Photoluminescence with ultra-wide spectrum from radiative defects in Si-rich SiN_x

The photoluminescence spectra of amorphous silicon rich silicon nitride films with various compositions were investigated. Two main luminescence peaks were identified for all samples and blueshift of photoluminescence were observed after annealing treatment. With the help of X-ray photoelectron spectroscopy and Fourier transform infrared measurement, the chemical composition and bonding environment of samples, which were grown with different reactant gases flow rates of plasma enhanced chemical vapor deposition, were analyzed. According to all these measurement results, it is confirmed that the main luminescence centers are radiative recombination defects, such as silicon and nitride dangling bonds. With proper deposition conditions, all these radiative recombination defects could be activated at the same time, so that ultra-wide photoluminescence spectra with full width at half maximum of about 250nm ∼ 300nm were obtained in visible region.