In situ testing and calibration of tube piezoelectric scanners

Abstract

The tube scanner, a piezoelectric ceramic tube with the outer metal coating sectioned into four quadrants, is widely used in scanning probe microscopes. Based on stress-and-strain analysis, we obtain analytic expressions for the deflections of tube scanners, which are found to be in good agreement with the results of finite-element analyses and experimental measurements. Also, we show that by applying an AC voltage on one of the quadrants, an AC current of well-defined intensity and phase is generated from each of the other three quadrants to the ground (inner metal coating). This current can be used to measure the piezoelectric coefficient and to inspect the uniformity and geometrical accuracy of tube scanners. A combination of those who results provides an easy and accurate method for testing and calibrating tube scanners in situ, for example, in a vacuum chamber or in a cryostat. © 1992.