Piezoelectric scanners for atomic force microscopes: design of lateral sensors, identification and control

This paper presents the identification and control of piezoelectric positioners used in atomic force microscopes (AFM) with the goal of improving probe positioning on the sample surface. A novel sensor was developed for this task and employed to infer a sixth order linear two input two output model of the piezo's lateral dynamics. The piezo model was used to design a controller for tracking reference signals common in AFM operation. The controller and sensor were shown to significantly improve the microscope's ability to position the probe on the sample's surface, enabling the AFM user to precisely scan areas on a surface based on images from previous scans.