Time-resolved photoluminescence in amorphous silicon dioxide

TLDR

Time‑resolved photoluminescence of bulk amorphous SiO₂ was measured at 7.9‑ and 6.4‑eV excitation, at room temperature and 25 K, with intensity and decay rates recorded for various bands, and similar measurements were performed on crystalline quartz and a thermally grown oxide. The spectra revealed distinct bands at 1.9, 2.2, 2.7, and 4.3 eV, a very broad band peaking between 3–4 eV extending below 1.5 eV, with the 4.3‑ and 1.9‑eV bands present in the thermal oxide but the 2.7‑eV band absent, and the 1.9‑eV band absent in crystalline quartz.

Abstract

We report time-resolved measurements of photoluminescence in bulk a-${\mathrm{SiO}}_{2}$ using 7.9- and 6.4-eV excitation. Time-resolved spectra have been obtained at room temperature and 25 K, and the intensity and decay rates of various luminescence bands have been measured as a function of temperature. Bands at 1.9, 2.2, 2.7, and 4.3 eV are identified. In addition, there is a very broad luminescence peaking between 3--4 eV but extending to below the 1.5-eV cutoff of our measurements. We have also measured photoluminescence in crystalline quartz and in a thermally grown oxide. Both the 4.3- and 1.9-eV bands are seen in the thermal oxide, but the 2.7-eV band is absent. In the crystal, the 1.9-eV band is absent.