We report the observation of green emission centered at 500nm, accompanied with luminescence enhancement and spectral blue shift (∼31meV) in the bandedge emission from a-plane grown gallium nitride (GaN) passivated with gallium hydroxide (GaOOH). From study of the photo-current response and polarization-resolved low-temperature microphotoluminescence (μ-PL) we resolved an evolution of gain competition process between the green and the UV emission bands. By dissolving the oxide we recover the emission characteristics of the as-grown a-GaN. These observations can be ascribed to a formation of compressively-strained a-GaN due to a coherently grown GaOOH atop layer. The latter is responsible for the spectral blue shift and the generation of acceptor like deep-levels causing the green-band transition in the emission and photo-current response. Enhancement of bandedge emission from the oxide covered a-GaN is due to the GaOOH surface passivation effect which was prepared by the photo-enhance wet oxidation method.
|Number of pages||3|
|Journal||Physica Status Solidi (C) Current Topics in Solid State Physics|
|Publication status||Published - 2008 Dec 1|
|Event||7th International Conference of Nitride Semiconductors, ICNS-7 - Las Vegas, NV, United States|
Duration: 2007 Sep 16 → 2007 Sep 21
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics