Photoluminescence study of an Er-doped Si-rich siOx film

We have studied photoluminescence (PL) from samples of Er-doped Si-rich silicon oxide (SRSO) annealed at 875°C for 1 h in N2, N2 +5% H2 (FG1), Ar+5% H2 (FG2), and O2, respectively, or subjected to double-step annealing processes. For the given film composition, the PL spectra of the samples annealed in N2, FG1, or FG2 are similar in shape but reveal small differences in the intensities of emission bands; while the spectra are qualitatively different in the case of oxidation. By combining the treatments of oxidation and annealing in FG1, the PL intensity of the SRSO matrix increases significantly; the emission from Si nanoclusters (Si-ncls) is also enhanced while the Er3+ 1.54 μm PL remains efficient. The effects of annealing gas ambients are discussed in terms of hydrogen passivation, Si oxynitridation and/or oxidation occurring in the film upon annealing and play different roles in the PL.