Redistribution of Mg and H atoms in Mg-implanted GaN through ultra-high-pressure annealing

Diffusion in a magnesium (Mg)-implanted homoepitaxial GaN layer during ultra-high-pressure annealing (UHPA, in ambient nitrogen, under 1 GPa) was investigated. Annealing at 1573 K resulted in Mg-segregation at the edge of the implanted region, which was suppressed using a higher temperature of 1673 K. Hydrogen (H) atoms were incorporated during the UHPA, resulting in the Mg and H developing the same diffusion profile in the deeper region. The diffusion coefficient of the Mg-implanted sample was 3.3 x 10(-12) cm(2) s(-1)at 1673 K from the annealing duration dependence, 30 times larger than that of the epitaxial Mg-doped sample, originating from ion implantation-induced defects.