Design of an SOI-MEMS high resolution capacitive type single axis accelerometer

Abstract

In recent years, high resolution micro accelerometers are increasingly finding various applications in different segments of life. The current work deals with the design of a high resolution single axis accelerometer based on SOI-MEMS technology. Accordingly two different approaches for designing comb type, capacitive, SOI-MEMS accelerometer is presented. Initially a system level approach using a simulation platform from SABER is carried out to obtain the basic design. Later, a device level design is carried out by building three dimensional (3D) geometric models using finite element (FE) simulations through CoventorWare software. Different design parameters like mechanical and electrical sensitivity, capacitance values, resonant frequency, etc. are obtained in either of the cases and compared. The design is optimized based on the overall sensitivity and the system noise level both electrical and mechanical, respectively. The complete design is worked out in accordance with the silicon on insulator based multiuser MEMS fabrication processes (MUMPs) technology from MEMSCAP foundry.