一种新型微机械热导压力敏感器及其数值模拟

A New Micromachined Thermal Conductivity Pressure Sensor and Its Numerical Modeling

本文研究了一种新型微机械ＣＭＯＳ热导压力敏感器。其压力测量范围是０．００１－１００Ｔｏｒｒ。整个量程范围内，多晶硅热敏电阻相对变化（即灵敏度）优於３０％。为使敏感器结构性能优化，我们首次开发了一软件包对器件热电性能进行数值模拟。三维模拟问题被简化为两个２－Ｄ模拟，并将由稳态能量平衡得到的方程组离散化用非线性Ｇａｕｓｓ－Ｓｅｉｄｅｌ算法迭代求解。器件灵敏度的模拟结果和实验值相吻合。文中还对温度分布进行了计算，对材料的热电常数和器件几何尺寸的影响做了分析。

A new micromachined CMOS thermal conductivity pressure sensor has been developed.The full measurement range is 0.001-100 Torr where the relative change of the polysilicon thermistor resistance ΔR / R0 (i. e. sensitivity) is higher than 30%.In order to optimize the structure and performance of the sensor, we have developed first a software package which gives the numerical modeling for the operation of the divices. The 3-dimensional simulation is reduced to two 2-dimensional ones. An iterative nonlinear Gauss-Seidel procedure is applied to solve the system of discrete equations resulting from steady state energy balance. The performance of actual devices is compared against the simulated operation and is found to be in good agreement. The temperature profiles are calculatd and the effects of material parameters and geometry of devices are demonstrated.