JEOL JSM-6390 LA, User Manual

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SEM manual ETHZ v1.4
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Appendix
A1) Adjusting the SNS (Sample Navigation System)
The SNS image is not very accurate, yet it should drive the stage within a couple millimetres of the target. The
calibration of this system is regularly checked by the manager. However, if you want to check and possibly
adjust it (because someone screwed it up…), please,
strictly follow this procedure:
•
You MUST load the 32 mm sample holder (for round mount) . NEVER use the THIN SECTION
holder , as it will result in a wrong calibration of the SNS!
•
Ensure the sample chamber is fully opened , up to the back stop.
•
You MUST first press the button “Snap” before “Adjust”! It will move the stage and take a snapshot.
•
An adjustment is only required if the sample is not centred (yellow line NOT in the middle of the
stage holder). To perform the adjustment (see also Fig. A1 ):
o
Press the button “Adjust”. Ensure the Holder Size “32 mm” is selected.
o
Adjust the X and Y position of the stage using the button on the console (in X/Y mode) and
recentre the holder (yellow line is in the exact middle of the 32 mm holder.
o
Move the horizontal and vertical green lines so that it matches the edges of the round mount.
o
Try rotating the sample using the rotation knob. If the adjustment is properly done, the sample
should remain in the centre and the green lines should always touch the round mount edges.
o
Press “Set” when the holder is perfectly centred.
•
Press again “Snap” to take another picture with the new adjustment, and then “OFF” to turn off SNS.
•
Lower again the stage to Z = 30 mm before closing the chamber!
Figure A1. Adjusting the Sample Navigation System (SNS).