We report ab initio molecular dynamics simulations of the preparation of $\mathrm{C}{\mathrm{N}}_x$, BCN, and SiBCN materials formed by energetic-ion-assisted deposition techniques. We focus on the formation of ${\mathrm{N}}_2$ molecules during liquid-quench simulations and investigate how density, temperature, and quench rate affect the number of ${\mathrm{N}}_2$ molecules formed in the network. We find that higher material density and shorter cooling times lead to reduced ${\mathrm{N}}_2$ formation and thus higher nitrogen incorporation into the structure. These results suggest a modification of common physical vapor deposition techniques to enhance N content in materials such as $\mathrm{C}{\mathrm{N}}_x$.

• Received 8 November 2004

DOI:https://doi.org/10.1103/PhysRevB.72.054204