低电压气体导电及高速高灵敏度湿敏传感器研究

Study of Gaseous Electrical Conductance with Low Working Voltage and Fast Response High-Sensitivity Humidity Sensor

气体在电场作用下可形成导电能力。研究发现气体中微量水汽的存在对此导电能力具有极为灵敏的作用。本文阐述了低电压气体导电机理及其敏感效应。研制了一种低电压微功耗微型电极系统实现自持暗放电，使通常气体导电必需的高电压降低了一个多数量级，仅为几百伏。基于低电压气体导电机理的湿敏传感器的水汽分压强灵敏度优于１Ｐａ／ｎＡ，反应时间优于一秒。上述结果表明：气体低湿度快速测量是实际可能的。

Electrical conductance of gases can be formed by electrical field. We have found that the existance of moisture in gases strongly acts on the electrical conductance of the gases. The working mechanism of the electrical conductance with low working voltage and micropower comsumption and humi-sensing effect of the electrical conductance are discribed. A special electrode system, in which a self-sustaining dark electrical discharge is formed with only several hundred volts about tens times lower than that of normal electrode system, has been studied and developed. The moisture sensor based on the gaseous electrical conductance is then developed. Its humidity sensitivity in vapour partial pressure is better than 1 Pa/nA, and its response time is less than 1 second. It could be concluded that fast detection of the moisture with tiny content in gases is put into practice.