Instruction manual
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(1) Beam Alignment
Beam Alignment is necessary in order to align the electron beam down the center of the
electron optical column and through the center of the objective lens aperture.
(a) Open the Alignment dialog window by clicking the
button on the Control Panel.
(b) Click the Beam Align button in Alignment dialog window. A circular image will appear.
(c) Make adjustments with the alignment knobs (X and Y) or the mouse so that the circular
image appears in the center of screen.
Adjust
Circular image
(d) Turn off the Beam Align mode (click Off button in Alignment dialog window).
NOTICE: If a circular image does not appear even under the highest contrast setting, click
Reset All button in the Alignment dialog window and change the first condenser lens
to 16, and then carry out beam alignment. Afterwards, change the first condenser
lens to the desired value (normally, 5) and repeat the beam alignment.
If the electron beam is not focused near the specimen surface, the circular image may
be distorted or partially blocked. In such a case, release the beam alignment (click
Off button in the Alignment dialog window) and roughly adjust focus.
If the circular image does not appear at all, perform a mechanical alignment.
Assuming that you have done the beam alignment and presented an image at the
center of the monitor. If the image is circular, it is fine. But if it is not a circular
image or a part of the circle is missing even if setting higher contrast , try mechanical
alignment following the instructions given in section 3.12.
(2) Aperture Alignment
Aperture Alignment is necessary to align the electron beam through the center of the objective
lens.
(a) Set the magnification to about 5,000× and position a point of interest in the center of the
display.
(b) Focus the image and correct astigmatism.
(c) Click
Aperture Align
button in the
Alignment
dialog window and make adjustments so
that the wobbling motion of the image is minimized.
(d) Turn off the Aperture Align mode (click
Off
button in
Alignment
dialog window).
NOTICE: When you changed focus widely, it is recommended to perform degaussing of the
3.4.2