Effect of nitrogen content on electronic structure and properties of SiBCN materials

Amorphous SiBCN materials were prepared using reactive magnetron sputtering, and their structure, electronic structure and electrical and optical properties were studied using a combined approach of experiment and ab initio calculations. We focus on the effect of N content over a wide range on the material properties. We find that decreasing the N content (from 54 to 0 at.%) decreases the electrical resistivity (from >108 to 0.2 Ω m) and the optical gap (from 3.5 eV to almost 0), and explain the effect in terms of the band gap and the localization of electronic states. The results allow one to tailor SiBCN compositions which can combine different functional properties, such as high thermal stability and electrical conductivity.