Hydrogenation of GaN, AlN, and InN

Abstract

Hydrogen incorporation depths of ≥1 μm are measured for 2H plasma exposure of GaN and AlN at 250–400 °C for 30 min. The concentration of 2H incorporated is in the range 5–10×1017 cm−3 for GaN and 5–30×1018 cm−3 for AlN under these conditions. No redistribution of the hydrogen is observed for annealing temperatures up to 800 °C, but at 900 °C there is substantial loss of hydrogen from the samples. Similar results are obtained for 2H implantation into GaN, AlN, and InN, with no significant redistribution observed up to 500–600 °C in either AlN or InN, and motion only at 900 °C in GaN. The thermal stability of hydrogen in III-V nitrides explains previous results for Mg-doped GaN grown using NH3, where post-growth annealing at high temperatures was required to achieve appreciable doping efficiencies.