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用扫描隧道显微镜在Ｃｕ（１１１）Ａｕ和Ｐｔ（１１１）Ａｇ表面上对局域功函数进行了测量．在扫描的同时通过测量隧道电流对针尖样品间距离变化的响应，可以在得到扫描隧道显微镜（ＳＴＭ）图的同时得到功函数图．用这种方法，成功地观察到Ａｕ，Ａｇ覆盖层与Ｃｕ，Ｐｔ衬底间的功函数的差别．结果表明：Ａｕ覆盖层的功函数介于Ｃｕ（１１１）和Ａｕ（１１１）的功函数之间，这与其它方法的结果一致．在Ｐｔ（１１１）Ａｇ表面观察到了局域功函数随覆盖层厚度的变化．本工作表明：扫描隧道显微镜在研究功函数与表面结构的关系方面是十分有用的；用测量局域功函数的方法还可以区分表面不同种的物质
Local work functions were measured on a Cu (111) Au and Pt (111) Ag surface using a scanning tunneling microscope. By measuring the tunneling current response to changes in the distance between the needle tip samples while scanning, a work function map can be obtained while obtaining a scanning tunneling microscope (STM) pattern. In this way, the difference in work function between Au, Ag overlay and Cu, Pt substrate was successfully observed. The results show that the work function of Au coating is between that of Cu (111) and Au (111), which is consistent with the results of other methods. The variation of local work function with the thickness of the coating was observed on Pt (111) Ag surface. This work shows that the scanning tunneling microscope is very useful in the study of the relationship between work function and surface structure. The method of measuring local work function can also distinguish between different kinds of substances on the surface