Veeco Dimension 3100, Manual

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TappingMode AFM
Basic TappingMode AFM Operation
136 Dimension 3100 Manual Rev. D
Automatic Tuning
For most purposes, the Auto Tune function will suffice.
• Verify the starting parameters. The nominal resonant frequency of a probe can be found
on the probe box label. Ensure the start and end frequencies correlate with this value.
• Click Auto Tune . The computer and controller begin automatic tuning (see Figure
9.2a ).
Figure 9.2a Auto Tune Control Panel
Manual Cantilever Tuning
With Force Modulation or Fluid Tapping applications, it may be useful to tune the cantilever
manually.
Note: More than one type of cantilever exists. Cantilevers can have different
dimensions and different resonant frequencies. Certain parameter values,
particularly the center frequency and the sweep width used in the following
example, apply to a particular cantilever type. In the following example,
nominal parameter values will vary depending on the actual cantilever used.
1. In the Cantilever Tune panel, set the Drive frequency parameter to a value near the center
of the resonant frequencies range specified for the wafer. For example, if the frequency range
is specified as 240—420 KHz, select a drive frequency of
330 KHz .
2. Set the Drive amplitude to 200 mV .
3. Set the Sweep Width to the same value as the Center Frequency .
4. The Sweep Width must be large enough to cover the frequency range specified for the
wafer.
5. Zero the Setpoint .
6. Set the Amplitude limit to 2.5V .
7. Center the peak on the frequency sweep plot shown on the display monitor using the Zoom
In and Offset commands after identifying the maximum amplitude peak with the lowest
frequency in the frequency response plot.