Operating instructions

IMPROVING MEASUREMENT QUALITY
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In the following cases the cantilever has to be replaced in order to re-estab-
lish high image quality:
• 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.66). 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
Measurement containing tip artefacts