Instruction manual

Calibration, Maintenance, Troubleshooting and Warranty
Contact AFM Troubleshooting
318 MultiMode SPM Instruction Manual Rev. B
Selecting a large Scan size and a high scan rate for a few scans can “sweep” an area clear.
Decreasing the Scan size to image within the “swept” area can improve the quality of atomic
images.
Finally, adjust the force exerted on the sample. Engagement requires a positive deflection of the
cantilever, but the microscope will operate at much lower forces and lowering the force sometimes
improves the image quality. Decrease the Setpoint in small increments to lower the force. Once
engaged and the Scan size is significantly increased, sometimes more force is necessary to keep the
tip scanning on the sample surface. Increase the Setpoint in small increments to increase the force.
15.11.11 Force Calibration command does not seem to work
Most often, the Force Cal. command will not provide a meaningful display, when first invoked. Z
scan start and Scan size as well as Setpoint affect the position and shape of the curve, and will
probably require adjustment to achieve a useful display. The negatively sloped sensitivity line
should, however, always be straight for a proper force curve.
15.11.12 Image features appear washed out
The Data Scale in the active Channel panel might be too large. Decrease the scale for more
contrast between features.
15.11.13 Image is only black and white
The Data Scale in the active Channel panel is to small. Increase the scale for less contrast between
features.
15.11.14 Image goes white
If, when using an “A” scanner, the image goes white after a couple of scans and the Z center voltage
is still within range, check the Realtime Planefit parameter on the active Channel panel. When
using an “A” scanner, it should be set to Line or Offset instead of None. In general, this will be a
problem anytime there is a significant amount of drift in the Z center voltage, but drift is especially
prevalent with “A” scanners.