一、引言固体表面功函数的测量是最早、最灵敏的表面物理研究的方法之一。测量功函数,可归纳为两大类方法:绝对方法——利用各种激发使样品产生热电子、光电子、场电子发射,根据发射电子流与激发场的关系求出样品的功函数;相对方法——通过测量样品和参考电极(其功函数为已知)之间的接触电势差,求出样品的相对功函数。后者主要有Kelvin探针和电子束阻挡势两种较常用的方法。尤其在观 I. INTRODUCTION Measurement of work function of solid surface is one of the earliest and most sensitive methods of surface physics research. Measurement work function, can be summarized into two categories: absolute method - using a variety of excitation samples to produce hot electrons, optoelectronics, field electron emission, according to the relationship between the emission electron flow and the excitation field to find the work function of the sample; relative method - Find the relative work function of the sample by measuring the contact potential difference between the sample and the reference electrode (whose work function is known). The latter mainly have Kelvin probe and electron beam blocking potential two more commonly used methods. Especially in view