A new concept was suggested to explain the effect of dislocations on electroluminescence in Si diodes. This concept was based on consideration of the spatial correlation between injected electrons and holes that recombine inside a dislocation core. This correlation leads to an increase in the probability of radiative recombination for electron–hole pairs. Two cases were analyzed. In the first case, the resulting current was controlled mainly by tunneling of electrons and holes along dislocations, which was followed by electron–hole recombination under the conditions of barrier lowering. In this situation, electroluminescence was not related to the fundamental absorption edge and the energy position of the electroluminescence band shifts to shorter wavelengths as either the temperature decreased or the applied voltage increased. In the second case, the diffusion-related component was prevalent in the total current. The radiative recombination of electron–hole pairs occurred in quasi-neutral regions and the electroluminescence exhibited an edge-related character. It was shown that the suggested mechanism may be responsible for a substantial enhancement of both the electroluminescence intensity and the quantum efficiency in Si diodes with dislocations if the Shockley–Read–Hall lifetime was shorter than 10–3 s.

A Mechanism of Electroluminescence in Silicon Diodes with a High Dislocation Density. A.V.Sachenko, Y.V.Kryuchenko: Semiconductors, 2005, 39[9], 1096-101