Point defect luminescence associated with stacking faults in magnesium doped zincblende GaN
Abstract
The luminescence characteristics and the relation between the distribution of impurities and stacking faults (SFs) in Mg-doped zincblende gallium nitride (zb-GaN:Mg) have been investigated by cathodoluminescence (CL) and atom probe tomography (APT). Four peaks have been identified in the CL emission spectrum, and the possible related recombination mechanisms have been proposed. The main peak at 3.23 eV is associated with excitonic transitions, while the other three, having lower energies at about 3.15, 3.02, and 2.92 eV, respectively, are related to donor-to-acceptor (DAP) transitions involving different acceptor energy levels. These DAP peaks were significantly more intense on or close to SFs compared to the surrounding defect-free material, indicating an enrichment of point defects near SFs. This finding was supported by APT measurements, where Mg showed a tendency to segregate toward SFs in zb-GaN.
Article Details
Journal Info
Journal of Applied Physics
American Institute of Physics
Authors (10)
Xiuyuan Xu
Department of Materials Science and Metallurgy, University of Cambridge 1 , 27 Charles Babbage Rd, Cambridge CB3 0FS,
Martin Frentrup
Department of Materials Science and Metallurgy, University of Cambridge 1 , 27 Charles Babbage Road, Cambridge CB3 0FS,
Gunnar Kusch
Department of Materials Science and Metallurgy
Ruiying Shu
Department of Materials, University of Oxford 2 , Parks Road, Oxford OX1 3PH,
Christina Hofer
Department of Materials, University of Oxford 2 , Parks Road, Oxford OX1 3PH,
Paul A. J. Bagot
Department of Materials, University of Oxford 2 , Parks Road, Oxford OX1 3PH,
Michael P. Moody
Department of Materials, University of Oxford 2 , Parks Road, Oxford OX1 3PH,
Menno J. Kappers
Department of Materials Science and Metallurgy, University of Cambridge 1 , 27 Charles Babbage Road, Cambridge CB3 0FS,
David J. Wallis
Department of Materials Science and Metallurgy, University of Cambridge 1 , 27 Charles Babbage Road, Cambridge CB3 0FS,
Rachel A. Oliver
Department of Materials Science and Metallurgy