５
MEASUREMENT OPERATION
TMPM5200-2
5-147
3.
Click on the
button in the Sensitivity selection box in the Channel B
rame; then select 5 from the pull-down menu.
f
■
Approachi
Mov
until the value of the tunneling current
b
when the tunneling current reaches the value specified in Current/nA.
The
1.
C
.
You can monitor the Log I signal.
ng
e the cantilever closer to the specimen
ecomes the value specified in Current/nA. The cantilever movement automatically stops
following is the procedure for approaching.
lick on the Probe button on the SPM Parameters window
The Tip window will appear.
2.
Specify each parameter according to the following procedure.
rd. Press the Tab key on the keyboard
to finalize the value.
b.
Click on the
a.
Double-click on the Current/nA input box. When the value in the box is
highlighted, enter 1 using the keyboa
button in the Feedback Filter/Hz selection box; then select
1.0 from the pull-down menu.
ing, have been determined. To prevent the cantilever from
c.
king on it.
3.
B
scan
If th
ltage, it is
eady been completed. So, approaching will not
Now, the tunneling current and the response speed of the feedback circuit, which
are used for approach
colliding with the specimen, set Feedback Filter/Hz to a value higher than that for
image observation.
Deselect Tip Retract by clic
efore performing approaching, confirm that the voltage applied to the Z
ner reaches the maximum voltage (+150 V or 200 V).
e voltage applied to the Z scanner does not reach the maximum vo
judged that the approaching has alr
start even if you click on the Approach On button on the Tip window.
In such a case, check the following points.
