钛合金纳米薄膜压力传感器非线性及灵敏度研究

Study for the nonlinearity and sensitivity of the titanium alloy nano film pressure sensor

为了满足钛合金纳米薄膜压力传感器高精度测量要求,基于薄膜厚度、凸岛、电阻形状和排列位置对传感器非线性、灵敏度的影响分析,设计并优化了以钛合金薄膜为敏感元件的两种量程的压力传感器。结果表明,有无凸岛,传感器的最大应力均出现在膜片边缘处。增加凸岛后,最大应力降低,位置基本保持不变。增加凸岛或随着凸岛直径增大,非线性降低,灵敏度相应增加。理论上,为了保证传感器灵敏度不小于2.5 mV/V,2 MPa量程时,增加Φ2 mm凸岛后,非线性降低至0.05%,灵敏度约为2.67 mV/V。4 MPa量程时,增加Φ3 mm凸岛后,非线性降低至0.02%,灵敏度约为2.89 mV/V。制备了两种量程传感器并测试分析,2 MPa量程时,其灵敏度及非线性与理论值最大偏差分别为0.01 mV/V及0.01%。4 MPa量程时,其灵敏度及非线性与理论值最大偏差分别为0.16 mV/V及0.02%。本研究为钛合金纳米薄膜压力传感器关键参数设计提供重要依据。

In order to meet the high-precision measurement requirements of titanium alloy nanofilm pressure sensors,based on the influences of thin film thickness,convex islands,resistance shape and arrangement position to the nonlinearity and sensitivity of sensors,two range pressure sensors are designed and optimized using titanium alloy thin films as sensitive elements.The results indicate that whether there are convex islands or not,the maximum stress of the sensor occurs at the edge of the diaphragm.The maximum stress decreases and the position remains basically unchanged after adding convex islands.Adding convex islands or as the diameter of the convex island increases,the nonlinearity decreases and the sensitivity increases accordingly.To ensure that the sensitivity is not less than 2.5 mV/V in theory,2 MPa sensor increasing convex islands withΦ2 mm,the nonlinearity decreases to 0.05%and the sensitivity is about 2.67 mV/V.4 MPa sensor increasing convex islands withΦ3 mm,the nonlinearity decreases to 0.02%and the sensitivity is about 2.89 mV/V.Two ranges of sensors are prepared and tested,the results show that at a range of 2 MPa,the maximum deviations of the sensitivity and nonlinearity between actual values and theoretical values are 0.01 mV/V and 0.01%,respectively.At a range of 4 MPa,the maximum deviations of the sensitivity and nonlinearity between actual values and theoretical values are 0.16 mV/V and 0.02%,respectively.This study provides an important basis for the design of titanium alloy thin film pressure sensors.