The effect of a Mg-doped GaN cap layer on the optical properties of InGaN/AlGaN multiple quantum well structures

D. M. Graham*, P. Dawson, Y. Zhang, P. M.F.J. Costa, M. J. Kappers, C. J. Humphreys, E. J. Thrush

*Corresponding author for this work

Research output: Contribution to journalConference articlepeer-review

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We have studied the effect of depositing a Mg-doped GaN cap layer on near-ultraviolet emitting In0.05Ga0.95N/Al 0.05Ga0.95N multiple quantum well structures, using photoluminescence spectroscopy and transmission electron microscopy. The room temperature (T = 300 K) photoluminescence spectra revealed a reduction in the integrated photoluminescence intensity of the capped structure, which is shown by time decay measurements to be due to greater competition from non-radiative recombination processes. The structural analysis of the samples using electron microscopy has not shown any evidence of Mg-induced defects. We suggest that the non-radiative recombination path is related to the diffusion of Mg atoms into the quantum well region and the formation of Mg-nitrogen vacancy complexes.

Original languageEnglish (US)
Pages (from-to)2005-2008
Number of pages4
JournalPhysica Status Solidi (C) Current Topics in Solid State Physics
StatePublished - 2006
Event6th International Conference on Nitride Semiconductors, ICNS-6 - Bremen, Germany
Duration: Aug 28 2005Sep 2 2005

ASJC Scopus subject areas

  • Condensed Matter Physics

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