Photoluminescence analysis of plasma-deposited oxygen-rich silicon oxynitride films

Photoluminescence spectra were observed for hydrogenated oxygen-rich silico n oxynitride films with different N/O ratios, deposited by plasma-enhanced chemical vapor deposition. In the sample with a small ratio of N/O, two lum inescence bands at 4.4 and 2.7 eV originated from silicon homobonds in SiO2 were observed, while a luminescence band at 2.6-2.9 eV which has very simi lar properties to the one observed in SiNx was observed in the sample with a large ratio of N/O. The results of Fourier-transform infrared spectroscop y, electron spin resonance, X-ray photoelectron spectroscopy and scanning e lectron microscopy indicated that the luminescence band at 2.6-2.9 eV resul ts from Si-N bonds in the films and that the present films have regions whe re SiN bonds gathered.