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Title: Bias dependence and correlation of the cathodoluminescence and electron beam induced current from an InGaN/GaN light emitting diode

Abstract

Micron-scale mapping has been employed to study a contacted InGaN/GaN LED using combined electroluminescence (EL), cathodoluminescence (CL), and electron beam induced current (EBIC). Correlations between parameters, such as the EBIC and CL intensity, were studied as a function of applied bias. The CL and EBIC maps reveal small areas, 2–10 μm in size, which have increased nonradiative recombination rate and/or a lower conductivity. The CL emission from these spots is blue shifted, by 30–40 meV. Increasing the reverse bias causes the size of the spots to decrease, due to competition between in-plane diffusion and drift in the growth direction. EL mapping shows large bright areas (∼100 μm) which also have increased EBIC, indicating domains of increased conductivity in the p and/or n-GaN.

Authors:
; ;  [1]; ; ; ;  [2]; ; ;  [3]
  1. Department of Physics, SUPA, University of Strathclyde, Glasgow G4 0NG (United Kingdom)
  2. Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB2 3QZ (United Kingdom)
  3. Department of Electronic and Electrical Engineering, University of Bath, Bath BA2 7AY (United Kingdom)
Publication Date:
OSTI Identifier:
22308699
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 116; Journal Issue: 3; Other Information: (c) 2014 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CATHODOLUMINESCENCE; CORRELATIONS; CRYSTAL GROWTH; DIFFUSION; ELECTRIC FIELDS; ELECTROLUMINESCENCE; GALLIUM NITRIDES; INDIUM COMPOUNDS; LIGHT EMITTING DIODES; RECOMBINATION; SCANNING ELECTRON MICROSCOPY

Citation Formats

Wallace, M. J., Edwards, P. R., Martin, R. W., Kappers, M. J., Oehler, F., Oliver, R. A., Humphreys, C. J., Hopkins, M. A., Sivaraya, S., and Allsopp, D. W. E.. Bias dependence and correlation of the cathodoluminescence and electron beam induced current from an InGaN/GaN light emitting diode. United States: N. p., 2014. Web. doi:10.1063/1.4890497.
Wallace, M. J., Edwards, P. R., Martin, R. W., Kappers, M. J., Oehler, F., Oliver, R. A., Humphreys, C. J., Hopkins, M. A., Sivaraya, S., & Allsopp, D. W. E.. Bias dependence and correlation of the cathodoluminescence and electron beam induced current from an InGaN/GaN light emitting diode. United States. doi:10.1063/1.4890497.
Wallace, M. J., Edwards, P. R., Martin, R. W., Kappers, M. J., Oehler, F., Oliver, R. A., Humphreys, C. J., Hopkins, M. A., Sivaraya, S., and Allsopp, D. W. E.. Mon . "Bias dependence and correlation of the cathodoluminescence and electron beam induced current from an InGaN/GaN light emitting diode". United States. doi:10.1063/1.4890497.
@article{osti_22308699,
title = {Bias dependence and correlation of the cathodoluminescence and electron beam induced current from an InGaN/GaN light emitting diode},
author = {Wallace, M. J. and Edwards, P. R. and Martin, R. W. and Kappers, M. J. and Oehler, F. and Oliver, R. A. and Humphreys, C. J. and Hopkins, M. A. and Sivaraya, S. and Allsopp, D. W. E.},
abstractNote = {Micron-scale mapping has been employed to study a contacted InGaN/GaN LED using combined electroluminescence (EL), cathodoluminescence (CL), and electron beam induced current (EBIC). Correlations between parameters, such as the EBIC and CL intensity, were studied as a function of applied bias. The CL and EBIC maps reveal small areas, 2–10 μm in size, which have increased nonradiative recombination rate and/or a lower conductivity. The CL emission from these spots is blue shifted, by 30–40 meV. Increasing the reverse bias causes the size of the spots to decrease, due to competition between in-plane diffusion and drift in the growth direction. EL mapping shows large bright areas (∼100 μm) which also have increased EBIC, indicating domains of increased conductivity in the p and/or n-GaN.},
doi = {10.1063/1.4890497},
journal = {Journal of Applied Physics},
number = 3,
volume = 116,
place = {United States},
year = {Mon Jul 21 00:00:00 EDT 2014},
month = {Mon Jul 21 00:00:00 EDT 2014}
}
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