Analysis of PL spectrum shape of Si-based materials as a tool for determination of Si crystallites׳ distribution

This paper represents the analysis of the shape of photoluminescence spectra of Si-based nano-materials vs. energy of excitation light and temperature of measurements as a tool for the estimation of Si nanocrystallites׳ distribution. The samples fabricated by electrochemical etching (allowed different termination of Si nanocrystallites to be obtained) were used as modeling material. Bright emission at room temperature was observed for oxygen-terminated Si nanocrytallites, whereas hydrogen-terminated samples emit at low temperatures only. For most samples the photoluminescence spectrum was found to be complex, demonstrating competitive emission from Si crystallites and oxide defects. In latter case to separate the contribution of each recombination channel and to obtain information about crystallite distribution, low-temperature measurements of photoluminescence spectra under different excitation light energy were performed.