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Title: Low energy electron beam induced vacancy activation in GaN

Abstract

Experimental evidence on low energy electron beam induced point defect activation in GaN grown by metal-organic vapor phase epitaxy (MOVPE) is presented. The GaN samples are irradiated with a 5-20 keV electron beam of a scanning electron microscope and investigated by photoluminescence and positron annihilation spectroscopy measurements. The degradation of the band-to-band luminescence of the irradiated GaN films is associated with the activation of point defects. The activated defects were identified as in-grown Ga-vacancies. We propose that MOVPE-GaN contains a significant concentration of passive V{sub Ga}-H{sub n} complexes that can be activated by H removal during low energy electron irradiation.

Authors:
; ;  [1];  [2];  [3];  [2]
  1. Department of Micro- and Nanosciences, Aalto University, P.O. Box 13500, FI-00076 Aalto (Finland)
  2. Department of Applied Physics, Aalto University, P.O. Box 11100, FI-00076 Aalto (Finland)
  3. (Poland)
Publication Date:
OSTI Identifier:
22025478
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 100; Journal Issue: 12; Other Information: (c) 2012 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ANNIHILATION; CHEMICAL VAPOR DEPOSITION; CRYSTALS; ELECTRON BEAMS; ELECTRONS; GALLIUM NITRIDES; IRRADIATION; KEV RANGE; LAYERS; ORGANOMETALLIC COMPOUNDS; PHOTOLUMINESCENCE; PHYSICAL RADIATION EFFECTS; POSITRONS; SCANNING ELECTRON MICROSCOPY; SEMICONDUCTOR MATERIALS; VACANCIES; VAPOR PHASE EPITAXY

Citation Formats

Nykaenen, H., Suihkonen, S., Sopanen, M., Kilanski, L., Institute of Physics, Polish Academy of Sciences, Al. Lotnikow 32/56, 02-668 Warsaw, and Tuomisto, F. Low energy electron beam induced vacancy activation in GaN. United States: N. p., 2012. Web. doi:10.1063/1.3696047.
Nykaenen, H., Suihkonen, S., Sopanen, M., Kilanski, L., Institute of Physics, Polish Academy of Sciences, Al. Lotnikow 32/56, 02-668 Warsaw, & Tuomisto, F. Low energy electron beam induced vacancy activation in GaN. United States. doi:10.1063/1.3696047.
Nykaenen, H., Suihkonen, S., Sopanen, M., Kilanski, L., Institute of Physics, Polish Academy of Sciences, Al. Lotnikow 32/56, 02-668 Warsaw, and Tuomisto, F. 2012. "Low energy electron beam induced vacancy activation in GaN". United States. doi:10.1063/1.3696047.
@article{osti_22025478,
title = {Low energy electron beam induced vacancy activation in GaN},
author = {Nykaenen, H. and Suihkonen, S. and Sopanen, M. and Kilanski, L. and Institute of Physics, Polish Academy of Sciences, Al. Lotnikow 32/56, 02-668 Warsaw and Tuomisto, F.},
abstractNote = {Experimental evidence on low energy electron beam induced point defect activation in GaN grown by metal-organic vapor phase epitaxy (MOVPE) is presented. The GaN samples are irradiated with a 5-20 keV electron beam of a scanning electron microscope and investigated by photoluminescence and positron annihilation spectroscopy measurements. The degradation of the band-to-band luminescence of the irradiated GaN films is associated with the activation of point defects. The activated defects were identified as in-grown Ga-vacancies. We propose that MOVPE-GaN contains a significant concentration of passive V{sub Ga}-H{sub n} complexes that can be activated by H removal during low energy electron irradiation.},
doi = {10.1063/1.3696047},
journal = {Applied Physics Letters},
number = 12,
volume = 100,
place = {United States},
year = 2012,
month = 3
}
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