Efficient excitation transfer in silicon studied by Fourier transform photoluminescence excitation spectroscopy

Abstract

Direct experimental evidence of excitation transfer in the recombination via deep defects in silicon is provided, by a novel approach of Fourier transform photoluminescence excitation spectroscopy. The 735 meV iron-related defect in Si is used as a model case. It is shown that this defect can be excited via two deep states of other centers that give rise to broad lines in the excitation spectrum at 976.3 and 1115.6 meV. The linewidths of these features infer extremely efficient transfer processes. Such an efficient excitation transfer is expected to play an important role in excitation and recombination processes in silicon.