硅压阻式湿度传感器的研究

Study of the Piezoresistive Humidity Sensor

本文研究了一种利用压阻原理检测相对湿度的传感器结构。改进了压阻结构,在压阻的拐弯处用Al引线代替浓硼掺杂,避免了拐弯处压阻的负压阻效应,提高了传感器的灵敏度。采用离子注入工艺制作压阻,使得硼掺杂更加均匀,提高了压阻的匹配度。对流水出来的传感器进行测试和分析,数据结果表明:在20℃时,传感器的灵敏度为0.236 mV/%RH,最大湿滞约为5%RH,传感器有较好的线性。

A humidity sensor which uses piezoresistive effect to detect the relative humidity was studied.Metal Al was used instead of heavy boron-doped layer to avoid negative piezoresistive effect at the turning of the piezoresistor.Ion implantation was used for fabricating the piezoresistor in order to obtain uniform B-doping and make the piezoresistors match better.The sensor was tested,the results show that the sensitivity of the sensor is 0.236 mV/%RH.The largest hysteresis is about 5%RH,the sensor also has good linearity.