High-speed Serial-kinematic Spm Scanner: Design and Drive Considerations

This paper describes the design of a flexure-guided, two-axis nanopositioner (scanner) driven by piezoelectric stack actuators. The scanner is specifically designed for high-speed scanning probe microscopy (SPM) applications, such as atomic force microscopy (AFM). A high-speed AFM scanner is an essential component for acquiring high-resolution, three-dimensional, time-lapse images of fast processes such as the rapid movement of cells and the diffusion of DNA molecules. A two-axis SPM scanner is proposed, where the slow and fast scanning axes are serially connected and flexure guided to minimize runout. The scanner’s achievable scan range is approximately 10 m×10 m. Finite element analysis is utilized to optimize the mechanical resonance frequencies of the scanner. Experimental results show a first major resonance in the slow and fast axis at 1.5 and 29 kHz, respectively. This paper also discusses the various tradeoffs between speed, range, electrical requirements, and scan trajectory design for high-speed nanopositioning.