Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/4040
標題: 背金反射鏡對氮化鎵發光二極體特性之影響研究
Effects of Backside Metal Reflectors on Performace of GaN Light-Emitting Diodes
作者: 李長信
Li, Chang-hsin
關鍵字: GaN
氮化鎵
light-emitting diode (LED)
adhesive layer
backside reflector
plasma clean
發光二極體
附著層
晶背反射鏡
電漿清洗
出版社: 精密工程學系所
引用: [1] E. Fred Schubert, “Light-Emitting Diodes,” Cambridge University Press. pp. 1-19, 2003 [2] G. B. Stringfellow, “High brightness light emitting diode,” Academic Press Inc. Boston, pp. 149-219, 1997. [3] S. Nakamura, and Shigefusa F. Chichibu, “Introduction to Nitride Semiconductor Blue Lasers and Light Emitting Diodes,” Taylor & Francis.London, pp. 1-2, 2000 [4] D. S. Wuu, W .K. Wang, W. C. Shih, R. H. Horng, C. E. Lee, W. Y. Lin, and J. S. Fang, “Enhanced output power of near-ultraviolet InGaN - GaN LEDs grown on patterned sapphire substrates,” IEEE Photon. Technol. Lett., vol. 17, pp. 288-290, Feb. 2005. [5] C. S. Chang, S. J. Chang, Y. K. Su, C. T. Lee, Y. C. Lin, W. C. Lai, S. C. Shei, J. C. Ke, and H. M. Lo, “Nitride-Based LEDs With Textured Side Walla,” IEEE Photon. Technol. Lett., vol. 16, pp. 750-752, 2004. [6] J. Baur, B. Hahn, M. Fehrer, D. Eisert, W. Stein, A. Plossl, F. Kuhn, H. Zull, M. Winter, and V. Harle, “InGaN on SiC LEDs for High Flux and High Current Applications,” Phys. Stat. Sol. vol. 194, pp. 399-402, 2002. [7] S. Nagahama, N. Iwasa, M. Senoh, T. Matsushita, Y. Sugimoto, H. Kiyoku, T. Kozaki, M. Sano, H. Matsumura, H. Umemoto, K. Chocho, T. Yanamoto, and T. Mukai, “GaN-Based Light-Emitting Diodes and Laser Diodes, and Their Recent Progress,” Phys. Stat. Sol. vol. 188, pp. 1-7, 2001 [8] T. Fujii, Y. Gao, R. Sharma, E. L. Hu, S. P. DenBaars, and S. Nakamura, “Increase in the extraction efficiency of GaN-based light-emitting diodes via surface roughening,” App. Phys. Lett., vol. 84, pp. 855-857, 2004. [9] J. J. Wierer, D. A. Steigerwald, M. R. krames, J. J. O’Shea, M. J. Ludowise, G. Christenson, Y. C. Shen, C. Lowery, P. S. Martin, S. Subramanya, W. Gotz, N. F. Gardner, R. S. Kern, and S. A. Stockman, “High-power AlGaInN flip-chip light-emitting diodes,” App. Phys. Lett., vol. 78, pp. 3379-3381, May. 2001. [10] S. M. Sze, “Semiconductor Devices Physici and Technology,” 2nd Edition, Wiley, Taiwan, pp.88-92, 2001. [11] D. A. Neamen, “Semiconductor physics & devices:basic principles,” Third Edition, McGraw-Hill, pp. 268-275. 2002. [12] 史光國, “現代半導體發光及雷射二極體材料技術,” 全華科技,台北,台灣, pp, 4-1~4-10, 2001. [13] 耿繼業, 何建娃, “幾何光學,”全華科技, 台北, 台灣, pp.38-49, 2001. [14] 李正中, “薄膜光學與鍍膜技術,” 第五版, 藝軒出版社, 台北, 台灣, pp.143-176, 2006. [15] 李秉璋, 王正和, “金屬反射膜材料簡介,” 工業材料168期, pp. 125-130, 2000. [16] S. M. Pan, R. C. Tu, Y. M. Fan, R. C. Yeh, and J. T. Hsu, “Enhanced Output Power of InGaN–GaN Light- Emitting Diodes With High-Transparency Nickel-Oxide–Indium- Tin -Oxide Ohmic Contacts,” IEEE Photon. Technol. Lett., vol. 15, pp. 646-648, May. 2003. [17] W. F. Smith, “Foundations of Materials Science and Engineering,” Third Edition, McGraw-Hill, pp.6-13 . 2004. [18] 柯賢文, “表面與薄膜處理技術,” 全華科技, 台北, 台灣, pp. 3-1~3-11, 2005. [19] 白木靖寬, 吉田貞史 編著, 王建義 編譯, “薄膜工程學,” 全華科技,台北, 台灣, pp. 4-32~4-38, 2004.
摘要: 本論文之主要研究動機是利用金屬鋁的高反射率,將氮化鎵(GaN)發光二極體向下發射的光反射,進而增加發光二極體外部量子效率。而在藍寶石基板上,背鍍金屬鋁會產生附著力不良,容易造成金屬鋁脫落。因此,必須藉由蒸鍍一層薄膜當作附著層,以增加藍寶石基板與金屬鋁的黏著性,其結構為氮化鎵/藍寶石/附著層/金屬鋁反射鏡,但是,由於增加附著層會使反射的光有所衰減,因此必須再提升亮度與增加附著力之間,找出最佳的平衡點。在實驗中我們將選用鎳/鋁、鈦/鋁、鉻/鋁及二氧化矽/鋁作為不同的反射鏡。 在量測元件之附著力、光電特性及封裝後之輸出功率,證明實驗中氮化鎵/藍寶石/鎳/鋁結構提升23.7 %的發光強度,氮化鎵/藍寶石/鈦/鋁結構提升28.6 %的發光強度,氮化鎵/藍寶石/鉻/鋁結構提升20.8 %的發光強度,而附著力皆有明顯改善。此外,也可以藉由在晶片清洗後加打電漿清除(Plasma Stripper)的方式,可將鋁膜降低脫落比例至0.1 %,此種製程方式,不僅不會有附著層吸光而降低反射率的問題,在光電特性中的表現也是最好的(提升44%的發光強度)。因此,本實驗提供了增加附著層及增加電漿清除等方式,解決藍寶石基板背鍍金屬鋁會產生脫落的問題。
The effect of backside aluminum (Al) reflectors on the performance of GaN light-emitting diodes (LEDs) was investigated in this thesis. For a typical chip process line, the backside Al coating on a sapphire substrate can enhance the external quantum efficiency except the poor adhesion problem. After the chip dicing process, the Al films can be peeled off by the blue tape easily. Therefore, it is necessary to insert a proper adhesive layer between Al and sapphire or incorporating an additional cleaning process. However, the adhesive layer such as Ti or Cr will sacrifice the reflectivity of the backside mirror. In this study, various backside mirror structures (e.g. Ni/Al, Ti/Al, Cr/Al, and SiO2/Al) for the GaN/sapphire green LEDs were attempted. However, the SiO2 interlayer can not solve the adhesion problem in our experiments. It was found that a comprise should be made between the metallic interlayer thickness and output power. As compared with the original GaN LED without a backside mirror, the samples with the backside Ni/Al, Ti/Al and Cr/Al reflectors show 23.7, 28.6 and 20.8% improvement in output power, respectively. On the other hand, the adhesion between Al and sapphire is found to be greatly improved and the peeling ratio can be reduced to 0.1% by incorporating a plasma clean process before the Al evaporation. It provides not only higher adhesion property but also the best LED performance (44% enhancement in luminance intensity).
URI: http://hdl.handle.net/11455/4040
其他識別: U0005-0502200701291500
文章連結: http://www.airitilibrary.com/Publication/alDetailedMesh1?DocID=U0005-0502200701291500
Appears in Collections:精密工程研究所

文件中的檔案:

取得全文請前往華藝線上圖書館

Show full item record
 
TAIR Related Article
 
Citations:


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.