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Title: Enhanced internal quantum efficiency and light extraction efficiency from textured GaN/AlGaN quantum wells grown by molecular beam epitaxy

Abstract

GaN/Al{sub 0.2}Ga{sub 0.8}N multiple quantum wells (MQWs) were grown by molecular beam epitaxy on randomly textured and atomically smooth (0001) GaN templates. Smooth and textured GaN templates were deposited on (0001) sapphire substrates by varying the III/V ratio and the substrate temperature during growth by the hydride vapor-phase epitaxy method. We find that the MQWs replicate the texture of the GaN template, which was found to have a Gaussian distribution. The peak photoluminescence intensity from the textured MQWs is always higher than from the smooth MQWs and for GaN (7 nm)/Al{sub 0.2}Ga{sub 0.8}N (8 nm) MQWs, it is 700 times higher than that from similarly produced MQWs on smooth GaN templates. This result is attributed partly to the enhancement in light extraction efficiency and partly to the enhancement in internal quantum efficiency. The origin of the increase in internal quantum efficiency is partly due to the reduction of the quantum-confined Stark effect, since the polarization vector intersects the quantum well (QW) planes at angles smaller than 90 deg. , and partly due to the charge redistribution in the QWs caused by the polarization component parallel to the planes of the QWs.

Authors:
; ; ; ; ;  [1]
  1. Department of Electrical and Computer Engineering, Boston University, Boston, Massachusetts 02215 (United States)
Publication Date:
OSTI Identifier:
20787979
Resource Type:
Journal Article
Journal Name:
Journal of Applied Physics
Additional Journal Information:
Journal Volume: 99; Journal Issue: 6; Other Information: DOI: 10.1063/1.2179120; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0021-8979
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALUMINIUM NITRIDES; CRYSTAL GROWTH; GALLIUM NITRIDES; HYDRIDES; MOLECULAR BEAM EPITAXY; PHOTOLUMINESCENCE; QUANTUM EFFICIENCY; QUANTUM WELLS; SAPPHIRE; SEMICONDUCTOR MATERIALS; SUBSTRATES; TEXTURE; VAPOR PHASE EPITAXY

Citation Formats

Cabalu, J S, Thomidis, C, Moustakas, T D, Riyopoulos, S, Lin, Zhou, Smith, David J, Science Applications International Corporation, 1710 SAIC Drive, MS 2-3-1 McLean, Virginia 22102, and Center for Solid State Science, and Department of Physics and Astronomy, Arizona State University, Tempe, Arizona 85287. Enhanced internal quantum efficiency and light extraction efficiency from textured GaN/AlGaN quantum wells grown by molecular beam epitaxy. United States: N. p., 2006. Web. doi:10.1063/1.2179120.
Cabalu, J S, Thomidis, C, Moustakas, T D, Riyopoulos, S, Lin, Zhou, Smith, David J, Science Applications International Corporation, 1710 SAIC Drive, MS 2-3-1 McLean, Virginia 22102, & Center for Solid State Science, and Department of Physics and Astronomy, Arizona State University, Tempe, Arizona 85287. Enhanced internal quantum efficiency and light extraction efficiency from textured GaN/AlGaN quantum wells grown by molecular beam epitaxy. United States. doi:10.1063/1.2179120.
Cabalu, J S, Thomidis, C, Moustakas, T D, Riyopoulos, S, Lin, Zhou, Smith, David J, Science Applications International Corporation, 1710 SAIC Drive, MS 2-3-1 McLean, Virginia 22102, and Center for Solid State Science, and Department of Physics and Astronomy, Arizona State University, Tempe, Arizona 85287. Wed . "Enhanced internal quantum efficiency and light extraction efficiency from textured GaN/AlGaN quantum wells grown by molecular beam epitaxy". United States. doi:10.1063/1.2179120.
@article{osti_20787979,
title = {Enhanced internal quantum efficiency and light extraction efficiency from textured GaN/AlGaN quantum wells grown by molecular beam epitaxy},
author = {Cabalu, J S and Thomidis, C and Moustakas, T D and Riyopoulos, S and Lin, Zhou and Smith, David J and Science Applications International Corporation, 1710 SAIC Drive, MS 2-3-1 McLean, Virginia 22102 and Center for Solid State Science, and Department of Physics and Astronomy, Arizona State University, Tempe, Arizona 85287},
abstractNote = {GaN/Al{sub 0.2}Ga{sub 0.8}N multiple quantum wells (MQWs) were grown by molecular beam epitaxy on randomly textured and atomically smooth (0001) GaN templates. Smooth and textured GaN templates were deposited on (0001) sapphire substrates by varying the III/V ratio and the substrate temperature during growth by the hydride vapor-phase epitaxy method. We find that the MQWs replicate the texture of the GaN template, which was found to have a Gaussian distribution. The peak photoluminescence intensity from the textured MQWs is always higher than from the smooth MQWs and for GaN (7 nm)/Al{sub 0.2}Ga{sub 0.8}N (8 nm) MQWs, it is 700 times higher than that from similarly produced MQWs on smooth GaN templates. This result is attributed partly to the enhancement in light extraction efficiency and partly to the enhancement in internal quantum efficiency. The origin of the increase in internal quantum efficiency is partly due to the reduction of the quantum-confined Stark effect, since the polarization vector intersects the quantum well (QW) planes at angles smaller than 90 deg. , and partly due to the charge redistribution in the QWs caused by the polarization component parallel to the planes of the QWs.},
doi = {10.1063/1.2179120},
journal = {Journal of Applied Physics},
issn = {0021-8979},
number = 6,
volume = 99,
place = {United States},
year = {2006},
month = {3}
}