采用磁控溅射法在预镀ZnO掺Al薄膜的玻璃基片上制备了银纳米薄膜。研究了Ag纳米薄膜暴露在室温大气条件下连续60d的氧化现象、过程和机理。用光学显微镜、原子力显微镜、X射线光电子能谱仪、紫外–可见光谱仪和四探针电阻测试仪对薄膜的形貌、成分和性能进行了表征。结果表明Ag纳米薄膜在室温大气中易被氧化而失去其优异光电性能的机理是:首先是大气中的O2化学吸附在薄膜表面,引起表面重构;然后含S的小分子气体(如:H2S,SO2)化学吸附在薄膜表面,引起表面重构;最后Ag纳米薄膜在O2和含S的小分子气体作用下被氧化成大量圆锥形柱状的Ag2S和少量的Ag2SO4;大气中的CO2和N2不会与Ag纳米薄膜反应。
Silver thin films were deposited on the aluminum-doped zinc oxide-coated soda-lime glass substrates by radio fi'equency magnetron sputtering method. The oxidation phenomena, process and mechanism of the silver thin films under room temperature and atmospheric environment were investigated for 60 d. The morphology, composition and properties of the films were characterized by optical microscope, atomic force microscope, X-ray photoelectron spectroscope, ultraviolet visible spectrometry, and four-probe method. The results show that the mechanism of oxidation of silver thin film exposed to room temperature and atmospheric environment is as follows: O2 is firstly chemical adsorbed on the surface of the films and the surface reconstruction is caused. Then small molecule gases containing S, such as H2S and SO2, are also chemical adsorbed on the surface of the films and the surface reconstruction is caused again. Finally, the silver thin films are oxidized to a great deal of columnar Ag2S and a little Ag2SO4 by O2 and small molecule gases containing S. The silver thin films are not oxidized by CO2 and N2 in the air.