低迟滞MEMS电容式气压传感器设计

摘要

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 analyse temperature drift of sensor, its capacitance sensitivity, the heating power and the matching via hole size. Analysis results show that sensor capacitive temperature drift of the sensor is 0. 029 fF/K, capacitive sensitivity is 30 fF/kPa. Heating cavity air can make the cavity air pressure increase 20 hPa more over ± 0. 2 hPa than sensor hysteresis error. This lays the foundation for the design and the structure optimization of low hysteresis sensor.%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。