Veeco Dimension 3100, Manual

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Force Imaging
Force Calibration (Contact Mode AFM)
220 Dimension 3100 Manual Rev. D
Motor
The Motor menu allows you to withdraw or manually control the tip position using the stepper
motor. Selecting Step Motor opens a dialog box containing the following buttons:
• Tip Up : This command moves the tip up by the SPM step size displayed inside the
window.
• Tip Down : This command moves the tip down by the SPM step size displayed inside
the window.
13.4 Force Calibration (Contact Mode AFM)
13.4.1 Obtaining a Good Force Curve
Figure 13.4a Typical Force Calibration Curve
Figure 13.4b Piezo Positions for Typical Force Curve
To minimize or calculate the contact force between the tip and sample, obtain a good force curve
which shows the typical features displayed in the example curve in
Figure 13.4b . However, the
force curve rarely looks “typical” right after invoking Force Calibration mode. This section
(Z Scan start -Ramp size)
Setpoint
Slope = Volts of Deflection/nanometers (or volts) of piezo travel
+
Cantilever Off Surface
(Z Scan start) Z Piezo Voltage
1 2
3
4
5
6
V csmin
Cantile
v
er Deflection
V
oltage
Piezo travel
direction
Position
number
Up
1
Up
2
At
Bottom
3
Down
5 6
Down
4
Up Up