An emission, D20,X, which was located at 3.48eV in the near band-edge spectrum at low temperatures was investigated by using photoluminescence techniques. This emission was close in energy to the well-studied neutral-donor bound-exciton line, D0,X. Excitation power and temperature-dependent data indicated that this emission was related to a bound exciton complex. Annealing at 440C resulted in a marked reduction in the photoluminescence intensity of this emission. A model was proposed in which the exciton-binding center which was responsible for the D20,X emission consisted of a shallow donor-H complex that formed during growth. Annealing at 440C resulted in the dissociation of this complex, and reduced the photoluminescence intensity of the D20,X emission.

Donor-Hydrogen Bound Exciton in Epitaxial GaN D.G.Chtchekine, Z.C.Feng, G.D.Gilliland, S.J.Chua, D.Wolford: Physical Review B, 1999, 60[23], 15980-4