The effects of p-type dopants on the structural and electronic properties of n-type intrinsic GaN systems were investigated using a first-principles approach. Nitrogen vacancies and oxygen substitutions were intentionally used to obtain an n-type intrinsic GaN system. The formation energy of the Be-doped n-type intrinsic GaN system based on nitrogen vacancies depended strongly on concentration, with a maximum energy difference of 4.87 eV. The incorporation of metallic cations (Be, Mg, and Zn) led to the formation of a p-type GaN system with desirable electronic properties that were attributed to charge transfer from partially occupied Ga-, N-, and O-s states to the p states of the metallic cations.

Keywords: First-principles; GaN; LED; Be doping; Mg doping; Zn doping