功率LED热特性分析  

Thermal Characters Analysis of Power LED

作　　者：毛德丰[1] 郭伟玲[1] 高国[1] 沈光地[1] 

机构地区：[1]北京工业大学北京光电子技术实验室,北京100124

出　　处：《照明工程学报》2009年第2期30-34,共5页China Illuminating Engineering Journal

基　　金：国家863计划项目资助(SQ2007AA03Z431230);北京市人才强教计划项目资助(05002015200504)

摘　　要：随着LED功率的升高,热应力对LED的影响越来越显著,过高的结温不但会使器件寿命急剧衰减,还会严重影响LED的峰值波长,光功率,光通量等诸多性能参数。因此精确掌握LED器件的温升规律便成为了提高设备工作可靠性和芯片结构设计的关键所在。本文通过标准电学法对不同颜色的1W功率LED及不同功率的GaN基白光LED的结温和热阻进行了测量,实验结果表明:同种结构LED的温度系数K虽然离散但比较接近,不同结构LED芯片K明显不同;在相同衬底材料,相同芯片结构条件下,LED芯片结温会随芯片功率的增大而升高。并首次进行了变电流下不同功率LED芯片的结温和热阻测量,发现无论功率大小,结温均随热电流的增大而上升,功率越大,上升幅度也越大。随着LED两端所加电流的增大,3W白光LED的热阻呈上升趋势,而1W白光LED的热阻随电流增加基本不变。In this paper, the thermal property of high power LED are introduced based on experimental data. The junction temperature and thermal resistance of different color 1 W LED is measured and analyzed. The green LED has higher temperature-voltage coefficient compared with others; the orang LED has lager thermal resistance compared with others. The junction temperature and thermal resistance of different power White LED are measured too. The results show that the higher of the LED power, the larger of the junction temperature and thermal resistance. It means for applications, lamp system designers must consider the dependence of the output power, cost and thermal property. And if the system uses higher power LED, there must have better thermal disseminate path to eneure long term reliability.

关 键 词：光电子 热阻 正向电压法 功率发光二极管 

分 类 号：TN312.8[电子电信—物理电子学]