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MEASUREMENT OPERATION
TMPM5200-2
5-145
he
6.
Click on t
button in the Fback Filter/Hz selection box and select 0.5
from the pull-down menu.
ch the feedback circuit does not oscillate while watching an
7.
Double-click on the Current/nA input box; then, when the numerical value is
highlighted, enter 1 using the keyboard and finalize the 1 by pressing the Tab
key.
Current/nA specifies the tunneling current flowing between the specimen surface
and the cantilever tip. You have to change the Current/nA value while watching an
image during scanning. Here, enter 1.000 provisionally.
Fback Filter/Hz is the parameter that determines the response speed of the feedback
circuit. The larger the specified value is, the faster the response speed becomes, thus
producing a sharp image, but the feedback circuit easily oscillates. Usually, select
the highest speed at whi
image during scanning.
8.
Click on the
button in the Loop Gain selection box and select 8 from the
pull-down menu.
Loop Gain is the parameter that determines the gain of the feedback circuit. The
larger the specified value is, the higher the gain becomes, thus producing a good
back circuit easily oscillates.
image of a topographic specimen, but the feed
9.
Click on the
button in the Display Source 1 selection box and select
Topography from the pull-down menu.
10.
Click on the Advanced button on the Advanced tab window.
The Advanced Control window is displayed.
