Nitrogen-doped β-Ga2O3 nanowires were prepared by annealing as-grown nanowires in an ammonia atmosphere. The optical properties of the N-doped Ga2O3 nanowires were studied by measuring photoluminescence and phosphorescence decay at 10 to 300K. The experimental results revealed that N doping in β-Ga2O3 nanowires induced a novel intensive red-light emission around 1.67eV, with a characteristic decay time around 136µs at 77K, much shorter than that of the blue emission (a decay time of 457µs). The time decay and temperature-dependent luminescence spectra were calculated theoretically based upon a donor-acceptor pair model, which was in excellent agreement with the experimental data. This result suggested that the observed novel red-light emission originates from the recombination of an electron trapped on a donor due to O vacancies and a hole trapped on an acceptor due to N doping.

Luminescence Emission Originating from Nitrogen Doping of β-Ga2O3 Nanowires. Y.P.Song, H.Z.Zhang, C.Lin, Y.W.Zhu, G.H.Li, F.H.Yang, D.P.Yu: Physical Review B, 2004, 69[7], 075304 (7pp)