Design analysis of polysilicon piezoresistors PDMS (Polydimethylsiloxane) microcantilever based MEMS Force sensor

This study is aimed for the analysis of different designs for sensing low magnitude forces which lies in the micro-Newton range and suitable for biomimetic microbotics. For this, a flexible and high sensitive Micro Electro Mechanical System (MEMS) based Force sensor using piezoresistive sensing mechanism has been analyzed. Design analysis is carried out for sensitivity enhancement on microcantilever by incorporating various combinations of stress concentrated regions (SCR) and their respective arrays. The materials under consideration for sensor are polysilicon piezoresistors and Polydimethylsiloxane (PDMS) microcantilever. For design analysis, the designing and simulation work is assessed using Finite Element Analysis approach in COMSOL Multiphysics 5.3a software. The results revealed that the electrical sensitivity of 1.62 mV/mu N within (0-100) mu N operating range is achieved for microcantilever with rectangular SCR with square SCR array. This operating range has many applications in microbotic field such as sensing tactile movements. Hence, MEMS Force sensor for low magnitude forces has been designed with high sensitivity and flexibility.