一种航空配套微压传感器芯片设计及制备

Design and Fabrication of a Pressure Sensor Chip Applied in Aviation Field

针对航空领域微小压力测量需求,介绍了一种沟槽梁膜复合结构压力芯片的设计和制备方法。设计的压力芯片解决了传统硅压阻压力传感器灵敏度与线性度的固有矛盾,通过有限元分析可动膜片应力应变输出,并结合曲线拟合分析,提出了一种优化芯片可动膜片结构尺寸的设计方法。利用MEMS加工工艺,实现了沟槽梁膜双重应力集中结构压力芯片的制备。在量程0~1 psi范围内,传感器灵敏度30.9 mV/V/psi,非线性误差0.25%FS,综合精度0.34%FS,实现了灵敏度和线性度的同步提高,满足了飞行器高度、风洞测试等领域的微压测试需求。

According to the micro pressure requirement from the aviation field,this paper presents a design and fabrication method for a complex structural pressure sensor chip with grooved membrane combined with beam.The proposed sensor chip can alleviate the contradiction between sensitivity and linearity for a traditional silicon piezoresistive pressure sensor.The stress and deflection of the membrane are calculated by the finite element method(FEM).By the combination of the curve fitting analysis,an optimization method of the sensitive membrane is introduced.Finally,the sensor chip with the proposed structure is fabricated by the MEMS technology.The results show that the sensor has obtained a sensitivity of 30.9 mV/V/psi,a nonlinearity error of 0.25%FS and an integrated accuracy of 0.34%FS in the range of 0~1 psi,realizing the synchronous improvements for the sensitivity and linearity,which meets the requirement in the measurements of aircraft height and wind tunnel.