1. NCHU Institution Repository
  2. 工學院
  3. 材料科學與工程學系
Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/10289
標題: Improved Performance of AlGaInP Light-Emitting Diodes Using Various Process Techniques
高功率磷化鋁鎵銦發光二極體特性提升之製程研究
作者: Hsu, Shun-Cheng
許順成
關鍵字: lGaInP;磷化鋁鎵銦;light-emitting diode (LED);indium-tin oxide (ITO);omni-directional reflector (ODR);current-spreading layer;textured surface;發光二極體;氧化銦鍚;全反射角的高反射鏡面;電流分佈層;粗化表面
出版社: 材料科學與工程學系所
引用: [1] N. Holonyak, Jr. and S. F. Bevacqua, “Coherent (visible) light emission from Ga(As1-xPx) junctions,” Appl. Phys. Lett., vol. 1, pp. 82-83, 1962. [2] R. A. Logan, H. G. White and W. Wiegmann, “Efficient green electroluminescence in nitrogen-doped GaP p-n junctions,” Appl. Phys. Lett., vol. 13, pp. 139-141, 1968. [3] Zh. I. Alferov, V. M. Andreev, D. Z. Garbuzov and V. D. Rumyantsev, “Internal quantum efficiency (100per cent) of radiative recombination in three-layer AlAs-GaAs heterojunction light-emitting diodes,” Sov. Phys. Semicond., vol. 9, pp. 305-309, 1975. [4] C. P. Kuo, R. M. Fletcher, T. D. Osentowski, M. C. Lardizabal, M. G. Craford, and V. M. Robbins, “High performance AlGaInP visible light emitting diodes,” Appl. Phys. Lett., vol. 57, pp. 2937-2939, 1990. [5] H. Sugawara, M. Ishikawa, and G. Hatakoshi, “High-efficiency InGaAlP/GaAs visible light-emitting diodes,” Appl. Phys. Lett., vol. 58, pp. 1010-1012, 1991. [6] C. H. Chen, S. A. Stockman, M. J. Peanasky, and C. P. Kuo, “OMVPE growth of AlInGaP for high-efficiency visible light emitting diodes,” Semiconduct Semimet, vol. 48, pp. 97-99, 1997. [7] T. Kato, H. Susawa, M. Hirotani, T. SaKa, Y. Ohashi, E. Shichi, and S. Shibata, “GaAs/AlGaAs surface emitting IR LED with bragg reflector grown by MOCVD,” J. Cryst. Growth., vol. 107, pp. 832-835, 1991. [8] F. A. Kish, F. M. Steranka, D. C. DeFevere, D. A. Vanderwater, K. G. Park, C. P. Kuo, T. D. Osentowski, M. J. Peanasky, J. G. Yu, R. M. Fletcher, D. A. Steigerwald and M. G. Craford, “Very high-efficiency semiconductor wafer-bonded transparent-substrate (AlxGa1−x)0.5In0.5P/GaP light-emitting diodes,” Appl. Phys. Lett., vol. 64, pp. 2839-2841, 1994. [9] M. R. Krames, M. O. Holcomb, G. E. Höfler, C. C. Coman, E. I. Chen, I. H. Tan, P. Grillot, N. F. Gardner, H. C. Chui, J. W. Huang, S. A. Stockman, F. A. Kish, M. G. Craford, T. S. Tan, C. P. Kocot, M. Hueschen, J. Posselt, B. Loh, G. Sasser, and D. Collins, “High-power truncated-inverted-pyramid (AlxGa1-x)0.5In0.5P/GaP light-emitting diodes exhibiting >50% external quantum efficiency,” Appl. Phys. Lett., vol. 75, pp. 2365-2367, 1999. [10] A. Erchak, D. J. Ripin, S. Fan, P. Rakich, J. D. Joannopoulos, E. P. Ippen,G. S. Petrich, and L. A. Kolodziejski, “Enhanced coupling to vertical radiation using a two-dimensional photonic crystal in a semiconductor light-emitting diode,” Appl. Phys. Lett., vol. 78, pp. 563-565, 2002. [11] R. H. Horng, D. S. Wuu, C. Y. Tseng, M. F. Huang, K. H. Chang, P. H. Liu and K. C. Lin, “AlGaInP light-emitting diodes with mirror substrates fabricated by wafer bonding,” Appl. Phys. Lett., vol. 75, pp. 3054-3056, 1999. [12] K. Streubel, N. Linder, R. Wirth, and A. Jaeger, “High brightness AlGaInP light-emitting diodes ,” IEEE J. Select. Top. Quantum Electron., vol. 8, pp. 321-332, 2002. [13] I. Schnitzer, E. Yablonovitch, C. Caneau, and T. J. Gmitter, “Ultrahigh spontaneous emission quantum efficiency, 99.7% internally and 72% externally, from AlGaAs/GaAs/AlGaAs double heterostructures,” Appl. Phys. Lett., vol. 62, pp. 131-133, 1993. [14] T. Gessmann, E. F. Schubert, J. W. Graff, K. Streubel and C. Karnutsch, “Omnidirectional reflective contacts for light-emitting diodes,” IEEE Electr. Device L., vol. 24, pp. 683-685, 2003. [15] S. M. Sze, Physics of Semiconductor Devices, 2nd edition (John Wiley & Sons, Inc., Canada, 1981). [16] W. F. Wu and B. S. Chiouand, “Properties of radio-frequency magnetron sputtered ITO films without in-situ substrate heating and post-deposition annealing,” Thin Solid Films, vol. 247, pp. 201-207, 1994. [17] Y. S. Jung, “Spectroscopic ellipsometry studies on the optical constants of indium tin oxide films deposited under various sputtering conditions,” Thin Solid Films, vol. 467, pp. 36-42, 2004. [18] R. P. Howson and R.P. Howson, “Use of the magnetron-sputtering technique for the control of the properties of indium tin oxide thin films,” Surf. Coat. Technol., vol. 111, pp. 163-171, 1999 [19] W. Wohlmath and I. Adesida, “Properties of R.F. magnetron sputtered cadmium-tin-oxide and indium-tin-oxide thin films,” Thin Solid Films, vol. 479, pp. 223-231, 1999 [20] D. V. Morgan, Y. H. Aliyu, R. W. Bunce, and A. Salehi, “Annealing effects on opto-electronic properties of sputtered and thermally evaporated indium-tin-oxide films,” Thin Solid Films, vol. 247, pp. 201-207, 1998. [21] T. Ishida, H. Kobayashi, and Y. Nakato, “Structures and properties of electron-beam-evaporated indium tin oxide films as studied by x-ray photoelectron spectroscopy and work-function measurements,” J. Appl. Phys., vol. 73, pp. 4344-4350, 1993. [22] H. Kobayashi, T. Ishida, K. Nakamura, Y. Nakato, and H. Tsubomura, “Properties of indium tin oxide films prepared by the electron beam evaporation method in relation to characteristics of indium tin oxide/silicon oxide/silicon junction solar cells,” J. Appl. Phys., vol. 72, pp. 5288-5294, 1992. [23] H. J. Krokoszinski and R. Oesterlein, “Post-deposition annealing effects in electron-beam-evaporated indium tin oxide thin films,” Thin Solid Films, vol. 187, pp. 179-186, 1990. [24] T. Maruyama and K.Fukui, “Indium tin oxide thin films prepared by vapor deposition,” Thin Solid Films, vol. 203, pp. 297-302, 1991. [25] T. Maruyama and K. Fukui, “Indium-tin oxide thin films prepared by chemical vapor deposition,” J. Appl. Phys., vol. 70, pp. 3848-3854, 1991. [26] H. Kim, J. S. Horwitz, and G. Kushto, “Effect of film thickness on the properties of indium tin oxide thin films,” J. Appl. Phys., vol. 88, pp. 6021-6025, 2000. [27] J. Ma, S. Y. Li, J. Q. Zhao, and H. L. Ma, “Preparation and properties of indium tin oxide films deposited on polyester substrates by reactive evaporation,” Thin Solid Films, vol. 307, pp. 200-202, 1997. [28] M. J. Alam and D. C. Cameron, “Optical and electrical properties of transparent conductor ITO thin films deposited by sol-gel process,” Thin Solid Films, vol. 377-378, pp. 455-459, 2000. [29] S. S. Kim, S. Y. Choi, C. G. Park, and C. G. Jin, “Transparent conductive ITO thin films through the sol-gel process using metal salts,” Thin Solid Films, vol. 347, pp. 155-160, 1999. [30] L. Meng , A. Macarcio, and R. Martins, “Study of annealed indium tin oxide films prepared by rf reactive magnetron sputtering”, Vacuum, vol. 46, pp 673-680, 1995. [31] S. Uekusa, R. Nakano, and K. Yokogawa, “Post deposition annealing influence on sputtered indium-tin oxide film characteristics”, Jpn. J. Appl. Phys., (l-Regular Papers), Short Notes, vol. 33, pp 302-306, 1994. [32] A. J. Steckl and G. Mohammed, “The effect of ambient atmosphere in the annealing of indium tin oxide films”, J. Appl. Phys., vol. 51, pp 3890-3895, 1980. [33] M. Higuchi, S. Uekusa, R. Nakano, and K. Yokogawa, “Post deposition annealing influence on sputtered indium tin oxide film characteristics”, Jpn. J. Appl. Phys., vol. 33, pp 302-306, 1994 [34] Y. Hosokawa, W. Nabekura, T. Hoshina, R. Takeuchi, K. Sakaue, and T. Udagawa, “High-power ohmic-electrodes dispersive AlGaInP double-hetero structure yellowish-green light-emitting diodes,” J. Cryst. Growth, vol. 221, pp. 652-656, 2000. [35] G. S. Marlow, and M. B. Das, “The effects of contact size and non-zero metal resistance on the determination of specific contact resistance,” Solid State Electron., vol. 25, pp. 91-94, 1981 [36] G. K. Reeves, “Specific contact resistance using a circular transmission line model,” Solid State Electron., vol. 23, pp. 487-490, 1980 [37] D. V. Mogan, Y. H. Aliyu, R. W. Bunch, S. Barren, and T. Boss, “Electrical and optical properties of high performance MOCVD grown (AlxGa1-x)yIn1-yP visible light-emitting diodes,” Electron. Lett., vol. 22, pp. 1991-1992, 1993. [38] R. Wirth, S. Illek, C. Karnutsch, I. Pietzonka, A. Plössl, P. Stauss, W. Stein, W. Wegleiter, R. Windisch, H. Zull, and K. Streube, “Recent progress of AlGaInP thinfilm light emitting diodes,” Proc. SPIE, vol. 4996, pp. 1-9, 2003. [39] D. A. Vanderwater, I. H. Tan, G. E. Hofler, D. C. Defever, and F. A. Kish, “High-brightness AlGaInP light emitting diodes,” Proc. IEEE, vol. 85, pp. 1752-1764, 1997. [40] M. R. Krames, O. B. Shchekin, R. M. Mach, G. O. Mueller, L. Zhou, G. Harbers, and M. G. Craford, “Status and future of high-power light-emitting diodes for solid-state lighting,” IEEE J. Disp. Technol., vol. 3, pp. 160-175, 2007. [41] T. Gessmann and E. F. Schubert, “High-efficiency AlGaInP light-emitting diodes for solid-state lighting applications,” J. Appl. Phys., vol. 95, pp. 2203-2216, 2004. [42] H. Sugawara, K. Itaya, H, Nozaki, and G. Hatakoshi, “High-brightness InGaAlP green light-emitting diodes,” Appl. Phys. Lett., vol. 61, pp. 1775-1777, 1992. [43] K. H. Huang, J. G. Yu, C. P. Kuo, R. M. Fletcher, T. D. Osentowski, L. J. Stinson, M. G. Craford, and A. S. H. Liao, “Twofold efficiency improvement in high performance AlGalnP lightemitting diodes in the 555-620 nm spectral region using a thick GaP window layer,” Appl. Phys. Lett., vol. 61, pp. 1045-1047, 1992. [44] R. M. Fletcher, C. P. Kuo, T. D. Osentowski, K. H. Huang, M. G. Craford, and V. M. Robbins, “The growth and properties of high performance AlGaInP emitters using a lattice mismatched GaP window layer,” J. Electron. Mater., vol. 20, pp. 1125-1130, 1991. [45] L. B. Chang, P. Y. Kuei, L. Z. Hsieh, L. Y. Chang, and R. M. Lin., “Study of AIGaInP multiquantum-well/double heterostructure light-emitting diodes with in-added GaP window layer regrown by antimony-based liquid phase epitaxy,” J. Vac. Sci. Technol. A., vol. 22, pp. 807-810, 2004. [46] C. Y. Lee, M. C. Wu, and W. Lin, “The influence of window layers on the performance of 650 nm AlGaInP/GaInP multi-quantum-well light-emitting diodes,” J. Cryst. Growth., vol. 200, pp. 382-390, 1999. [47] J. F. Lin, M. C. Wu, M. J. Jou, C. M. Chang, B. J. Lee, and Y. T. Tsai, “Highly reliable operation of indium tin oxide AlGaInP orange light-emitting diodes,” Electron. Lett., vol. 30, pp. 1793-1794, 1994. [48] D. V. Morgan, I. M. Al-Ofi, and Y. H. Aliyu, “Indium tin oxide spreading layers for AlGaInP visible LEDs,” Semicond. Sci. Tech., vol. 15, pp. 67-72, 2000. [49] S. C. Hsu, D. S. Wuu, C. Y. Lee, J. Y. Su, and R. H. Horng, “High-efficiency 1-mm2 AlGaInP LEDs sandwiched by ITO omni-directional reflector and current-spreading layer,” IEEE Photon. Technol. Lett., vol. 19, pp. 492-494, 2007. [50] H. C. Wang, Y, K. Su, C. L. Lin, W. B. Chen, S. M. Chen, and W. L. Li, “Improvement of AlGaInP multiple-quantum-well light-emitting diodes by modification of ohmic contact layer,” Jpn. J. Appl. Phys., vol. 43, pp. 1934-1936, 2004. [51] Y. H. Aliyu, D. V. Morgan, H. Thomas, and S. W. Bland. “AlGaInP LEDs using reactive thermally evaporated transparent conducting indium tin oxide (ITO),” Electron. Lett., vol. 30, pp. 2210-2212, 1995. [52] H. C. Wang, Y. K. Su, C. L. Lin, W. B. Chen, and S. M. Chen, “Improvement of AlInP-AlGaInP MQW light-emitting diode by meshed contact layer,” IEEE Photonics Technol. Lett., vol. 14, pp. 1491-1493, 2002. [53] S. C. Jain, J. M. McGregor, and D. J. Roulston, “Band-gap narrowing in novel III-V semiconductors,” J. Appl. Phys., vol. 68, pp. 3747-3749, 1990. [54] D. J. Lawrence, D. C. Abbas, D. J. Phelps, and F. T. J. Smith, “GaAs0.6P0.4 LED's with efficient transparent contacts for spatially uniform light emission,” IEEE Trans. Electron Devices, vol. ED-30, pp. 580-585, 1983. [55] Y. Fink, J. N. Winn, S. Fan, C. Chen, J. Michel, J. D. Joannopoulos, and E. L. Thomas, “A dielectric omnidirectional reflector,” Science, vol. 282, pp. 1679-1682, 1998. [56] M. F. Weber, C. A. Stover, L. R. Gilbert, T. J. Nevitt, and A. J. Ouderkirk, “Giant birefringent optics in multilayer polymer mirrors,” Science, vol. 287, pp. 2451-2456, 2000. [57] A. A. Erchak, D. J. Ripin, S. Fan, P. Rakich, J. D. Joannopulos, E. P. Ippen, G. S. Petrich, and L. A. Kolodziejski, “Enhanced coupling to vertical radiation using a two-dimensional photonic crystal in a semiconductor light emitting diode,” Appl. Phys. Lett., vol. 78, pp. 563-565, 2001. [58] J. K. Kim, T. Gessmann, H. Lou, and E. F. Schubert, “GaInN light-emitting diodes with RuO2/SiO2/Ag omni-directional reflector,” Appl. Phys. Lett., vol. 84, pp. 4508-4510, 2004. [59] S. Jang, B. S. Kang, F. Ren, N. W. Emanetoglu, H. Shen, W. H. Chang, B. P. Gila, M. Hlad, and S. J. Pearton, “Surface characterization and microstructure of ITO thin films at different annealing temperature,” J. Electrochem. Soc., vol. 154, pp. H336-H339, 2007. [60] F. Matino, L. Persano, V. Arima, D. Pisignano, R. I. Blyth, R. Cingolani, and R. Rinaldi, “Electronic structure of indium-tin-oxide films fabrication by reactive electron beam,” Phys. Rev. B, vol. 72, pp. 085437-085442 , 2005. [61] D. Raoufi, A. Kiasatpour, H. R. Fallah, and A. S. H. Rozatian, “Comparison of e-beam and sputter-deposited ITO films for 1.55 μm metal-semiconductor-metal photodetector applications,” Appl. Surf. Sci., vol. 253, pp. 9085-9090, 2007. [62] C. Rooman, M. Kuijk, S. De Jonge, and P. Heremans, “High-efficiency AlGaInP thin-film LEDs using surface-texturing and wafer bonding with conductive epoxy,” IEEE Photon. Technol. Lett., vol. 17, pp. 2649-2651, 2005. [63] C. E. Lee; H. C. Kuo; Y. C. Lee; M. R. Tsai, T. C. Lu, S. C. Wang, and C. T. Kuo, “Luminance enhancement of flip-chip light-emitting diodes by geometric sapphire shaping structure ,” IEEE Photon. Technol. Lett., vol. 20, pp. 184-186, 2008 [64] S. J. Chang and Y. K. Su, “AlGaInP-sapphire glue bonsed light-emitting diodes”, IEEE J. Quantum Elect., Vol. 38, pp.1390-1394, 2002. [65] R. H. Horng, D. S. Wuu, C. H. Seieh, W. C. Peng, M. F. Huang, S. J. Tsai, andJ. S. Liu, “Wafer bonding of 50-mm-diameter mirror substrates to AlGaInP light-emitting diodes wafers,” J. Electron. Mater., Vol. 30, pp. 907-910, 2001. [66] C. Rooman, M. Kuijk, S. De Jonge, and P. Heremans, “High-efficiency AlGaInP thin-film LEDs using surface-texturing and wafer bonding with conductive epoxy,” IEEE Photon. Technol. Lett., vol. 17, pp. 2649-2651, 2005. [67] Y. J. Lee, H. C. Tseng, H. C. Kuo, S. C. Wang, C. W. Chang, T. C. Hsu, Y. L. Yang, M. H. Hsieh, M. J. Jou, and B. J. Lee, “Improvement in light-output efficiency of AlGaInP LEDs fabricated on stripe patterned epitaxy,” IEEE Photon. Technol. Lett., vol. 17, pp. 2532-2534, 2005 [68] I. Schnitzer, E. Yablonovitch, C. Caneau, and T. J. Gmitter, “30% external quantum efficiency from surface textured, thin-film light-emitting diodes,” Appl. Phys. Lett., vol. 63, pp. 2174-2176, 1993. [69] R. Windisch, B. Dutta, M. Kuijk, A. Knobloch, S. Meinlschmidt, S. Schoberth, P. Kiesel, G. Borghs, G. H. Döhler, and P. Heremans, “40% efficient thin-film surface-textured light-emitting diodes by optimization of natural lithography,” IEEE Trans. Electron Devices, vol. 47, pp. 1492-1498, 2000. [70] N. Linder, S. Kugler, P. Stauss, K. P. Streubel, R. Wirth and H. Zull, “High-brightness AlGaInP light-emitting diodes using surface texturing,” Proc. SPIE, vol. 4278, pp. 19-25, 2001. [71] R. Windisch, C. Rooman, S. Meinlschmidt, P. Kiesel, D. Zipperer, G. H. Döhler, B. Dutta, M. Kuijk, G. Borghs and P. Heremans “Impact of texture-enhanced transmission on high-efficiency surface-textured light-emitting diodes,” Appl. Phys. Lett., vol. 79, pp. 2315-2317, 2001. [72] M. Boroditsky, T. F. Krauss, R. Coccioli, R. Vrijen, R. Bhat and E. Yablonovitch “Light extraction from optically pumped light-emitting diode by thin-slab photonic crystals,” Appl. Phys. Lett., vol. 75, pp. 1036-1038, 1999. [73] M. D. B. Charlton, M. E. Zoorob and T. Lee “Photonic quasi-crystal LEDs: design, modelling, and optimisation,” Proc. of SPIE, vol. 6486, pp. 64860R [74] Th. Gessmann, E. F. Schubert, J. W. Graff, and K. P. Streubel, “AlGaInP light-emitting diodes with omni-directionally reflecting submount,” Proc. SPIE, vol. 4996, pp. 26-39, 2003 [75] Y. Hosokawa, W. Nabekura, T. Hoshina, R. Takeuchi, K. Sakaue and T. Udagawa, “High-power ohmic-electrodes dispersive AlGaInP double-hetero structure yellowish-green light-emitting diodes,” J. Crystal Growth, vol. 221, pp. 652-656, 2000.
摘要: 
近年來，化合物半導體的研究及應用更是受到各界的矚目，也是當前國家所要全力推動的重點科技項目之一。其中以大量地應用在通訊，照明，交通等方面之磷化鋁鎵銦發光二極體(AlGaInP light-emitting diode)為大家所熟知，其發出的光波段則介於可見光區中的紅~黃綠光區。
本論文，設計一些新的發光二極體製作方法，以提高發光效率。描述如下：
(一) 成功製作具有全反射角的高反射鏡面(omni-directional reflector; ODR)結構與氧化銦鍚電流分佈層的大尺寸垂直發光二極體。其中ODR結構包含p型磷化鎵、分散式的金鈹合金當歐姆接觸點、低折射率的中間層氧化銦鍚及金屬層銀。並且將散熱矽基板黏貼至具有ODR反射鏡面的發光二極體上。ODR反射鏡面發光二極體在650 mA時，產生最大輸出功率304 mW，而外部量子文效率在100 mA時，可達到31.8 %，這是因為具有全反射角的高反射鏡面所造成的。
(二) 利用具全反射角的高反射鏡面結構之四元發光二極體(具散熱矽基板)，來製作具表面粗化之高功率發光二極體，由於粗化表面，這樣更能將高功率發光二極體的亮度大幅提升。二維波浪粗化結構是利用黃光及非等向性蝕刻技術製造而成。粗化結構雖然因為電流堵塞造成順向電壓輕微上升，但是輸出功率在350 mA時，較沒有粗化結構增加 40%。
(三) 我們利用氧化銦鍚(indium tin oxide; ITO)當電流分佈層及歐姆接觸層，增加發光二極體電流均勻分佈能力，鍍在具有高濃度碳摻雜的磷化鎵接觸層之四元發光二極體(具砷化鎵吸收基板)，以提高發光亮度。而外部量子文效率在20 mA時，可達3.24 %，比不具有GaP:C/ITO結構高出70 %的效率。

Recently, the research and application of compound semiconductors are more look at attentively and are also one of the focal technical items that Taiwan industry wants to develop. Among them, the AlGaInP light-emitting diode (LED) applied on large scale in communication, illumination, traffic lamps, etc has been know very well where its luminescence wavelength covers from red to yellow-green between visible optical spectra.
In this dissertation, we have developed several fabrication processes to improve the light output of the AlGaInP LED. First, a 1-mm2 AlGaInP LED sandwiched by ITO omni-directional reflector (ODR) and current-spreading layer is presented. The vertical-conducting bottom ODR consists of p-GaP, dispersive dot-contacts of Au/AuBe/Au acting as ohmic contacts, an intermediate low-refractive-index layer of indium-tin-oxide (ITO), and a silver layer. A Si substrate, which acted as a heat sink, was bonded to the ODR-covered LED structure using a metal-to-metal bonding process. The maximum output power of the ODR-LED was 304 mW at 650 mA, and the output power did not saturate up to a 650-mA injection current. An external quantum efficiency of 31.8% at 100 mA was obtained, which could be attributed to the use of a highly reflective ODR enabling better light extraction through the surface of the ODR-LED. Secondly, AlGaInP LEDs with textured surfaces provide a substantial improvement in light output power over the conventional structures. An AlGaInP ODR-LED with a two-dimensional “wavelike” surface was fabricated using the photolithography technique followed by an anisotropic etching process to texture the surface. Although there was a slight increase in the forward voltage and dynamic resistance (due to the current-crowding effect), the output power from LEDs with textured surface can be enhanced by 40% at 350 mA as compared with that of the LED sample without surface texturing. Moreover, the heavily carbon-doped GaP (³ 1 ´ 1019 cm-3) contact layer has been developed for the distributed-Bragg-reflector-enhanced absorbing-substrate AlGaInP LEDs using the indium tin oxide (ITO) as the current-spreading layer and transparent ohmic contact. The external quantum efficiency of the AlGaInP LED with the GaP:C/ITO structure can achieve 3.24% at 20 mA, representing a 78% efficiency improvement over the that of the LED sample without GaP:C/ITO structures.
URI: http://hdl.handle.net/11455/10289
其他識別: U0005-2208200619573200
Appears in Collections:材料科學與工程學系

Show full item record
 
TAIR Related Article

Google ScholarTM

Check


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