Defect related photoluminescence in Si wires

Photoluminescence spectra and their dependence on the temperature have been used to study the peculiarities of the red photoluminescence in low-dimensional Si structures, such as porous silicon and silicon oxide films with an admixture of silicon. It has been shown that red photoluminescence band of Si wires is complex and can be decomposed into two elementary bands. Practically the same positions of photoluminescence bands are observed in silicon oxide films. Comparative investigation of photoluminescence temperature dependence in Si wires and silicon oxide indicates that oxide defect related mechanisms for photoluminescence bands are involved. The photoluminescence excitation mechanisms in both objects are discussed as well.