Nitrogen Vacancies and Oxygen Substitution of Ta3N5: First-Principles Investigation

Typically, N vacancies or O substitution may exist in synthesized compounds owing to chemical reactions. Using the density functional theory, we clarified the effects of N vacancies and O substitution on Ta3N5 at doping concentrations of 2.5 and 5% by calculating the resulting structures, stabilities, and other physical properties. The calculations predicted that N vacancies will destabilize Ta3N5 and that O substitution will increase its stability. Moreover, pure Ta3N5 exhibits semiconductor characteristics but N vacancies or O substitution may lead to the degenerated semiconducting behavior of Ta3N5.