6
6. Z-height adjustment
•
Move edge of sample and set the objective lens current to 5.72 using focus control. Focus the sample
using the Z-height adjustment screw on the specimen holder entry port.
Note: An objective lens current of 5.72 is the optimal setting for minimum spherical aberration.
You may also focus sample using wobblers method or minimum contrast method for the image
focus.
7. Voltage center
•
Move edge of sample.
•
Turn on [HVM] (HV MODULATION, right panel). The image feature may oscillate.
•
Adjust BEAM TILT (right sub panel) to minimize the vibration of the feature.
•
Turn off [HVM] (right panel).
•
Repeat the alignment procedure a few times because the beam tilt and objective stigmatism correction
have disturbed the condenser stigmatism corrections. In general, completing the alignment procedure
twice will be sufficient.
Z-height adjustment