Nanosurf easyScan 2 AFM, Operating Instructions Manual

Page: 62 / 164

I
MPROVING MEASUREMENT QUALITY
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• images in the color map charts consist of uncorrelated lines only.
• images appear blurred.
- First follow the suggestions in section Image quality suddenly deteriorates
(p.81). If these do not help, the cantilever should be changed.
If all peaks in the image have the same, usually triangular shape, the tip is
no longer sharp and has to be replaced. The measured structure is called a
tip artefact.
Adjusting the measurement plane
Ideally, the sample surface and the XY-plane of the scanner are all parallel.
But in most cases, the sample plane is tilted with respect to the XY-plane of
the scanner. In this case, the sample cross section in the X* measurement
direction has a certain slope. The Line graph chart in figure
Maladjusted
slope is an example. This slope depends on the direction of the X* direction
and therefore on the rotation of the measurement, as shown in figure Slope .
This slope is undesirable for several reasons:
• It makes it difficult to see small details on the sample surface when the
Average, Plane fit or higher order filters can not be used.
• The Z-Controller functions less accurately, because it has to compensate
for the sample slope.
Measurement containing tip artefacts