【摘要】 金属氧化物半导体(MOS)气敏传感器的稳定性是气敏器件实用化进程中最具有挑战性的因素。影响器件稳定性的主要因素包括颗粒尺寸、颈部宽度、微裂纹、电极、湿度和温度的变化。颗粒的长大和颗粒间颈部尺寸的变化降低了耗尽层对总电阻变化的贡献;微裂纹的加剧使器件的电阻发生漂移,并且为水蒸气、氧气和待测气体扩散到敏感膜内部提供便捷的通道;电极的退化影响电极与气敏材料之间的接触电阻Rc;温度和湿度的改变使气体的吸附、脱附、反应活性和电子迁移率等都发生变化,因而器件的稳定性得不到保证。在机理分析的基础上,分别介绍了提高器件稳定性的方法。更多还原

【Abstract】 Stability of metal-oxide-semiconductor(MOS) gas sensor is the most challenging factor in gas sensor′s practical application.It is found that the main factors responsible for the instability of device include the change of grain size,neck width,micro-cracks,electrode,humidity and temperature.Grain growth and change of neck width reduce the contribution of depletion layer to the whole resistance change;micro-cracks lead to resistance drift and provide short pathways for moisture,oxygen,and sensing gases diffuse more deeply to the films;deterioration of electrode affects the contact resistance Rc between electrode and gas sensing material;the variation of humidity and temperature changes gas adsorption,desorption,reactivity and electron mobility,so it results in poor stability.Based on the mechanism analysis,corresponding methods to improve stability have been introduced.更多还原