QUANTITATIVE SURFACE PHOTOVOLTAGE SPECTROSCOPY OF SEMICONDUCTOR INTERFACES

A comprehensive and quantitative method for extracting the important p arameters of interface states is presented. The method is based on wav elength-, intensity-, and time-resolved surface photovoltage spectrosc opy, as well as on measurements as a function of the thickness of an o verlayer. Data analysis provides detailed information about interface state properties, including their energy position and distribution, de nsity, and the transition probabilities, i.e. their thermal and optica l cross sections. It is also possible to distinguish between surface a nd bulk states, and determine the spatial site of the states in the ca se of a heterostructure. Experimental examples for various III-V and I I-VI compound semiconductors are given.