低迟滞MEMS电容式气压传感器设计

针对传感器的机械迟滞问题,提出一种减小迟滞偏移的方法,设计了低迟滞误差的电容式气压传感器。使用ANSYS和FLUENT软件模拟电容式传感器的工作性能,分析传感器的温漂特性、电容灵敏度及加热功率与通孔大小的匹配问题。分析结果表明传感器的电容温漂为0.029 fF/K,电容灵敏度为30 fF/hPa;加热空腔气体可以驱动空腔内气压增加20 hPa,超过传感器的迟滞误差范围,为低迟滞误差传感器的设计和结构优化提供了依据。

Design of Low Hysteresis Capacitive Pressure Sensor Based on MEMS

For the problem of mechanical hysteresis , a method of reducing hysteresis offset is presented and a low hysteresis capacitive pressure sensor is designed . The sensor working performance is simulated with ANSYS and FLUENT software to analysis sensor temperature drift , capacitance sensitivity , the matching of heating power and the via hole size . Analysis results show that sensor capacitive temperature drift is 0.029 fF/K, capacitive sensitivity is 30 fF/hPa. Heating cavity air can make the cavity air pressure increasing 20 hPa more over ±0.2 hPa that sensor hysteresis error is . This lays the foundation for the design and the structure optimization of low hysteresis sensor .