ZnO/SnO_2,SnO_2/ZnO UPF复合膜的制备及气敏特性研究

PREPARATION AND GAS-SENSING PROPERTIES OF ZnO/SnO_2, SnO_2/ZnO BILAYER THIN FILMS

用直流气体放电活化反应蒸发沉积技术在普通玻璃基片上制备了ZnO／SnO2及SnO2／ZnO超微粒子（UPF）双层复合薄膜。样品经扫描电子显微镜（SEM）和X射线衍射仪分析，结论为超微粒子的复合薄膜。同时提出了最佳制备工艺。气敏测试结果表明：ZnO／SnO2及SnO2／ZnOUPF复合膜较单层ZnO及SnO2UPF表现出优良的选择性，其灵敏度和最佳工作温度也得到相应的改善。

In this paper, a dc gas discharge activating reaction evaporation technique was used to prepare ZnO/SnO2 and SnO2/ZnO UPF bilayer thin films. These bilayer thin films of ultrafine particles were grown successfully onto ordinary glass substrates. The films have been characterized by means of XRD and SEM,and shown to be the UPF. Their properties of gas-sensing were investigated. We have obtained the best technical conditions. The result of gas-sensing experiment shows that ZnO/SnO, and SnO2/ZnO UPF bilayer thin films have a good selectivity for detecting C2H5OH in the presence of gasoline gas and (CH3)2 CO gas, an increase of sensitivity, and a decrease of operating temperature. The bilayer UPF thin films prepared by this procedure may serve as high-quality gas sensors.