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Title: Effect of the joule heating on the quantum efficiency and choice of thermal conditions for high-power blue InGaN/GaN LEDs

Abstract

The heat model of a light-emitting diode (LED) with an InGaN/GaN quantum well (QW) in the active region is considered. Effects of the temperature and drive current, as well as of the size and material of the heat sink on the light output and efficiency of blue LEDs are studied. It is shown that, for optimal heat removal, decreasing of the LED efficiency as current increases to 100 mA is related to the effect of electric field on the efficiency of carrier injection into the QW. As current further increases up to 400 mA, the decrease in efficiency is caused by Joule heating. It is shown that the working current of LEDs can be increased by a factor of 5-7 under optimal heat removal conditions. Recommendations are given on the cooling of LEDs in a manner dependent on their power.

Authors:
 [1]; ; ; ; ; ;  [2]
  1. St. Petersburg State Polytechnical University (Russian Federation), E-mail: eartm@mail.ru
  2. Russian Academy of Sciences, Ioffe Physicotechnical Institute (Russian Federation)
Publication Date:
OSTI Identifier:
21088539
Resource Type:
Journal Article
Resource Relation:
Journal Name: Semiconductors; Journal Volume: 40; Journal Issue: 5; Other Information: DOI: 10.1134/S1063782606050162; Copyright (c) 2006 Nauka/Interperiodica; Article Copyright (c) 2006 Pleiades Publishing, Inc; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; GALLIUM NITRIDES; HEAT; HEAT SINKS; INDIUM NITRIDES; JOULE HEATING; LIGHT EMITTING DIODES; QUANTUM EFFICIENCY; QUANTUM WELLS

Citation Formats

Efremov, A. A., Bochkareva, N. I., Gorbunov, R. I., Lavrinovich, D. A., Rebane, Yu. T., Tarkhin, D. V., and Shreter, Yu. G. Effect of the joule heating on the quantum efficiency and choice of thermal conditions for high-power blue InGaN/GaN LEDs. United States: N. p., 2006. Web. doi:10.1134/S1063782606050162.
Efremov, A. A., Bochkareva, N. I., Gorbunov, R. I., Lavrinovich, D. A., Rebane, Yu. T., Tarkhin, D. V., & Shreter, Yu. G. Effect of the joule heating on the quantum efficiency and choice of thermal conditions for high-power blue InGaN/GaN LEDs. United States. doi:10.1134/S1063782606050162.
Efremov, A. A., Bochkareva, N. I., Gorbunov, R. I., Lavrinovich, D. A., Rebane, Yu. T., Tarkhin, D. V., and Shreter, Yu. G. Mon . "Effect of the joule heating on the quantum efficiency and choice of thermal conditions for high-power blue InGaN/GaN LEDs". United States. doi:10.1134/S1063782606050162.
@article{osti_21088539,
title = {Effect of the joule heating on the quantum efficiency and choice of thermal conditions for high-power blue InGaN/GaN LEDs},
author = {Efremov, A. A. and Bochkareva, N. I. and Gorbunov, R. I. and Lavrinovich, D. A. and Rebane, Yu. T. and Tarkhin, D. V. and Shreter, Yu. G.},
abstractNote = {The heat model of a light-emitting diode (LED) with an InGaN/GaN quantum well (QW) in the active region is considered. Effects of the temperature and drive current, as well as of the size and material of the heat sink on the light output and efficiency of blue LEDs are studied. It is shown that, for optimal heat removal, decreasing of the LED efficiency as current increases to 100 mA is related to the effect of electric field on the efficiency of carrier injection into the QW. As current further increases up to 400 mA, the decrease in efficiency is caused by Joule heating. It is shown that the working current of LEDs can be increased by a factor of 5-7 under optimal heat removal conditions. Recommendations are given on the cooling of LEDs in a manner dependent on their power.},
doi = {10.1134/S1063782606050162},
journal = {Semiconductors},
number = 5,
volume = 40,
place = {United States},
year = {Mon May 15 00:00:00 EDT 2006},
month = {Mon May 15 00:00:00 EDT 2006}
}
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