多孔硅气体传感器的制备及其气敏性能的研究

Study on Fabrication of Porous Silicon Gas Sensor and Gas Sensing-characteristics

以P＋型硅片为基底,利用双槽电化学腐蚀方法制备不同孔隙率的多孔硅（Porous Silicon）,介绍多孔硅气体传感器的原理和优点,通过SEM和AFM对PS薄膜的表面形貌进行分析,研究不同孔隙率条件下PS薄膜的气敏灵敏特性。结果表明：随着孔隙率的增加,PS薄膜的响应/恢复时间不断减小,薄膜对空气中较低浓度的NO2（体积分数为0.1×10^-5 - 6×10^-5）具有优异的敏感特性和响应特性。

Double-cell electrochemical etching was used to prepare PS based on P＋ type and the princi- ple and advantages of porous silicon gas sensor were presented. The film morphology was character- ized by SEM and AFM. The sensing-characteristic of PS films was studied in terms of different of po- rosities. The results show that the response/recovery time of PS thin films decreases with increasing the current density and the PS thin film reveals excellent sensitivity and response characteristics in the presence of low concentration of 0.1×10^-5 - 6×10^-5 NO2 gas in air.