A three-axial micro-force sensor based on MEMS technology

This paper presents the design, fabrication and characterization of a MEMS three-axial micro-force probe sensor for dimensional metrology of micro object in microcosmic field and micro-force measurement in the field of bio-medical and robot finger. Through analysis of the stress distribution of the sensor by theoretical and ANSYS software, a model of the structure is established and the piezoresistors are doped on the end of the beam to get high sensitivity. The optical fibre probe is design to be ladder structure. The die size of the sensor is 4 × 4 × 5.9 mm³, and it is fabricated by MEMS technology. Preliminary characterization tests have been performed by means of an experimental test bench, the experiment results indicate that the sensor can test three-axial micro-force in μN scale, and the resolution is up to 3 μN.