Defect centers in α-SiNx:: Electronic and structural properties

By combining ab initio methods and interatomic potentials, we investigated the electronic and the structural properties of amorphous silicon nitride. Our results show the trends on the electronic band structure of SiNx (0.5 < x < 1.8) as the nitrogen content changes, and are in good agreement with the experimental data. Hydrogenation of the systems was found to considerably reduce the number of energy levels in the gap. The energy levels which appeared in the materials band gap were compared to the electrically active centers, which have been identified by electron-paramagnetic resonance experiments.