Internal photoemission characteristics of metal–insulator–semiconductor structures at low electric fields in the insulator

Abstract

This article completes the presentation of a model of photoelectric phenomena taking place in metal–insulator–semiconductor (MIS) structures at low electric fields, which was introduced in Ref. [H. M. Przewlocki, J. Appl. Phys. 78, 2550 (1995)]. A solution and analysis of model’s equations is given for the general case of nonzero net photoelectric current (J≠0) in the external circuit. This solution allows calculation of the photocurrent–voltage characteristics of MIS structures illuminated with ultraviolet radiation of different wavelengths λ. To verify these results, experimental characteristics were taken and are shown in comparison with the calculated ones. Excellent agreement between calculated and experimental characteristics, obtained for a wide range of different MIS structures, strongly supports the validity of the model. Limits of applicability of this model are illustrated and discussed. The model finds applications in developing new, highly precise, photoelectric measurement methods of MIS structures. Principles of three such methods are outlined. One of these methods has already been fully verified and has been successfully used in a number of investigations, while the other two, are currently being verified and optimized.