Structural and electronic properties of nitrogen-terminated diamond (100) surfaces

Three types of nitrogen (N) coverage configurations of 1 ML-alpha, 1 ML-beta and 1 ML-gamma (ML: monolayer, 1 ML: one N atom per carbon atom) on diamond (100) surface are dynamically and thermally stable predicted by first-principles calculation. The electron affinities of the nitrogen-terminated diamond surfaces are positive of 3.03 eV, 2.87 eV and 2.64 eV for the cases of 1 ML-alpha, 1 ML-beta and 1 ML-gamma, in turn. The energy levels contributed from N-termination are presented in the bandgap of bulk diamond. This work provides theoretical guidance for the design and fabrication of N-terminated diamond-based electronic devices.