Deuterated p-type GaN(Mg,2H) films were irradiated at room temperature with 1MeV protons to create native point defects with a concentration approximately equal to the Mg doping (5 x 1019/cm3). The samples were then annealed isothermally at a succession of temperatures while monitoring the infrared absorption due to the H local mode of the MgH defect. As the samples were annealed, the MgH absorption signal decreased and a new mode at slightly higher frequency appeared, which was associated with the approach of a mobile N interstitial. The time-dependence of the MgH absorption was used to determine the diffusion barrier of the N interstitial in p-type GaN to be 1.99eV. This was in good agreement with theoretical calculations of N interstitial motion in GaN.

Measurement of Temperature-Dependent Defect Diffusion in Proton-Irradiated GaN(Mg, H). R.M.Fleming, S.M.Myers: Journal of Applied Physics, 2006, 100[4], 043513