標題: Failure and degradation mechanisms of high-power white light emitting diodes
作者: Yang, Shih-Chun
Lin, Pang
Wang, Chien-Ping
Huang, Sheng Bang
Chen, Chiu-Ling
Chiang, Pei-Fang
Lee, An-Tse
Chu, Mu-Tao
材料科學與工程學系
Department of Materials Science and Engineering
公開日期: 1-七月-2010
摘要: The investigation explores the factors that influence the long-term performance of high-power 1 W white light emitting diodes (LEDs). LEDs underwent an aging test in which they were exposed to various temperatures and electrical currents, to identify both their degradation mechanisms and the limitations of the LED chip and package materials. The degradation rates of luminous flux increased with electrical and thermal stresses. High electric stress induced surface and bulk defects in the LED chip during short-term aging, which rapidly increased the leakage current. Yellowing and cracking of the encapsulating lens were also important in package degradation at 0.7 A/85 degrees C and 0.7 A/55 degrees C. This degradation reduced the light extraction efficiency to an extent that is strongly related to junction temperature and the period of aging. junction temperatures were measured at various stresses to determine the thermal contribution and the degradation mechanisms. The results provided a complete understanding of the degradation mechanisms of both chip and package, which is useful in designing highly reliable and long-lifetime LEDs. Crown Copyright (C) 2010 Published by Elsevier Ltd. All rights reserved.
URI: http://dx.doi.org/10.1016/j.microrel.2010.03.007
http://hdl.handle.net/11536/5175
ISSN: 0026-2714
DOI: 10.1016/j.microrel.2010.03.007
期刊: MICROELECTRONICS RELIABILITY
Volume: 50
Issue: 7
起始頁: 959
結束頁: 964
顯示於類別:期刊論文


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  1. 000279527900011.pdf