Philips CM200 User Manual

User Guide for the

Philips CM200

FEG TEM

cm200 user guide 2009

THE RULES:

1. If in doubt, CLOSE THE GUN VALVE.

2. Do not touch a control if you don’t know exactly what it will do.

3. Never force anything beyond finger strength.

4. If in doubt, ask for help.

Contact staff for this instrument:

Katie Levick, Sean Lim, Paul Munroe

cm200 user guide 2009

Contents

1. IMPORTANT PARTS OF THE PHILIPS CM200 TEM ........... 4

2. CHECK cm200 STATUS ..................................................... 8

3. TURN THE FILAMENT UP ................................................. 9

4. LOAD THE SPECIMEN ..................................................... 10

5. OBTAIN AN IMAGE ........................................................ 12

6. SET THE EUCENTRIC HEIGHT ......................................... 13

7. FOCUS THE IMAGE ......................................................... 13

8. MOVE AROUND THE SPECIMEN ................................... 14

9. CHECK THE MINOR ALIGNMENTS ................................ 15

10. INSERT AN OBJECTIVE APERTURE ................................ 17

11. RECORD AN IMAGE ON PHOTOGRAPHIC FILM ........ 18

12. RECORD A DIGITAL IMAGE ......................................... 19

13. EXCHANGE SPECIMENS ................................................ 20

14. END THE SESSION ........................................................ 21

Appendix a: Using the double tilt holder .............................. 22

Appendix b: Diffraction patterns .......................................... 24

Appendix c: X-ray analysis ................................................... 25

Appendix d: X-ray mapping/line scans ................................. 32



cm200 user guide 2009

1. IMPORTANT PARTS OF THE PHILIPS CM200 TEM

Exposure

To the left of the column:

field emission gun (FEG)

condenser aperture 1

condenser aperture 2

Goniomete

RST WBL

Tilt Holder Intensity

side viewing window

focus stage leve

main stage leve

objective aperture

diffraction

aperture

fine

dewar

liquid N

for EDS system

specimen holde

liquid N container fo cold finge

focus stage

viewe

gun valv e

control

Close Open

main viewing window

Film camera exposure

button

Goniometer

Exposure RST WBL

check camera

switch is set to CM

Tilt Holder Intensity

α-tilt control β-tilt control

(with floor pedal)

GUNVALVE

Z XY

oystick

intensity fine

adjustment

on/off

intensity

control

beam

wobbler

cm200 user guide 2009

The gun valve:

The Philips cm200 TEM uses a field emission gun (FEG) which provides very high resolution but requires more care than a standard TEM filament. It is very important that a high vacuum is maintained in the gun chamber at all times. The gun chamber is sealed off from the rest of the column using the gun valve. The gun valve must be closed whenever a specimen is being exchanged. If you have a problem with the operation of the instrument or if you need to leave the room, please close the gun valve by turning the control knob slowly clockwise to the closed position.

The computer screen:

The cm200 contains many manual controls, such as focus and magnification. However, many functions are controlled via a computer interface, using the “softkeys” at the edges of the screen. To select a particular function press the softkey next to the appropriate function title. To leave a page or function, press the READY button at the lower right hand side of the screen. In most cases, this will take you back to the HR-TEM BRIGHT FIELD page.

The functions described here are those required for most users. The other functions must not be used unless you have received appropriate training.

DO NOT PRESS A SOFTKEY IF YOU DON’T KNOW WHAT IT DOES.

INT ZOOM

INT LIMIT

HR-TEM BRIGHT FIELD

HT spot 1

focusstep 1

defocus -4.30um

plate auto meter XXX s exp no stoc

X: -141.61 um Y: -78.72 um Z: 135.69 um

: 0.00 d

B: 0.00 d

1000x

200k

350nm

E7773 50

MODES

PARAMETERS

UTOCON-1

COMPUSTAGE

RSET DEFOC

MEASURING

VACUUM

TEM CAMERA

HR-TEM BRIGHT FIELD page

¾ This page allows access to most of the functions of the microscope.

¾ The page is made up of three columns. The central column shows the

magnification, spotsize, focus step, film exposure information, film stock levels, and stage positions.

¾ The right-hand column allows access to other pages in the program

via the softkeys. The most commonly required are COMPUSTAGE, VACUUM STATUS and MODE SELECTION (MODES).

cm200 user guide 2009

COMPUSTAGE page

¾ The

COMPUSTAGE allows stage position to be monitored and

controlled. Stage positions can be stored and recalled. The central column on this page contains the same information as on the HRTEM BRIGHT FIELD page.

¾ To store a stage position, select a number in the right-hand column

on the monitor using a softkey (when selected, the number is highlighted). Press the STORE softkey to save the position.

¾ To return to a saved position, select the appropriate number and

press the RECALL softkey on the right-hand side of the page. The stage will automatically move to that position.

¾ To clear a saved stage position, select the appropriate number and

press the CLEAR softkey on the left-hand side of the page.

¾ To clear all saved stage positions, press the CLEAR ALL softkey twice

(located on the left-hand side of the page).

¾ The COMPUSTAGE page also contains functions for setting eucentric

height (A-WOBBLER) and for returning the specimen to zero tilt (RESET AB). The RESET AB softkey must always be pressed before a specimen is removed.

COMPUSTAGE REGISTER CONTROL

COMPUCTRL

Z DISPL = 0

Z DISPLAY USER REAL

CLEAR

CLEAR ALL

XY RECALL-

RESET AB

-WOBBLER

HT spot 1

focusstep

plate auto meter XXX s exp no stoc

X: -141.61 um Y: -78.72 um Z: 135.69 um

: 0.00 d

B: 0.00 d

1000x

200k

350nm

-defocus 44.30um

E7773 50

STORE

RECALL

cm200 user guide 2009

VACUUM STATUS page

¾ The

VACUUM STATUS page shows a diagram of the vacuum system.

The status of the vacuum can be read at the top of the screen. Below the diagram of the vacuum system is a series of pressure readings, including the IGP (ion getter pump) reading.

P1: 32 P3: 34

P2: 49

¾ Before the gun valve is opened, the IGP reading must be less than 27

and the VACUUM STATUS must be ‘READY’.

MODE SELECTION page

¾ The modes page allows the user to select the TEM mode to be used.

Usually this is HR-TEM. The CONFIGURATION page can be accessed from this page.

CONFIGURATION page

¾ This page contains information on the state of the microscope

(STANDBY or OPERATE) and on the extraction voltage. As the filament is turned up, the change in extraction voltage (“Actual”) can be monitored on this page.

IGP: 5

STANDBY

EXTR LIMIT

CONFIGURATION

FEG CONTROL

State: STANDBY Time: 0 min

: 4.5 kV

ctual: 2.29 kV

DISPLAY

FIL OFF

cm200 user guide 2009

2. CHECK cm200 STATUS

1. Log in to the EMU Booking System on the PC.

2. Check that the vacuum is OK by confirming that both the UHV and HV indicators on the far right side of the panel are illuminated. If not, check with EMU staff.

3. Go to the VACUUM STATUS page (from the HR-TEM page, press the VACUUM softkey). Check that the vacuum status is READY and that the IGP is less than 27. If not, check with EMU staff.

4. Return to the HR-TEM page (press READY).

5. Check that the High Tension indicator on the right side of the panel is lit. If not, check with EMU staff.

6. Fill the liquid nitrogen dewar and place it under the cold finger. You must wear safety glasses and protective gloves when handling liquid nitrogen.

7. Ensure that condenser aperture 4 and objective aperture 7 are selected and that the diffraction aperture is out (swing shift to the right).

condenser aperture objective aperture diffraction aperture

cm200 user guide 2009

3. TURN THE FILAMENT UP

1. Press the MODES softkey and then the CONFIGURATION softkey to go to the CONFIGURATION page.

2. Turn the filament knob on the right-hand side of the display screen slowly clockwise (three or four clicks at a time).

Note: If the voltage is increased too quickly, the kV value will freeze and you will need to seek assistance from EMU staff.

Monitor the extraction voltage on the screen. When the voltage approaches its limit (~4.5 kV), you will hear a beep. Make sure you reach the maximum possible voltage by turning the knob a few more clicks. The voltage will usually reach 4.48 kV.

3. Press the READY button and then the HR-TEM softkey to return to the HRTEM BRIGHT FIELD page.

High tension

On Off

Filament

cm200 user guide 2009

4. LOAD THE SPECIMEN

There are two specimen holders available:

1) A single-tilt holder for conventional imaging and EDS analysis.

2) A low-background double tilt holder for crystallographic studies and specialised EDS analysis (see appendix a).

When you begin your cm200 session the single-tilt holder will normally be in the microscope.

Remove the single-tilt holder:

1. CHECK THAT THE GUN VALVE IS CLOSED. If not, close it by turning the switch slowly clockwise.

2. Pull the specimen holder out until it cannot be pulled any further (~8cm).

3. Rotate the holder clockwise as far as it will go (~120º).

4. Pull the holder gently out of the airlock. Take care not to knock the specimen holder against the airlock walls as it is released.

5. Place the specimen holder in the support. Do not touch the brass part of the specimen holder with your fingers.

6. Lift the specimen securing clamp using the special tool.

7. Load the specimen into the recessed ring, then gently lower the securing clamp using the special tool.

8. Rotate the specimen holder slightly and gently tap it to ensure that the specimen stays in place.

Insert the single-tilt holder:

1. CHECK THAT THE GUN VALVE IS CLOSED. If not close it by turning the switch slowly clockwise.

2. Check the IGP reading by going to the VACUUM STATUS page. The IGP reading should be less than 27. If not, check with EMU staff.

cm200 user guide 2009

3. Insert the rod gently into the specimen airlock. Orient the rod so that the large key peg is at the 11 o’clock position. Push the rod into the airlock until you feel a stop and the red light on the airlock illuminates (this indicates that the airlock is being pumped). After the pump has started it is often useful to gently wiggle the rod, which allows it to be inserted another few millimetres.

4. Wait until the red light has turned off.

5. Rotate the rod anti-clockwise (~120º) keeping a firm grip on the holder. The vacuum will ‘grab’ the rod when it gets to the 6 o’clock position.

6. Guide the rod as it enters the airlock. The key peg should slide into the slot on the airlock. Monitor any change in vacuum by noting the IGP value. (The IGP value may rise above 27 during rod insertion – it must be 27 before operation).

cm200 user guide 2009

+ 25 hidden pages