Removed sample, then replaced it at 90 degrees from previous position. Retuned. Tip is now resonating at 333.12kHz. Tune plot looks soft. May have picked up something of significant mass during last use, or while sitting in non-cleanroom ambient. Using it to scan anyway. Will see what comes of it. Noticed output signal is over 10V. This seems high.
Tuning with Loren. Usually target amplitude is 3V because that’s what DI says. Hit autotune. Went into manual tune window. This tip has multiple resonances (not ideal). Setpoint should also be 3V. Trace should be stable, and max should meet the setpoint. This one’s stable. If there’s drift, try moving tip around in holder, increase drive amplitude to drive it a little harder, or just replace tip. Want tip of trace to be 1 hashmark below top of plot. To do this change drive amplitude. Select drive frequency, go 3 left arrow clicks. This will set the offset. This keeps us from imaging at resonance, where things can look underwater. Notice output signal is dancing around. Select quit. Now the output signal should be between 3.6 and 3.9V. Now our output signal is steady at 3.8. We’re now doing free space oscillation. When tip is on the surface, we’re damping out the amplitude. Want to be about 3 when on the surface.
Note, I didn’t have to take sample out at all if I wanted to change scan orientation. Just change scan angle by 90 degrees.
Changing channel 2 to amplitude. It’ll show us deviations of amplitude as the tip interacts with the surface. Track controller delay time effect. Is tip interacting with surface? This trace will show.
Decrease scan size to 1 micron. Start at 3Hz scan rate. Exited interleave controls because we won’t be using them (they’re disabled anyway).
Noticed: front gap under head is too far down. Need to keep head level to keep components free. Raised fron of head some.
Tails in retrace image show amplitude is too high. Adjusted.
Tip velocity is 2X scan size times scan rate. Start at 1 micron, then go up to 10 micron. Start at 3 Hz, then moving to .5 brings trace and retrace back together.
Restart from the top down a few times to let the piezo settle in.
Need to check both y and x direction. We’re swinging nearly 440 (z limit) plus or minus 220 volts in each direction) in y direction, and stepping slowly in x. So we do need sample orientation.
Capture calibration option in the capture dropdown menu is based on using the right standard. Might have to tune up or reorient the standard to a more perfect 90 degrees. Have to be close to dead on for this to work well. Parameters are stored under microscope settings. It’ll come up with a table of values. May not even be able to have tip engaged when looking for this table. Can change units (Metric to volts). Set at max volts: 440V (metric is a very particular number depending on this tool’s piezo material makeup – 13.4 microns here). This number might change after calibration.
calibrate scaner. simplifieed instructions don’t cover all parameters, but tunup may not require update of all parameters. Need full scale calibration procedure.
analyze section of imge. 9.121 as distance for 9 nm distance. Within error or standard itself!