Veeco Dimension 3100, Manual

Page: 331 / 376

Calibration
SPM Calibration Overview
Rev. D Dimension 3100 Manual 311
Figure 17.1d Scanner Voltage and Movement
Through rigorous quality control of its scanner piezos, Veeco has achieved excellent modeling of
scanner characteristics. Two calibration points are typically used for fine-tuning: at 150 and 440
volts. A third point is assumed at 0 nm/volts. These three points yield a second-order sensitivity
curve to ensure accurate measurements throughout a broad range of scanner movements.
Because scanner sensitivities vary according to how much voltage is applied to them, the reference
must be thoroughly scanned at a variety of sizes and angles. The user dictates, via the software, the
distance between known features on the reference’s surface and a parameter is recorded to
compensate the scanner’s movements. The X, Y and Z axes may be calibrated in any sequential
order; however, the linearization adjustments must be performed before any calibrations are
attempted (see
Section Note: ). Otherwise, calibrations will be undone by the linearity adjustments.
Note: Check the SPM’s measuring accuracy periodically to ensure that images are
dimensionally represented within acceptable limits of error. If measuring
accuracy is critical, or if environmental factors (e.g., humidity, temperature)
impact the SPM significantly, this may require a quick check at the start of each
imaging session. Establish a three-month service schedule for maintenance and
calibration.
Time
Scanner
Movement
Scanner
Voltage