-
基于电流连续方程、欧姆定律及定性三维热流传导模型研究发光二极管(LED)芯片 的电流密度分布、热量、温度之间的相互交叉关系,进而测试分析GaN基蓝光 LED电流扩展效应和亮度分布的关系,认为芯片亮度变化趋势可作为判别电流扩 展性能的有效手段. 由于芯片表面温度、亮度分布和电流密度之间存在紧密的联结 关系,通过测试芯片表面温度或亮度分布就可定性了解器件电流扩展性能, 从而为优化电极结构提供一种判定依据. 在不同电流和热沉温度下,进一步 讨论了电流密度非均匀性和亮度分布的关系, 电流密度拥挤将导致芯片局 部区域热量堆积,非辐射复合作用增强,限制出射光子数目, 因此热 量是影响亮度分布的重要因素之一. 通过载流子传输机理进一步说明 温度影响亮度均匀性的原因,并通过实验说明理论分析的可行性. 通过优化电极结构能改善器件的电流扩展效应以及亮度均匀性, 对提高大功率LED的可靠性具有重要作用.In this paper, we study the relationship among current density distribution, heat and temperature based on current continuity equation, ohm law and three-dimensional heat transfer model. The relationship between luminance distribution and current spreading of GaN blue light emitting diode (LED) is studied. Luminance distribution is proved to be an effective method of distinguishing the performance of current spreading. Because of the close relationship among temperature, luminance distribution and current density, a qualitative method of optimizing electrode structure and current spreading is proposed. With different currents and heat sink temperatures, the current non-uniformity and the luminance distribution of LED are analyzed. Temperature or current density crowding results in heat accumulation, increase of non-radiative recombination and the restriction of the emitting photons, hence thermal flux is an important factor influencing the luminance distribution. Through carrier transport mechanism, the reason for the temperature influence on luminance distribution is explained. Optimized contact electrode structure can improve current spreading and luminance uniformity, also considerably increase the reliability of high power LED.
-
Keywords:
- light emitting diode /
- current spreading /
- luminance uniformity /
- temperature distribution
[1] Kim H S, Lee J M, Huh C, Kim S W, Kim D J, Park S J, Hwang H S 2000 Appl. Phys. Lett. 77 1903
[2] Chen H T, Tao X H, Hui S Y R 2012 IEEE Trans. Power Electron. 27 2176
[3] Li P L, Wang Z J, Yang Z P, Guo Q L 2011 Acta Phys. Sin. 60 047804 (in Chinese) [李盼来,王志军,杨志平,郭庆林 2011物理学报 60 047804]
[4] Shen G D, Zhang J M, Zou D S, Xu C, Gu X L 2008 Acta Phys. Sin. 57 472 (in Chinese) [沈光地,张剑铭,邹德恕,徐晨,顾晓铃 2008 物理学报 57 472]
[5] Pan H P, Huang L W, Li R, Lin L, Chen Z Z, Zhang G Y, Hu X D 2007 Chin. J. Lumines. 28 114 (in Chinese) [潘华璞, 黄利伟, 李 睿, 林 亮, 陈志忠, 张国义, 胡晓东 2007 发光学报 28 114]
[6] Deng Y L, Liao C J, Liu S H, Fan G H, Wen S S 2002 Chin. J. Lumines. 23 255 (in Chinese) [邓云龙, 廖常俊, 刘颂豪, 范广涵, 文尚胜 2002 发光学报 23 255]
[7] Hwang S, Shim J 2008 IEEE Trans. Electron Dev. 55 1123
[8] Guo X, Schubert E F 2001 Appl. Phys. Lett. 78 3337
[9] Kim H, Park S J, Hwang H 2002 Appl. Phys. Lett. 77 1903
[10] Chen H T, Lü Y J, Chen Z, Zhang H B, Gao Y L, Chen G L 2009 Acta Phys. Sin. 58 5700 (in Chinese) [陈焕庭,吕毅军, 陈忠,张海兵,高玉琳,陈国龙 2009 物理学报 58 5700]
[11] Huang S J, Wu H, Fan B F, Zhang B J, Wang G 2010 J. Appl. Phys. 107 054509
[12] Zhao Y G, Mcinerney J G 1996 IEEE J. Quantum Electron 32 1950.
[13] Zhang Y Y, Fan G H 2011 Acta Phys. Sin. 60 078504 (in Chinese) [张运炎, 范广涵 2011 物理学报 60 078504]
[14] Chen H T, Gao Y L, Lu L J, Chen G L, Chen Z 2012 Heat Transfer Engineering 33 255
[15] Gärditz C, Winnacker A, Schindler F, Paetzold R 2007 Appl. Phys. Lett. 90 103506
[16] Li B Q, Liu Y H, Feng Y C 2008 Acta Phys. Sin. 57 477 (in Chinese) [李炳乾, 刘玉华, 冯玉春 2008物理学报 57 477]
-
[1] Kim H S, Lee J M, Huh C, Kim S W, Kim D J, Park S J, Hwang H S 2000 Appl. Phys. Lett. 77 1903
[2] Chen H T, Tao X H, Hui S Y R 2012 IEEE Trans. Power Electron. 27 2176
[3] Li P L, Wang Z J, Yang Z P, Guo Q L 2011 Acta Phys. Sin. 60 047804 (in Chinese) [李盼来,王志军,杨志平,郭庆林 2011物理学报 60 047804]
[4] Shen G D, Zhang J M, Zou D S, Xu C, Gu X L 2008 Acta Phys. Sin. 57 472 (in Chinese) [沈光地,张剑铭,邹德恕,徐晨,顾晓铃 2008 物理学报 57 472]
[5] Pan H P, Huang L W, Li R, Lin L, Chen Z Z, Zhang G Y, Hu X D 2007 Chin. J. Lumines. 28 114 (in Chinese) [潘华璞, 黄利伟, 李 睿, 林 亮, 陈志忠, 张国义, 胡晓东 2007 发光学报 28 114]
[6] Deng Y L, Liao C J, Liu S H, Fan G H, Wen S S 2002 Chin. J. Lumines. 23 255 (in Chinese) [邓云龙, 廖常俊, 刘颂豪, 范广涵, 文尚胜 2002 发光学报 23 255]
[7] Hwang S, Shim J 2008 IEEE Trans. Electron Dev. 55 1123
[8] Guo X, Schubert E F 2001 Appl. Phys. Lett. 78 3337
[9] Kim H, Park S J, Hwang H 2002 Appl. Phys. Lett. 77 1903
[10] Chen H T, Lü Y J, Chen Z, Zhang H B, Gao Y L, Chen G L 2009 Acta Phys. Sin. 58 5700 (in Chinese) [陈焕庭,吕毅军, 陈忠,张海兵,高玉琳,陈国龙 2009 物理学报 58 5700]
[11] Huang S J, Wu H, Fan B F, Zhang B J, Wang G 2010 J. Appl. Phys. 107 054509
[12] Zhao Y G, Mcinerney J G 1996 IEEE J. Quantum Electron 32 1950.
[13] Zhang Y Y, Fan G H 2011 Acta Phys. Sin. 60 078504 (in Chinese) [张运炎, 范广涵 2011 物理学报 60 078504]
[14] Chen H T, Gao Y L, Lu L J, Chen G L, Chen Z 2012 Heat Transfer Engineering 33 255
[15] Gärditz C, Winnacker A, Schindler F, Paetzold R 2007 Appl. Phys. Lett. 90 103506
[16] Li B Q, Liu Y H, Feng Y C 2008 Acta Phys. Sin. 57 477 (in Chinese) [李炳乾, 刘玉华, 冯玉春 2008物理学报 57 477]
计量
- 文章访问数: 7187
- PDF下载量: 765
- 被引次数: 0