Direct Simulation Analysis of Electromechanical Coupling and Joule Heating Effect of a MEMS SiC Piezoresistive Accelerometer

MEMS accelerometers have been used in various fields of life, and the design methods for MEMS accelerometers are mature nowadays. But in the design of piezoresistive accelerometers, the general method of structural mechanics simulation combined with circuit theoretical models inevitably involves parameter assumptions and simplification of electrical models, which will introduce calculation error. Therefore, in this paper, a direct numerical simulation method using COMSOL is carried out for a SiC MEMS piezoresistive accelerometer. The electromechanical coupling simulation of the sensor is realized by combining the structural mechanics simulation with the current domain simulation. At the same time, the circuit thermal effect is introduced into the simulation process to realize the coupled calculation of the temperature field. This simulation method can effectively avoid the errors caused by the theoretical model, and at the same time provide technical support for the development of the machine-electric-thermal field system coupled simulation.