Visible photoluminescence from the annealed TEOS SiO2

We report the visible photoluminescence (PL) excited by Ar-ion laser (514.5 nm) at room temperature from the TEOS SiO2 films annealed under the protection of flowing N2. It was found that the PL peak position located at between 610 and 640 nm does not significantly change with the annealing temperature (Tanneal). The PL intensity of TEOS SiO2 films first exhibits a gradual increase as Tanneal is below 850 °C; thereafter it keeps almost constant when 850 °C < Tanneal < 1150 °C; finally, it shows a strong increase when Tanneal is increased up to 1200 °C. The results of Raman scattering, Fourier-Transform infrared absorption and X-ray photoelectron spectra indicate that the PL mechanism in TEOS SiO2 films should be attributed to the defect emission at the surface of the SiO2 film.