The dissociation of the MgH complex in GaN under low-energy electron-beam irradiation and its re-association during post-irradiation annealing were measured by using infra-red vibration spectroscopy. The dissociation rate exhibited a pronounced dependence upon the H isotope, being about 4 times greater for protium than for D. Re-association occurred at temperatures below 200C, which may be problematic for device applications of low-energy electron-beam irradiation. Possible reaction paths based upon atomic configurations from density-functional theory were considered and bond-excitation mechanisms were investigated in surface-desorption studies, thereby arriving at a model of the evolution which was consistent with the experimental results.

Electron-Beam Dissociation of the MgH Complex in p-Type GaN. S.M.Myers, C.H.Seager, A.F.Wright, B.L.Vaandrager, J.S.Nelson: Journal of Applied Physics, 2002, 92[11], 6630-5