摘要
对大功率GaN基白光LED在85℃下进行了高温加速老化实验。经6 500 h的老化,样品光通量退化幅度为28%～33%。样品的I-V特性变化表明其串联电阻和反向漏电流不断增大,原因可归结为芯片欧姆接触的退化及芯片材料中缺陷密度的提高。样品的热特性变化显示出各结构层热阻均明显增大,这是由散热通道上各层材料的老化及焊料层出现大面积空洞引起的。分析表明,高温老化过程中芯片和封装材料的退化共同导致了LED的缓变失效。
Accelerated aging test at the temperature of 85 ℃ were carried out on high-power GaN-based white light-emitting diodes.The degradation of main performance parameters was investigated.After 6 500 h,the luminous flux rate of the samples was declined about 28% to 33%.Series resistance and reverse leakage current increased with the aging time,which were caused by the degradation of ohmic contact and the increase of the defect density,respectively.The thermal resistance components of LEDs increased gradually.Based on the C-SAM measurement,some voids appeared in the die attach.The experiment results suggested that the degradation both in chip and packaging lead to the invalidation devices.
出处
《发光学报》
EI
CAS
CSCD
北大核心
2011年第10期1046-1050,共5页
Chinese Journal of Luminescence
基金
北京市自然科学基金(4092005)
国家"863"计划(2009AA032704)
教育部博士点基金(20091103110006)资助项目
关键词
大功率白光LED
老化
热阻
失效分析
high-power white LED
aging test
thermal resistance
failure analysis
作者简介
周舟（1987-），男，江苏盐城人，主要从事大功率白光LED的可靠性的研究。E-mail：zhouzhou-bj@163．com
通讯联系人；E—mail：shwfeng@b_jut．edu．cn
