A High G Accelerometer Based on SOI Piezoresistive Material With Cantilever Beam

A high g accelerometer based on Silicon-On-Insulator (SOI) piezoresistive material with cantilever beam is described, which can measure the acceleration up to 10⁵ g. The excellent electrical and mechanical properties of SOI material may be suitable in the applications of the high-g force accelerometer as an electromechanical sensor. One kind of SOI Wheatstone bridge strain silicon gauge is developed, and the size of the SOI silicon gauge is 1.8mm×1.6mm×0.2mm. A kind of cantilever beam structure is designed to endure the impact of high-g acceleration. The SOI silicon gauge is bonded on the cantilever beam by the way of AuSn eutectic. The fabricated devices have been subjected to shock tests up to 10⁵ g by using a Hopkinson’s bar, the resonance frequency of which may be up to 40 kHz. The design modeling procedures and results are reported and the fabrication steps are described.