Calibration, Maintenance, Troubleshooting and Warranty
Calibration of “A” Scanners for Atomic-scale Measurement
306
MultiMode SPM Instruction Manual
Rev. B
15.9
Calibration of “A” Scanners for Atomic-scale
Measurement
The “A” scanner is the smallest scanner, with a total travel of approximately 0.4µm along each axis.
Its compact design lends excellent stability for atomic scans, and requires slightly modi
fi
ed X-Y
calibration procedures. These are treated in this section. The procedure for X-Y calibration
described below is essentially the same as those described in
–
manual; however, they substitute graphite or mica atoms for the pits seen on silicon calibration
references. A similar procedure is outlined in
of this manual for STM imaging of
graphite. Please note that this procedure applies only to X-Y calibration of atomic-scale imaging.
The Z-axis is calibrated in the normal way using a silicon calibration reference as described in
above.
15.9.1
Prepare Sample
Perform the calibration with either highly ordered pyrolytic graphite (HOPG) or mica. Mica should
be used for contact AFM; HOPG for STM. Cleave both mica and HOPG to obtain a good
fl
at
surface. Cleave by adhering tape to the surface and pulling it off; this produces a fresh surface of
atoms having a regular lattice.
1. Place the sample on a puck, then attach to the scanner cap.
2. To obtain contact AFM atomic-scale images, try the following
Realtime
parameter settings:
Panel
Parameter
Setting
Scan Controls
Scan Size
12nm
X offset
0.00nm
Y offset
0.00nm
Scan angle
0.00 deg
Scan rate
61.00Hz
Number of samples
256 or 512
Slow scan axis
Enabled
Z limit
440V
Feedback Controls
Integral gain
12.00
Proportional gain
4.00
LookAhead gain
0.00
Setpoint
0V
Other Controls
AFM mode
Contact
Input attenuation
1x
Interleave Controls
Interleave mode
Disabled
Channel 1
Data type
Height
Highpass
fi
lter
3–4
Lowpass
fi
lter
1