Simulation of Time Decay for Photoluminescence Emitted from Silicon Crystals Excited by Short Laser Pulse

Abstract

The time decay for photoluminescence (PL) emitted from silicon crystals excited by a short laser pulse has been simulated for the first time on the basis of two simplified approximations in order to obtain both bulk carrier lifetime (τ_b) and surface recombination velocity (S). One approximation is that the PL intensity is proportional to the normalized (averaged) excess carrier densities, whereas the other is that it is proportional to the recombination rate. We compared simulated results with experimental ones and obtained better coincidence in the case of the latter rather than the former approximation, which means that the Buczkowski et al.'s algorithm for obtaining both τ_b and S [J. Appl. Phys. 69 (1991) 6495] cannot be applied to the PL decay method. Therefore, a new algorithm has been developed in this present work.