV. 7OOmAi

10m

ZOf

10 100 200

Voltage N)

41

(HP 414ZOA. 414218. 41422A. 41423A)

y/A Expandable

(Depend on the conflguratlon of plug-l? units)

(6OOV. 20mA)

.

r

L (IOOOV. 12mAi

: r(iZOOV, lOmA)

.

:\

(2OOOV. 6mA)

/ i

1K ZK

Figure 15. Expanding the current and
measurement range with two HCUs in series.

I

HCU

A

A

‘i

GNDU

Figure 16. Measurement circuit

HCU

2.2.3. 20AllOV Measurement
The previous example shows a

lOAl2OV measurement by two
HCUs in series. By using two
HCUs in parallel, you can extend
the measurement range up to
20A/lOV. The measurement
range extended by this configu­ration is shown by diagonal lines
in Figure 19.
This example shows how to
measure Ic-Vc characteristics of

the power bipolar transistor. The

Ic parameter can easily exceed

10A. The measurement circuit,

measurement result, and meas-

urement program are show in

Figures 20-22.

The HCUs are connected in

parallel between the collector

and emitter as shown in Figure

20. The measurement mode is

set to 2 channel pulsed sweep

mode to synchronize the HCUs.

The two HCUs are current

sources that sweep current

values from OA to 10A. Current

from the two HCUs flow into

the bipolar transistor, which is

equivalent to a sweep from OA
to 20A. By measuring the vol­tage at the top of either HCU,
you can get Ic-Vc characteristics
with 20A.

1 Standard conflguratlon

s$$ Expandable

(4OV. 700mA)

. (BOV, 350mA)

’ (IOOV. 250mA)

9 (ZOOV. 125mN

1;

10m

i

T

ZOf 1,

4ou 10 100 200 1K 2K

, I

Voltale (jli

* (4OOV. 50mN

lc-vc

10

(HP 41420A. 414218. 414228, 41423A)

(Depend on the configuration of plug-In units)

(6OOV. 20mA)

Figure 19. Expanding the current and
measurement range with two HCUs in

parallel.

4

SMU

GNDU

Figure 20. Measurement circuit

2 -4 6 I@

vc (VI

Fieure 21. Measurement result

(xEE1

2.2.4. High Power Measurement
(250mA x lOOV, 125mA x 200V)
By connecting two HPSMUs in
series or in parallel, you can
make very high power measure­ments. This is effective for
measuring the channel-on break­down voltage of EL (Electra Lu­minescence) and PDP (Plasma
Display Panel). The measure-

ment range extended by this
configuration is shown by di­agonal lines in Figure 23.

This example shows how to

measure Id-Vd characteristics in
the high power measurement
range by connecting two HCUs
in parallel. The measurement cir­cuit, measurement results, and
measurement program are shown
in Figure 24-26.
The white area inside the broken
lines in Figure 25 shows the
measurement range that can be
covered with one HCU. Using
two HPSMUs lets you extend
the measurement range into the
area indicated by diagonal lines.

0

r

IMOb’. ‘OOmkl

1

V

1

II

GNDU

0

HPSMU

12

0 HPSMU x 1
;///: riPSMli x 2

(1OOV. 250mA)

1

100

Figure 23. Expanding the current and
measurement range with two HPSMIJs in
pXalld.

V

1

,,,,,,,,,y;{V 125mA) ~

////,?

I!!!!

HPSMU

Figure 24. Measurement circuit

Figure 25. Measurement result

Id-Vd

01 ““““““‘A” 1 ”

B I0 20

Vd (VI

36 40

(xE0)