| 研究生: |
吳東叡 Wu, Tong-Jui |
|---|---|
| 論文名稱: |
利用奈米柱結構增強白光發光二極體發光效率之研究 Light Extraction Improvement of White Light-Emitting-Diodes using Nanorod Array |
| 指導教授: |
李清庭
Lee, Ching-Ting 賴韋志 Lai, Wei-Chih |
| 學位類別: |
碩士 Master |
| 系所名稱: |
理學院 - 光電科學與工程研究所 Institute of Electro-Optical Science and Engineering |
| 論文出版年: | 2011 |
| 畢業學年度: | 99 |
| 語文別: | 中文 |
| 論文頁數: | 65 |
| 中文關鍵詞: | 水熱法成長 、遠端塗佈 、白光發光二極體 、氧化鋅 、奈米柱 |
| 外文關鍵詞: | aqueous solution, remote phosphor coating, white light-emitting diodes, zinc-oxide (ZnO), nanorod |
| 相關次數: | 點閱:119 下載:3 |
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本研究結合螢光粉遠端塗佈技術與氧化鋅奈米柱陣列結構於白光發光二極體上,實驗中在氮化鎵藍光發光二極體上方以水熱法成長氧化奈米柱陣列,分別覆蓋上矽膠與螢光粉,並藉此改善白光發光二極體的色彩分佈之均勻度、白光轉換效率與元件光輸出功率。此外,元件發光之光場分佈因氧化鋅奈米柱結構之光導向,而有朝垂直元件頂部方向增強的情形。藉由積分球光功率量測系統分析元件的電激發光強度,發光二極體藍光(450 nm)與螢光粉黃光波段(520~600 nm)的發光強度,也因氧化鋅奈米柱結構成長而同時增強。而元件發光之CIE色度座標位於(0.328, 0.335),接近純白光(0.33, 0.33)之位置。另一方面,當同樣使用遠端螢光粉塗佈LED元件操作20毫安培下,具奈米柱結構之白光發光二極體比起未成長奈米柱的白光發光二極體,其螢光粉轉換效率改善了4.5%,而當光輸出功率也增強了9.2%。
In this work, both the remote phosphor coating technique and the zinc-oxide (ZnO) nanorod array were simultaneously used to improve the color uniform distribution, converted efficiency and the light extraction efficiency of white LEDs. Moreover, light output could be enhanced in the vertical direction by the light guidance of the ZnO nanorod array. In the electroluminescence (EL) light measurement, the emission peak of LEDs at 450 nm and the emission band of phosphor at 520~600 nm could be enhanced at the same time. Therefore, the CIE chromaticity coordinate located at (0.328, 0.335), which closed to the pure white light (0.33, 0.33), was obtained. Moreover, the white LED with nanorod array was a 4.5% improvement in phosphor efficiency compared with the remote phosphor coating white LEDs without nanorod, and the light output power was increased 9.2% at 20 mA as well.
[1] N. Holonyak, Jr. and S. F. Bevaqua, “Coherent(visible) Light Emission From Ga(As1–xPx) Junctions,” Appl. Phys. Lett. 1, 82-83 (1962).
[2] S. Nakamura, and G. Fasol, The Blue Laser Diode: GaN based light emitters and lasers (Spinger, Berlin, 1997).
[3] Y. Shimizu, K. Sakano, Y. Noguchi, and T. Moriguchi, “Light emitting device having a nitride compound semiconductor and a phosphor containing a garnet fluorescent material,” United States Patent, US 5998925 (1999).
[4] S. Nakamura, T. Mukai, and M. Senoh, “Candela-class high-brightness InGaN/AlGaN double-heterostructure blue-light-emitting diodes,” Appl.Phys. Lett. 64, 1687-1689 (1994).
[5] A. A. Stelur, A. M. Srivastava, H. A. Comanzo and D. D. Doxsee “Phosphor Blends for Generating White Light from Near-UV/Blue Light-Emitting Devices,” United States Patent, US 6685852 B2 (2004).
[6] T. Yalima, Phosphors Global Summit, San Diego, CA USA (2005).
[7] T. F. McNulty, D. D. Doxsee and J. W. Rose “UV reflector and UV-based Light Source Having Reduced UV Radiation Leakage Incorporating The Same,” United States Patent, Us 6686676 B2 (2004).
[8] A. Zauskas, F. Ivanauskas, R. Vaicekauskas, M. S. Shur and R. Gaska, “Optimization of mulitichip white solid state lighting source with four or more LEDs,” Proc. SPIE 4445, 148-155 (2001).
[9] S. J. Duclos, J. Jansma, J. C. Bortscheller, R. J. Wojnarowski, “Phosphor Coating with Self-adjusting Distance from LED Chip,” United States Patent, US 6635363 B1 (2003).
[10] N. Narendran, Y. Gu, J. P. Freyssinier-Nova, and Y. Zhu, “Extracting phosphor-scattered photons to improve white LED efficiency,” Phys. Statu Solidi A-Appl. Mat., 202, R60-R62 (2005).
[11] D. Y. Kang, E. Wu, and D. M. Wang, “Modeling white light-emitting diodes with phosphor layers,” Appl. Phys. Lett., 89, 231102-1-231102-3 (2006).
[12] Y. Zhu and N. Narendran, “Optimizing the performance of remote phosphor LEDs,” J. Light & Vis. Env., 32, 115-119 (2008).
[13] K. Li and C. Shen, “White light LED based on YAG:Ce3+ and YAG:Ce3+,Gd3+ phosphor”, 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optoelectronic Materials and Devices for Detector, Imager, Display, and Energy Conversion Technology, Dalian, China, 76583K-1-76583K-6 (2008).
[14] E. F. Schubert, Light Emitting Diodes, Cambridge University Press, Cambridge (2003).
[15] 郭浩中、賴芳儀、郭守義, LED原理與應用 (五南圖書出版公司,2009)。
[16] 劉如熹、王健源, 白光發光二極體製作技術 (全華科技圖書公司,2005)。
[17] P. Goldberg, Luminescence of Inorganic Solids; Academic Press: New York, (1966).
[18] D. A. Skoog and J. J. Leary, Principles of Instrumental Analysis-5th ed.; Harcourt Brace College Pub. (1998).
[19] N. R. Taskar, R. N. Bhargava, J. Barone, V. Chhabra, V. Chabra, D.Dorman, A. Ekimov, S. Herko, and B. Kulkarni, “Quantum-confined-atom-based nanophosphors for solid state lighting,” Proc. SPIE 5187, 133-141 (2004).
[20] R. Mueller-Mach, G. Mueller, M. Krames, and T. Trottier, “High-power Phosphor-converted Light-emitting diodes based on III- Nitrides,” IEEE J. Sel. Topics Quantum Electron., 8, 339-345 (2002).
[21] R. Mueller-Mach, G. O. Mueller, and M. R. Krames, “Phosphor materials and combinations for illumination-grade white pcLEDs,” Proc. SPIE 5187, 115-122 (2004).
[22] D. B. Thompson, J. J. Richardson, S. P. DenBaars, and F. F. Lange, “Light emitting diodes with ZnO current spreading layers deposited from a low temperature aqueous solution,” Appl. Phys. Exp., 2, 042101-1-042101-3 ( 2009).
[23] M. K. Lee, C. L. Ho, and P. C. Chen, “Light extraction efficiency enhancement of GaN blue LED by liquid-phase-deposited ZnO rods,” IEEE Photon. Technol. Lett., 20, 252-254 (2008).
[24] K. K. Kim, S. D. Lee, H. Kim, J. C. Park, S. N. Lee, Y. Park, S. J. Park, and S. W. Kim, “Enhanced light extraction efficiency of GaN-based light-emitting diodes with ZnO nanorod arrays grown using aqueous solution,” Appl. Phys. Lett., 94, 071118-1-071118-3 (2009).
[25] R. W. G. Hunt, Measuring colour-2nd ed.; Ellis Horwood: London (1995).
[26] F. A. Jenkins and H. E. White, Fundamentals of Optics, 4th ed., McGraw-Hill Companies, New York, (1976).
[27] H. Luo, J. K. Kim, E. F. Schubert, J. Cho, C. Sone, and Y. Park, “Analysis of high-power packages for phosphor-based white-light-emitting diodes”, Appl. Phys. Lett., 86, 243505-1-243505-3, (2005).