高性能MEMS电容压力传感器的设计及其热分析

为了进一步提高接触式电容压力传感器的性能,设计了一种高性能双凹槽结构的接触式电容压力传感器,并对该传感器在高温环境中的总体性能进行了分析。推导了热传导和热弹性理论,并对影响传感器热分析的各个因素与温度的依赖关系进行了描述;在整个分析过程中,使用ANSYS软件并结合有限元方法对全尺寸传感器的热效应进行模拟。结果表明,在接触工作状态双凹槽接触式电容压力传感器的温度对输入(压力)-输出(电容)特性的影响是线性的,且线性范围内初始压力随温度的升高而降低;当温度载荷为550 K时,双凹槽结构的灵敏度为1.21×10-6pF/Pa,比传统单凹槽的0.8×10-6pF/Pa高出50%,表明该压力传感器有着非常优异的高温特性。

Design and thermal analysis of high performance MEMS capacitive pressure sensor

To improve the high temperature properties of touch mode capacitive pressure sensors, a Double-cave Touch Mode Capacitive Pressure Sensor (DTMCPS) is proposed and its overall performance in high temperature environment is analyzed significantly. Firstly, the theories of heat transfer and thermo-elasticity are deduced, and effects of many temperature dependence factors on thermal analysis of this sensor are described. Then, Finite Element Method and ANSYS software are used to simulate the thermal effect of the full dimension sensor during this analysis. The results indicate that the influence of temperature on the input (pressure load) and output (capacitance) characteristics is linear in a touch operation state of this DTMCPS, and its initial pressure of linear range reduces with temperature increasing. Furthermore, the sensitivity of double-cave structure sensor is 1.21×10-6 pF/Pa at 550 K, which has been 50% up on 0.8×10-6 pF/Pa of the traditional single-cave structure. These results show that this sensor has excellent high-temperature performance.