Research of n-type arsenic doped diamond: Theoretical analysis of electronic and mechanical properties

Abstract

Substitutional defects of arsenic in diamond have been investigated in terms of the ionization energy, electronic property, and elastic constants for one and two arsenic doped configurations by density functional theory. Arsenic (As) particle doped diamond has been found to present attractive n-type doping properties. The ionization energy has been calculated based on different exchange-correlation functionals and competitive ionization energies are exhibited for one As atom doped and two As atoms doped (separated by one carbon atom) models. Besides, doping activities make the band gaps decrease for all configurations with the band structure of single As atom and separated site doped configurations remaining indirect, while the adjacent site of configuration with two As atoms has a direct band structure. Moreover, As doping makes the Young's module of diamond decrease and the elastic constants of adjacent site configuration present metastable state. Finally, one arsenic particle adsorption on diamond (001) surface has also been studied. It is identified that Bridge site is the most suitable adsorption site for arsenic doping during diamond growth process. As a conclusion, arsenic impurity is believed to be a competitive candidate of n-type doped diamond.