Thermal stability of H2-implanted n- and p-type GaN

Implantation of H+2 into n- and p-type GaN creates high resistivity material in which the resistance displays activation energies of 0.8 and 0.9 eV, respectively. Annealing at 500 °C restores the initial, preimplanted resistance of the n-GaN, due to removal of the deep trap states created by the ion stopping. By contrast, in p-type GaN annealing at 500 °C produces motion of the implanted deuterium and formation of Mg–H complexes that keep the resistance high. About 20% of the deuterium remains in n-GaN even after annealing at 1200 °C, where it decorates the residual implant damage. In p-type GaN all of the deuterium is evolved from the crystal by 1000 °C.