湿度和频率对湿敏元件电学特性的影响

Effects of Humidity and Frequency on Electrical Properties of Humidity Sensor

在印有梳状电极的石英玻璃表面涂覆氧化钛纳米薄膜制备湿敏元件,研究不同湿度、不同频率下的电学特性。结果表明,随着湿度的增大,湿敏元件的电阻值、阻抗值减小,电容增大;当湿度一定时,电阻值、电容值都随频率的增大而减小;工作频率为0.01 kHz、相对湿度高于40%时,具有较好的湿敏特性。实验说明湿敏元件中不仅电子、离子浓度发生变化,材料的极化也发生了变化。

Titania films were prepared on the quartz glass whose surface was printed with comb-like Ag electrode and humidity sensor was constructed. The electrical properties of the sensor were analyzed on different humidity and frequency. Experimental results show that, with relative humidity increasing, the resistance and impedance of the humidity sensor decrease but the capacitor increases when relative humidity is fixed both the resistance and the capacitor decrease as the frequency increases. The humidity sensing properties are good in the relative humidity higher than 40% and test frequency is 0.01 kHz. The concentration of electron and ion changes with relative humidity, the polarization of the thin film also changes.