Research on the Stress Optimization of the MEMS Gyroscope with Isolation Structure

The thermal stress becomes one of the main factors to limit the improvement of the MEMS gyroscope’s performance. This paper proposes a stress-isolated structure with a santilevered slab based on the high-precision MEMS butterfly gyroscope to reduce the thermal stress. The effect of the thermal stress is analyzed theoretically, and the stress- isolated structure is deisgned. In order to improve the effect of the stress isolation and comprehensive performance of the gyroscope, the critical sizes of the stress-isolated structure are optimized through simulation. Simulation results show that the thermal stress is reduced by about 346 times after stress isolation. The drift of the gyroscopes’ driving frequency are also tested in the environment of the variable temperature before and after stress isolation. Results show that the frequency varation is reduced by 28.6% after integrating the stress-isolated structure, which further demonstates the effect of the stress optimization.