Design and simulation of dual-axis MEMS accelerometer

Abstract

Micro electro Mechanical systems (MEMS) are integrated electro-mechanical systems with microscale features. These devices are effective and low power consumers, making them one of the prospective technologies for use in a variety of industries and fields, including as the automotive, consumer, industrial, optical, robotic, biotechnology, medical engineering, and military sectors. MEMS accelerometer is one of the prominent inertial sensor allied in different applications.The proposed work is intended on design, modelling and simulation of a dual axis crab-legged suspension system. By using the SOI MUMPs fabrication process flow formulated by MEMSCAP Foundry a capacitive-based MEMS accelerometer is designed. Natural frequency, cross axis sensitivity, frequency response, and static capacitance analysis are the main design characteristics.Sensor is designed for a low frequency applicatons by assuming a natural frequency of 4KHz, he actual bandwidth vs sensitiviy is about 2KHz and 0.088um/g respectively. The measured stiffness along × and y are kx = 176.089 N/m ky = 176.089 N/m respectively.The proposed design of the capacities sensing comb drive structure is capable of producing linear change of the displacement for applied accelerations between 1 and 1000 g (1 g = 9.8 m/s2), over which the stress values exceed the tensile strength of the silicon material. By using stationary,frequency domain studies and electro-mechanics physics, the simulation is carried out in the COMSOL Multiphysics tool.