A micromachined 2DOF nanopositioner with integrated capacitive displacement sensor

This paper presents the design, fabrication and characterization of a micromachined two degrees-of-freedom (2DOF) nanopositioner. The proposed micro-electro-mechanical system (MEMS) stage, consisting of comb-drive actuators and on-chip capacitive displacement sensors in both X and Y directions, can simultaneously actuate the microstage and sense the corresponding displacements. A commercial capacitive readout IC (MS3110) is used for the open-loop capacitive sensing. The first resonance frequency of the stage is measured to be 4.24 kHz. The positioner has a dynamic range from −6.27 µm to +6.64 µm at an actuation voltage of 100 V