A dual-stage nanopositioning approach to high-speed scanning probe microscopy

A novel positioning concept for high-speed scanning probe microscopy is presented in which a dual-stage nanopositioner is used for precise positioning over large areas at high speeds. The nanopositioner combines a low-bandwidth, large-range commercial scanner with a custom-designed high-speed scanner for short-range positioning. We present the mechanical design, finite element simulations and experimental characterization of the high-speed scanner, showing exceptionally clean dynamics, high linearity and large actuation bandwidth. The scanner is equipped with a magneto-resistive position sensing scheme that provides subnanometer resolution over a large bandwidth. Advanced model-based feedback controllers are designed according to a newly developed control design architecture with direct shaping of the closed-loop noise sensitivity and experimental results are presented in which the dual-stage system is used for high-speed imaging in a custom-built atomic force microscope.