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Equipment Contact

Dr Richard Cutting
richard.cutting@manchester.ac.uk
Room B.08B
Ext. 0161 275 0395
Int. 50395

Equipment Details

Philips XL30 ESEM-FEG equipped with EDAX Gemini EDS system.

Using the XL30 ESEM

Starting a session

When you first arrive at the start of a session, the ESEM sample chamber should be under 'HiVac' mode, with the vacuum status listed as 'Vac OK'.

There are two pole pieces ('bullets') containing the final aperture commonly available for use with the XL30, please ensure that you have liased with the equipment contact to ensure that the correct bullet is in place for your requirements.

If you require the backscattered electron detector (for elemental contrast) or low vacuum GSED (for very low vacuum work), please ensure that you have contacted the equipment contact prior to the start of your session.


Loading a sample

1. Ensure the beam is off

Press the button marked with the beam strength (eg 20kV) so that it isn't highlighted.

2. Press detectors and then CCD to switch to the camera inside the chamber.

3. Click Vent and then ok. When the vacuum status changes to 'idle', then it is safe to pull the stage out.

Sample chamber may state that it is at idle, but the chamber will not open. DO NOT FORCE SAMPLE STAGE. Instead, press Vent for a second time and wait for the stage to release.

4. You can now load a sample stub onto the sample holder.


Turning the ESEM on

1. On the stage tab, move the sample away from (0,0) to ensure no debris clogs up the bullet when pumping down, should a bubble form and then burst.

2. Maximise the Vacuum window, and assuming that you want to use ESEM mode as opposed to the HiVac SEM mode (with which you will need to check with Steve that the right bullet is in), check the following settings:

  1. Mode : H2O
  2. Purge : Auto
  3. Pressure : 0.5 torr

Now click Pump and then select No PLA.

At the moment, the ESEM will generate an error saying that the VCU Controller is down. Click Ok to the error pop up box (this may reoccur) and then press the VAC button on the ESEM stand (not on the computer!) Should an error occur, ensure that the Vac button on the ESEM stand is always illuminated You will now need to click Pump again Wait until Vac OK appears on the screen.

3. Activate the Detectors drop down menu and select GSE.

4. Move the stage back to (0,0).

5. Press the Beam button (after selecting the desired kV) but do not press ok on the pop up message box. Should an error pop up here, ensure that the HT button is illuminated on the ESEM stand. Activate the Scan drop down menu and select TV Increase the contrast under the Beam tab until the sample stage is visible. Now is a good time to align the Beam with the sample. Expand the Beam tab on the right and alter the Gun Shift so that the beam is centred, using the circular movement tool on the tool menu bar. Click and hold the right mouse button to bring the sample into focus. Switch to Slow Scan 1 and fine tune the focus. Now click ok on the pop up message box. To change the sample astimagmatism (if focus is as good as it will get but shows a preferred orientation) then hold down shift and gain use the righthand mouse button.

6. To take an image press F2 and this will freeze the image (snowflake will be highlighted) then select in/out at the top of the screen and then image. Find your folder, type in a short filename and then hit save. It should then be saved into your folder so that it will appear on the computer behind you. To unfreeze the image press the snowflake button.


7. To take an edx spectrum load edax genesis (blue circle icon) up on the computer screen on the far left. Ensure that the EDAX detector is wound in so that it is just visible on the CCD detector screen at the top middle (5.5cm on scale). Press collect and should get severel hundred counts per scond at the bottom left, otherwise if not enough the detector is not in or the sample is too uneven etc..


How the XL30 ESEM works

SEM Schematic

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