Surface Analysisi under Air by UV Photoelectron Yield Spectroscopy

紫外光电子产额谱(UPYS)是研究空气气氛下固体样品表面性质的一种新工具。本文通过对半导体和表面修饰金的UPY谱的测量和分析，阐明了该技术在空气中作为表面分析技术的能力。从UPY谱确定了不同类型硅片的光电子阈值能Et。Et和光电子产额Y反映了表面电子能带结构的性质，并且对杂质的类型和浓度很敏感。利用UPY谱的导数可以很容易地区分硅片的(111)面和(100)面。通过测量烷基硫醇修饰的金金属的UPY谱，确定了每个低能电子在碳氢层中的逃逸深度约为11A。该值可比或小于XPS中所测得的光电子值，表明UPYS对样品表面非常敏感。功能修饰金的Et反映了表面官能团的偶极幅度及其取向。

Ultraviolet photoelectron Yield spectroscopy (UPYS) is a new tool to investigate the surface property of the solid sampke under air atmosphere. In this study, the UPY spectra of semiconducters and surface modified gold metal were measured and andlyzed to elucidate the ability of this techniquw as surface analytical technique in air.The photoelectron threshold energy, Et of the various types of silicon wafers were determined form the UPY spectra. The Et and photoelectron Yield, Y reflect the nature of the surface electronic band structre and are sensitive to the type of the inpurity and its concentration. It is also indicated that the (111) and (100) faces of the silicon wafers can be easily distinguished by the use of derivative of th eUPY spectra.The escape depth of th every low energy electrons in hydrocarbon layr was determined to be about 11A by measuring the UPY spectra of alkane thiol modified gold metals. This value is vomparable or smaller than that for photoelectron neasured in XPS, indicating that the UPYS is very sensitive to the suface of the sample. The Et for the functinally modified gold metal reflects the dipole amplitude and its orientation of the surface functional group.