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2.
If all the parameters of SEM is correct, and the alignment of final aperture is well, astigmatism
correction is adjustable in range, but the system can not acquire a clear image, it is need to
change an aperture.
Note:
If the astigmatism correction is out of range, it is suggested to change another aperture.
When check the astigmatism, it better to use the sample with well conductivity.
3.
Rotate the knob of the aperture holder can change a new aperture.
4.
The aperture holder have 3 marked line that indicate 3 apertures. Each marked line indicate
one aperture.
5.
After change an aperture, the user must readjust the alignment of Final Aperture.
6.
After finish the alignment of Final Aperture, the user must readjust the astigmatism correction.
Caution:
The aperture holder can be taken out by rotate counterclockwise. Therefore, it is
dangerous that take out the aperture holder when the column is kept in vacuum. When rotate
the knob of aperture holder counterclockwise, please pay attention to observe the first marked
line which close to the column. Do not rotate it over much. If observe the screw thread of holder,
stop rotate.
Caution:
The aperture holder can be taken out only the column is kept in atmospheric pressure.
Summary of Contents for A63.7069
Page 21: ... 20 Control Panel ...
Page 41: ... 40 4 10 Dither ...
Page 43: ... 42 4 12 4 Pseudo Colors Source Pseudo Colors 4 13 Options ...
