Structural Design and Optimization of MEMS Gas Sensor Microhotplate

The gas sensor microhotplate, as a key component of the gas sensor, is of great significance for improving the energy utilization and gas-sensitive performance of the gas sensor. The MEMS gas sensor microhotplate designed in this paper adopts the suspended-film structure, proposes novel shapes of electrode, and applies finite element technology to conduct multi-physical field coupling modeling and simulation, and compares and analyzes the temperature and stress distributions as well as the power consumption of each plan, and selects the optimal plan for the structural optimization work. Finally, based on the established model of the microhotplate, an optimization model is built by using COMSOL. After optimization, the temperature gradient of the microhotplate is reduced from 15.6% to 6.6%, and only 9.14 mW is needed to reach 390°C, which achieves the improvement of the heating performance of the MEMS gas sensor microhotplate.