Density of localized states in amorphous semiconductors

Abstract

A procedure is described for extracting the density of localized states of amorphous semiconductors from transient photo-current measurements. Based on a discretized multiple-trapping transport model, our deconvolution scheme determines, for each trap level, the time–temperature combination such that the activity is a maximum for that level. The density of the trap states is then obtained using linear-algebra techniques. As an example, our procedure is applied to computer-generated signals obtained using an exponential density of states. The deconvoluted distribution of levels is found to be in excellent agreement with the original one.