Liquid packaging effects on piezoresistive MEMS accelerometer

MEMS (Micro-electro Mechanical Systems) accelerometers are wildly used in vibration and impact detecting. Piezoresistive accelerometer is one of the wildly used types of sensor on the market with normal air package. However, when it is used in high impact environment, its fragile sensitive parts might get damaged. In this paper, we tried to use non-conducting liquid instead of air to fill the package shell of piezoresistive accelerometer. Its sensitivity and measuring range were analyzed when the package shell was filled with glycerinum, cyclohexane and silicon oil, respectively. Its resonant frequencies with glycerinum, cyclohexane and silicon oil package were also analyzed. The conclusion is that the liquid package is more suitable than air package for the piezoresistive MEMS accelerometer in harsh environment.