Fabrication, modeling and integration of a silicon technology force sensor in a piezoelectric micro-manipulator

A silicon technology sensor integrated in a micro-gripper is presented in this work. The force sensor consists of a monolithic silicon cantilever based structure. Forces applied on the cantilever are sensed by piezoresistive gauges in the clamping area and the resulting output voltage is measured by a Wheatstone bridge. Scaling of the proposed force sensor is done using analytical and numerical tools. The resulting force sensor enables the measurement of forces ranging from 1 to 600 mN with a resolution of 10 μN. Characterization of force sensors in the laboratory has confirmed the expected range of forces. The former sensor is next integrated in a piezoelectric micro-manipulator called micro-robot on chip (MOC). The aim of this integration is the measurement of handling forces during the manipulation of micro-samples in SEM and room conditions. Results from the characterization of silicon sensors show that a force range from 1 to 600 mN is measured. This range of forces can be adapted to the particular conditions of the MOC micro-manipulator.