5 OPERATION
5-28
EM210F-1
■
Others
If the specimen is contaminated, it is difficult to focus the image correctly, and
photographs obtained will be obscure even though the image is properly focused. In
order to prevent contamination by the electron beam, avoid irradiating the specimen for a
long time.
Do not use a magnification higher than that necessary for resolving the feature of interest
adequately, and photograph the image with an exposure time as short as possible (two to
four seconds will be adequate).
5.3.2 Illumination System Alignment
1.
Select “Maintenance” on the “TEN Controller” main menu to display the
“Alignment Panel for Maintenance” screen.
Fig. 5.29 “Alignment Panel for Maintenance” screen
2.
Set the magnification to 5,000 times.
3.
Set the SPOT SIZE knob (L1-
③
) to 1.
4.
Converge the electron beam using the BRIGHTNESS knob (L1-
⑥
).
5.
Select “Gun” on the “Alignment Panel for Maintenance” screen.
6.
Manipulate the SHIFT knobs (L1-
⑧, R1-③
) or DEF/STIG knobs (L1-
⑩
, R1-
④
) to center the beam.
7.
Depress the “Wobble-Anode” button on the “Alignment panel for Mainte-
nance” screen.
8.
Manipulate the SHIFT knobs and DEF-STIG knobs so that the beam
converges and diverges concentrically.
9.
Set the SPOT SIZE knob (L1-
③
) to 5.
10.
Depress the BRIGHT TILT switch (L1-
⑥
) or set the “DEF Select” switch on
the “Alignment Panel for Maintenance” screen.
11.
Center the beam using the SHIFT knobs (L1-
⑧, R1-③
).
12.
Repeat step 2 to 8 above until the beam deviation from the screen center
when the SPOT SIZE knob setting is changed becomes minimum.
