Design optimization in SOI-based high sensitivity piezoresistive cantilever devices

In this work, the authors present the new design of MEMS high-sensitivity piezoresistive cantilever. The prospect is to develop the tactile sensor for space mission. The finite element method with parametric design, carried out using CoventorWare2008, was applied to obtain the most advantageous performance by optimizing shape and geometrical dimension of both cantilever and piezoresistor. The sensor performance was measured on the basis of output voltage and surface stress sensitivity. Frequency and temperature studies were investigated. An analysis was also conducted on the effects of incorporating various stress concentration region designs at the cantilever. Results show that cantilever with “appropriate” shape and structural holes yields maximum stress which results in maximum sensitivity. A comparison between different devices in terms of dimension and shape: cantilever, piezoresistor, holes are presented.