Materials Design for the Fabrication of Low-Resistivity p-Type GaN Using a Codoping Method

Abstract

On the basis of band-theoretical investigation using the augmented-spherical-wave (ASW) method, we propose a valence-control method, the “codoping method”, to fabricate low-resistivity p -type GaN materials. p -type dopants lead to an increase in the electrostatic energy in GaN materials. This gives rise to destabilization of ionic charge distributions due to a shift of N 2 p levels towards higher energy regions. We clarified that codoping of n -type dopants, Si or O atoms, lead to a stable p -type GaN:Mg atom material and investigated differences in the roles of Si and O on the fabrication of low-resistivity p -type GaN materials.