© ICSPI Corp. 2007-2021
nGauge AFM User Manual 2.0
51
If these materials are not available, there are a few quick ways to discharge a sample:
•
Simply taking them off the sample platform and placing them in contact with a conductor,
especially one connected to earth ground (such as a faucet or fume hood) can discharge
the sample effectively
•
Placing a conductor (piece of metal) near the region of interest (if possible). A metal
washer works well
•
Placing a conductor (piece of metal) underneath he sample
If the sample still produces false engages, try scanning a clean piece of metal to discharge the
tip itself.
7.3.5.
Fine Z Drift and Fine Z Not Centered
It is possible that the sample topography is not centered around the middle of the Fine Z range,
which could result in image clipping. The Approach tab displays a graph with the Fine Z
position. If it appears that most of the image data is at the lower or higher end of the Fine Z
range, you can click
Show Advanced Controls
and increase or decrease the Coarse Z to
center the data. In some cases, you may even need to
Disengage
and then re-
Approach.
7.3.6.
Setpoint Not Tracked
If the amplitude and/or Fine Z signals appear to be noisy and the setpoint is not being tracked,
click on
Disengage
. Then select
Show Advanced Controls
and increase the Z Coarse value
to 0.2 V.
Click on
Approach
. If the setpoint is still not tracked, it is possible that the sample is electrically
charged.
