Spectroscopic study of Nd-doped amorphous SiN films

An extended and systematic spectroscopic study on Nd doped amorphous silicon-nitrogen alloys was presented. The samples, prepared in the form of thin films were submitted to cumulative thermal annealing treatments under highly controllable conditions. All the as-deposited films were found to exhibit an optical band gap of ∼5 eV which were essentially amorphous. Even after thermal annealing at 1000°C, no evidence of crystals involving either Si-Si or Si-N bonds was found, which indicated that the films remained amorphous.