Simulation on the encapsulation effect of the high-g shock MEMS accelerometer

The modal and the response during acceleration of high-g shock MEMS accelerometer were simulated using finite element method based on a practical packaging model. The modal frequency of the packaging structure increases with the Young´s modulus of encapsulation resin. But the modal-frequency may be smaller then that of the packaging structure without encapsulation if the encapsulation resin is very soft. Under the 100 kG acceleration (1 G = 9.8 m/s/sup 2/), the simulated output voltage of accelerometer decreases slowly with the increase of Young´s modulus or density of encapsulation resin. The simulated output voltages are close to the analytic results. They are also linear with the environmental accelerations.