Oxygen induced strong green light emission from low-temperature grown amorphous silicon nitride films

Luminescent amorphous silicon nitride films were fabricated by plasma-enhanced chemical vapor deposition at room temperature followed by thermal oxidation at 100 degrees C. Very bright green emissions were clearly observed with the naked eye in a bright room after the samples had been oxidized. The emission peak is located at 495 nm. Fourier-transform infrared absorption spectra and results of depth profiling with x-ray photoelectron spectroscopy indicate that the introduction of oxygen is of a key role in enhancing the photoluminescence intensity of the films. Emission and excitation spectra analyses suggest that the green emission is originated from the radiative recombination in the localized states related to the Si-O bonds. (c) 2006 American Institute of Physics.