A study of packaging effects on the performances of MEMS for high-G accelerometer

In this work, finite element simulation has been applied in frequency-domain and time-domain analyses for a packaged accelerometer used in high-G environments. In order to understand the effect of the adhesive material, which is filled in the gap between the sensor chip and the package bulk, on the output signal of accelerometer, a simplified packaged structure has been adopted in this analysis. The results from simulations show that the Young's moduli of the seal adhesive has important influences on the mode shapes of the packaged accelerometer and a small Young's modulus will bring in strong distortion of output signal of accelerometer. As the Young's moduli increased, the waveform of accelerometer output signal became better after digital filtering. The simulations for a practical packaging structure defined in this work showed that the results were similar to the simulations for the simplified structure of accelerometer with packaging, and the simulation results from the simplified structure could serve as a basis for design of high-G accelerometer packaging to a certain degree.