Photoluminescence of Silicon Rich Oxide films with different silicon excess and nitrogen content

The effect of the nitrogen on the photoluminescence in silicon rich oxide films with different silicon excess and nitrogen content was studied. The materials were deposited by low pressure chemical vapor deposition (LPCVD) and nitrogen was introduced adding ammonia to the reactive gases. Some samples were annealed at 1100degC in nitrogen ambient. The films were characterized by Fourier transform infrared spectroscopy (FTIR) and photoluminescence (PL). The emission intensity depends on the silicon excess, nitrogen content and thermal annealing. For as deposited samples the emission intensity increases with the nitrogen concentration, and a slight wavelength shift is registered with respect to the nitrogen concentration. For films annealed, strong red emission with peak at ~720 nm was observed, and the PL emission increase as nitrogen content decrease. The emission intensity and position peak can be adjusted by thermal annealing, varying the nitrogen content and silicon excess