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Title: High dose Co-60 gamma irradiation of InGaN quantum well light-emitting diodes

Abstract

InGaN multiquantum-well light-emitting diodes (LEDs) in the form of unpackaged die with emission wavelengths from 410 to 510 nm were irradiated with {sup 60}Co {gamma}-rays with doses in the range 150-2000 Mrad (Si). The forward turn-on voltage for all the irradiated LEDs was increased slightly (e.g., by only {approx}0.1-0.15 V for 500 MRad dose irradiation) while the reverse breakdown voltage was unchanged within experimental error. The light output intensity for the 410 nm diodes was decreased by 20% after a dose of 150 MRad and 75% after {approx}2 GRad. The current transport in the LEDs was dominated by generation-recombination (ideality factor {approx}2) both before and after irradiation. The morphology and appearance of the p and n-Ohmic metallization did not show any detectable change as a result of even the highest {gamma}-ray dose.

Authors:
; ; ; ; ;  [1];  [2];  [2];  [2]
  1. Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States)
  2. (United States)
Publication Date:
OSTI Identifier:
20706432
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 87; Journal Issue: 21; Other Information: DOI: 10.1063/1.2132085; (c) 2005 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; BREAKDOWN; CHARGED-PARTICLE TRANSPORT; COBALT 60; ELECTRIC POTENTIAL; GALLIUM NITRIDES; GAMMA RADIATION; INDIUM NITRIDES; IRRADIATION; LIGHT EMITTING DIODES; MORPHOLOGY; QUANTUM WELLS; RECOMBINATION; SEMICONDUCTOR MATERIALS; WAVELENGTHS

Citation Formats

Khanna, Rohit, Han, S.Y., Pearton, S.J., Schoenfeld, D., Schoenfeld, W.V., Ren, F., Department of Nuclear and Radiological Engineering, University of Florida, Gainesville, Florida 32611, CREOL, University of Central Florida, Orlando, Florida 32816, and Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611. High dose Co-60 gamma irradiation of InGaN quantum well light-emitting diodes. United States: N. p., 2005. Web. doi:10.1063/1.2132085.
Khanna, Rohit, Han, S.Y., Pearton, S.J., Schoenfeld, D., Schoenfeld, W.V., Ren, F., Department of Nuclear and Radiological Engineering, University of Florida, Gainesville, Florida 32611, CREOL, University of Central Florida, Orlando, Florida 32816, & Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611. High dose Co-60 gamma irradiation of InGaN quantum well light-emitting diodes. United States. doi:10.1063/1.2132085.
Khanna, Rohit, Han, S.Y., Pearton, S.J., Schoenfeld, D., Schoenfeld, W.V., Ren, F., Department of Nuclear and Radiological Engineering, University of Florida, Gainesville, Florida 32611, CREOL, University of Central Florida, Orlando, Florida 32816, and Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611. Mon . "High dose Co-60 gamma irradiation of InGaN quantum well light-emitting diodes". United States. doi:10.1063/1.2132085.
@article{osti_20706432,
title = {High dose Co-60 gamma irradiation of InGaN quantum well light-emitting diodes},
author = {Khanna, Rohit and Han, S.Y. and Pearton, S.J. and Schoenfeld, D. and Schoenfeld, W.V. and Ren, F. and Department of Nuclear and Radiological Engineering, University of Florida, Gainesville, Florida 32611 and CREOL, University of Central Florida, Orlando, Florida 32816 and Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611},
abstractNote = {InGaN multiquantum-well light-emitting diodes (LEDs) in the form of unpackaged die with emission wavelengths from 410 to 510 nm were irradiated with {sup 60}Co {gamma}-rays with doses in the range 150-2000 Mrad (Si). The forward turn-on voltage for all the irradiated LEDs was increased slightly (e.g., by only {approx}0.1-0.15 V for 500 MRad dose irradiation) while the reverse breakdown voltage was unchanged within experimental error. The light output intensity for the 410 nm diodes was decreased by 20% after a dose of 150 MRad and 75% after {approx}2 GRad. The current transport in the LEDs was dominated by generation-recombination (ideality factor {approx}2) both before and after irradiation. The morphology and appearance of the p and n-Ohmic metallization did not show any detectable change as a result of even the highest {gamma}-ray dose.},
doi = {10.1063/1.2132085},
journal = {Applied Physics Letters},
number = 21,
volume = 87,
place = {United States},
year = {Mon Nov 21 00:00:00 EST 2005},
month = {Mon Nov 21 00:00:00 EST 2005}
}
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