Influence of Radiation on the Luminescence of Silicon Nanocrystals Embedded into SiO2Film

Abstract

Influence ofγ-irradiation on light emission properties of silicon nanocrystals imbedded into SiO2film is investigated. It was shown that small doses ofγ-irradiation (103–105 rad) lead to enhancement of photoluminescence intensity in the nc-Si/SiO2samples. This effect was explained by radiation induced passivation of recombination active centers on the nanocrystals surface. High doses of irradiation (~107 rad) lead to the photoluminescence intensity decrease up to 2 times. Radiation treatment of silicon oxide films with embedded amorphous silicon inclusions resulted only in the decrease of the photoluminescence intensity within the whole range of doses (103–5 × 107 rad). Radiation defects resulting in partial quenching of photoluminescence are characterized with the distributed activation energy of annealing with the peak position at ~0.96 eV and the frequency factor 107 s−1. The nature of such defects and the mechanisms of their creation are discussed.