Optical properties of heavily Mg-doped p-GaN films prepared by reactive ion etching

The effect of the damage caused by reactive ion etching on the optical properties of heavily Mg-doped p-type GaN (p-GaN) was investigated in this study. After etching, we found that the blue luminescence (BL) is redshifted and the intensity of the redshifted BL is markedly increased at room temperature, which are attributed to the formation of the lattice disorder resulting in the domination of distant donor-acceptor pairs (DAPs) and the formation of more nitrogen-vacancy-related defects resulting in more recombination centers D responsible for DAP transition.