The diffusion of Mg in layer samples was investigated by using otherwise undoped GaN test structures which contained three Mg-dopant spikes. These simplified structures permitted accurate dopant profiling to be performed by avoiding the formation of non-planar V-shaped defects; as confirmed by atomic force microscopy. The Mg distribution in GaN/AlGaN heterostructures was also studied. In all cases, no significant Mg diffusion or segregation behavior was observed during 1.25h at 1060C.

Study of Mg diffusion during metalorganic chemical vapor deposition of GaN and AlGaN Y.L.Chang, M.Ludowise, D.Lefforge, B.Perez: Applied Physics Letters, 1999, 74[5], 688-90