Low Voltage Thermo-mechanically Driven Monolithic Microgripper with Piezoresistive Feedback

Pick-and-place of micro/nano sized objects means handling of very tiny and very different in properties objects having specific behavior. Besides formal requirements of assembly processes, the tools for controllable manipulation with these objects should not affect the examined micro/nano environment, i.e. should be “small and passive” in any sense. Despite of the recent progress, most available micro-grippers are still suffering of high voltage power supply required, short lifetime, low detection sensitivity and high price. Prototypes of a newly designed micro-gripper, having advantages over the existing analogues, have been developed, experimentally studied, and presented in this paper. The envisaged microgripper is of normally-closed type with thermomechanically driven actuator and piezoresistive arm-displacement feedback. The thermo actuator is placed between gripper’s arms and consists of double-folded highly-doped compliant silicon beam. As low average voltage vs. arm displacement value as 1V/μm, was experimentally measured.