nGauge AFM User Manual
14
When you are finished with the AFM, go to the
Approach
tab and click
Disengage
to safely
disengage the tip from the sample. After the disengage routine is completed (a few seconds), hold the
Retract
button to rapidly move the sample downwards to the point where there is sufficient separation
between the sample and the tip to safely remove the sample. It is advisable to
always disengage and
retract
when finished with the AFM lest any external disturbances (such as accidentally bumping into
the stage) cause the tip to crash into the sample.
Caution:
the tip is extremely fragile so please avoid
crashing the tip into the sample while removing the sample.
4.4 Analyzing Data
Once a scan is complete, users often want to extract some quantitative data about the sample,
like the height or width of a specific feature, or the RMS roughness of the surface. These measurements
are best acquired using Gwyddion, a powerful AFM post-processing program that is explained in section
5.0 Post-Processing.
5.0 Post-Processing
5.1 Gwyddion
Gwyddion is free and open-source software for AFM image post-processing. It can be
http://gwyddion.net/download.php
. The nGauge user interface can save images in a
Gwyddion-supported format (.gsf) which can then be dragged and dropped into Gwyddion to open
them. The
gives detailed descriptions of the program's capabilities, but below
are some useful functions that are commonly used:
Data Process --> Level -->
Polynomial Background
If there is any tilt or curvature in the image, this function will help
remove it. You can specify the polynomial degree in the horizontal and
vertical directions.
