Luminescent and Raman study of nanostruc-tures formed upon annealing of SiOx:Sm films

Abstract

ncs-Si–SiO x :Sm structures formed by high-temperature air annealing of the SiO x films doped with samarium during thermal co-evaporation in vacuum of silicon monoxide and metallic Sm was studied. By measuring the spectra of photoluminescence (PL), it has been shown that doping of SiO x films with Sm stimulates their decomposition into Si and SiO 2 , and also reduces the transition temperature of silicon nanoparticle from the amorphous state to the crystalline one. With an increase in the impurity content up to 2 wt.%, along with the ncs-Si luminescence, the PL spectrum exhibits emission bands of Sm 3+ and Sm 2+ ions, which do not appear at a lower Sm concentration. The presence of silicon nanocrystals in SiO x films doped with Sm and annealed at 970 °C in air has been confirmed using Raman scattering spectra. A possible mechanism for interaction of samarium ions with the SiO x matrix and ncs-Si has been discussed.