Carrier Dynamics Studies of Thick GaN Grown by HVPE


We present a comparison between optical properties of two samples grown by hydride vapor phase epitaxy, one directly on Sapphire substrate (non-ELO) and one epitaxial lateral overgrown (ELO) on SiO2 patterned Sapphire substrate. The ELO material shows an improvement of the UV emission and slight decrease of the yellow emission. The band edge emission is red shifted due to the relaxation of the compressive strain. In spite of the increase in the UV emission, the lifetime of the excitons in the ELO material is more than twice lower than non-ELO material. We attribute this to screening effects of the background electron concentration.

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Bunea, G.E., Ünlü, M.S. & Goldberg, B.B. Carrier Dynamics Studies of Thick GaN Grown by HVPE. MRS Online Proceedings Library 595, 1147 (1999).

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