Veeco Dimension 3100, Руководство пользователя

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Force Imaging
Force Calibration Mode
210 Dimension 3100 Manual Rev. D
Figure 13.2d Anatomy of a Force Curve
The horizontal axis plots the tip movement relative to the sample. By extending the Z-axis piezo
crystal, the tip descends toward the sample and the tip-sample distance decreases. The descent plots
from right-to-left in yellow on the NanoScope display monitor. By retracting the Z-axis piezo
crystal, the tip ascends away from the sample and the tip-sample distance increases. The ascent
plots from left-to-right in white on the NanoScope display monitor.
Cantilever deflection plots on the vertical axis of the graph. When the cantilever deflects downward,
it plots on the graph’s downward vertical; when the cantilever deflects upward, it plots on the
graph’s upward vertical.
2
3
4
5
1
Piezo extension
Piezo retraction
Cantile
v
er deflection
6
Up
Do
wn
1
2
5
6
7
3
4
7
Piezo extends; tip descends.
No contact with surface yet.
Attractive forces near surface
As tip presses into the surface,
cantilever bends upward.
Piezo retracts; tip ascends until forces are in
equilibrium with surface forces.
Cantilever relaxes downward.
Piezo continues retraction; tip ascends further.
Cantilever bends downward as surface
attraction holds onto the tip.
As tip continues its ascent, tip finally
breaks free of surface attraction. Cantilever
rebounds sharply upward.
As piezo continues retracting, tip continues
its ascent. No further contact with surface
this cycle.
pull tip down.