应用SU-8粘合技术的微型压力、温度和湿度集成传感器

摘要

The integrated pressure, temperature, and relative humidity sensors with high precision are highly needed in environmental monitoring and industrial control,for they have the superiorities on small sizes, low weights, low costs and easy to produce. Based on MEMS technology, a novel high precision integrated pressure, temperature, and relative humidity sensor is developed and its design principle and composition are introduced. Then,the fabrication process sequence and experiments for the integrated sensor are given. The 5.5 mm×3.5 mm×0.8 mm sensor chip consists of a piezoresistive Pt pressure sensor using adhesive bonding with SU-8, a Pt resistance temperature sensor and a capacitive humidity sensor.Experiments show that the pressure sensor has a linearity of 0.2%and a precision of 0.05% in square fitting;the temperature sensor has a precision of 0.3% and the humidity sensor shows the wide ranges of sensing ambient relative humidity from 25%RH to 95%RH and a linear correlation coefficient of 0.998 in 28.5 ℃. The high precisions of three sensors indicate the compatibility of the fabrication of this integrated sensor.%压力、温度和湿度集成传感器具有体积小、成本低和可批量生产等优点,在环境监测和工业控制等领域应用广泛.基于微机电系统(MEMS)技术,本文设计和制作了一种尺寸为5.5 mm×3.5 mm×0.8 mm的高精度压力、温度和湿度集成传感器.该集成传感器由SU-8真空粘合技术制作的铂压阻压力传感器,铂电阻温度传感器和电容式湿度传感器组成.介绍了该集成传感器的设计思想、结构和制备过程,给出了实验和测试方法.结果表明,压力传感器的精度优于0.05%;温度传感器的精度为0.3%;湿度集成传感器的量程为25%RH～95%RH,其性能曲线的线性相关系数为0.998.集成传感器中的这3种传感器的高精度表明该集成传感器的制作工艺具有良好的工艺兼容性.