Electroluminescence in porous silicon at a reverse bias voltage applied to the Schottky barrier

Abstract

A model of electroluminescence originating in a structure composed of a metal and porous silicon at a reverse bias voltage applied to the arising Schottky barrier is suggested. In this model, the avalanche multiplication of hot charge carriers and nonradiative Auger recombination in porous silicon are taken into account. It is ascertained that the difference in the systematic features of an increase in electron and hole currents due to generate nonequilibrium charge carriers, as a result of avalanche multiplication of hot electrons, brings about a superlinear increase in the radiative-recombination intensity as a current function. The radiative-recombination efficiency is lowered in the conditions of an avalanche breakdown as a result of an increase in the contribution of the Auger processes. It is shown that an increase in the concentration of nanocrystallites in porous silicon represents a way for increasing the electroluminescence efficiency in this material.