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Characterization of GaN Epitaxial Layers on Wet-etched Pattern Sapphire Substrates with Various Surface Treatments
|關鍵字:||GaN, patterned sapphire substrate|
|引用:|| T. Matsuoka, H. Okamoto, M. Nakao, H. Harima, E. Kurimoto, “Optical bandgap energy of wurtzite InN,” Appl. Phys. Lett., vol.81,pp. 1246-1248, 2002  B. G. Streetman, and S. Banerjee, “Solid state electronic devices,” 5th Ed., Prentice Hall, 2000  J. I. Pankove, “Gallium nitride (GaN) I,” Academic press, San Diego, 1998  H. P. Maraska, D. A. Stevenson, and J. I. Pankove, “Violet luminescence of Mg-doped GaN,” Appl. Phys. Lett., vol.22, pp. 303-305, 1973  S. Yoshida, S. Misawa, and S. Gonda, “Improvements on the electrical and luminescent properties of reactive molecular beam epitaxially grown GaN films by using AlN-coated sapphire substrates,” Appl. Phy. Lett., vol.42, pp. 427-429, 1983  H. Amanoet, T. Asahi, and I. Akasaki, “Stimulated emission near ultraviolet at room temperature from a GaN film grown on sapphire by MOVPE using an AlN buffer layer,” Jpn. J. Appl. Phys., vol.29, pp. 205-206, 1990  H. Amano, M. Kito, K. Hiramatsu, and I. Akasaki, “P-type conduction in Mg-doped GaN treated with low-energy electron beam irradiation (LEEBI),” Jpn. J. Appl. Phys., vol.28, pp. 2112-2114, 1989  S. Nakamura, “GaN growth using GaN buffer layer,” Jpn. J. Appl. Phys., vol.30, pp. 1705-1707, 1991  S. Nakamura, T. Mukai, M. Senoh, and N. Iwasa, “Thermal annealing effects on p-type Mg-doped GaN films,” Jpn. J. Appl. Phys., vol.31, pp. 139-142, 1992  T. Shibata, H. Sone, K. Yahashi, M. Yamaguchi, K. Hiramatsu, N. Sawaki, and N. Itoh, “Hydride vapor-phase epitaxy growth of high-quality GaN bulk single crystal by epitaxial lateral overgrowth,” J. Cryst. Growth, vol.189, pp. 67-71, 1998.  P. Fini, L. Zhao, B. Moran, H. Marchand, J. P. Ibbetson, M. Hansen, S. P. DenBaars, U. K. Mishra, and J. S. Speck , “High-quality coalescence of laterally overgrown GaN stripes on GaN/sapphire seed layers”, Appl. Phys. Lett., vol.75, pp. 1706-1708, 1999.  M. Yamada, T. Mitani, Y. Nakukawa, S. Shioji, I. Niki, S. Sonobe, K. Deguchi, M. Sano and T. Mukai, “InGaN-based near-ultraviolet and blue-light-emitting diodes with high external quantum efficiency using a patterned sapphire substrate and a mesh electrode,” Jpn. J. Appl. Phys., vol.41, pp. 1431-1433, 2002  K. Tadatomo, H. Okagawa, Y. Ohuchi, T. Tsunekawa, Y. Imada, M. Kato and T. Taguchi, “High output power InGaN ultraviolet light-emitting diodes fabricated on patterned substrates using metalorganic vapor phase epitaxy,” Phys. Stat. Sol. (a), vol.188, No. 1, pp. 121–125, 2001  http://www.phys.ksu.edu/area/GaNgroup/gparametm.html  O. Ambacher, “Growth and applications of Group III-nitrides” J. Phys. D: Appl. Phys., pp.2653-2710, 1998  L. Liu, J. H. Edgar, “Substrates for gallium nitride epitaxy,” Mater. Sci. & Eng., pp. 61–127, 2002  B. Beaumont, P. Gibart, “Epitaxial lateral overgrowth of GaN,” Phys. Stat. Sol. (b) 227, pp. 1–43, 2001  蕭宏，《半導體製程技術導論》，培升教育出版，民國92年  紀國鐘、蘇炎坤，《光電半導體技術手冊》，經濟部，民國91年  Y. J. Sung, H. S. Kim, Y. H. Lee, J. W. Lee, S. H. Chae, Y. J. Park, and G. Y. Yeom. “High rate etching of sapphire wafer using Cl2/BCl3/Ar inductively coupled plasmas,” Mater. Sci. & Eng., vol. 82, pp. 50-52, 2001  C. H. Jeong, D. W. Kim, K. N. Kim and G. Y. Ueom, “A study of sapphire etching characteristics using BCl3-based inductively coupled plasmas,” Jpn. J. App1. Phys., vol. 41, pp. 6206-6208, 2002  C. H. Jeong, D. W. Kim, J. W. Bae, Y. J. Sung, J. S. Kwak, Y. J. Park and G. Y. Yeom, “Dry etching of sapphire substrate for device separation in chlorine-based inductively coupled plasmas,” Mater. Sci. & Eng., vol.93, pp. 60-63, 2002  D. W. Kim, C. H. Jeong, K. N. Kim, H. Y. Lee, H. S. Kim, Y. J. Sung and G. Y. Yeom, “High rate sapphire (Al2O3) etching in inductively coupled plasmas using axial external magnetic field,” Thin Solid Film, vol. 435, pp. 242-246, 2003  C. H. Jeong, D. W. Kim, H. Y. Lee, H. S. Kim, Y. J. Sung and G. Y. Yeom, “Sapphire etching with BCl3/HBr/Ar plasma,” Surf. Coat. Technol., vol. 171, pp. 280-284, 2003  M. Berkenblit, J. Cuomo, and S. A. Chan, “Selected writings in crystallophysics and crystallography,” J. Electrochem. Soc., vol. 118, pp. 1653-1658, 1971  F. Dwikusuma, D. Saulys, and T.F. Kuech, “Study on sapphire surface preparation for III-Nitride heteroepitaxial growth by chemical treatments,” J. Electrochem. Soc., vol. 149, pp. 603-608, 2002  S. J. Kim, “Vertical electrode GaN-based light-emitting diode fabricated by selective wet etching technique,” Jpn. J. Appl. Phys., vol. 44, pp. 2921-2924, 2005  K. N. Tu, J. W. Mayer, and L. C. Feldman “Electronic thin film science: for electrical engineers and materials scientists,” Pearson Education POD, p. 355, 1996.  D. Hull, and D. J. Bacon, “Introduction to dislocations,” Pergamon Press, Oxford., p.234, 2001.  李玉柱, 《發光二極體之薄膜應力與光電特性的關係》, 成功大學機械工程學系研究所碩士論文, 2002.  X. H. Wu, C. R. Elsass, A. Abare, M. Mack, S. Keller, P. M. Petroff, S. P. DenBaars, and J. S. Speck, “Structural origin of V-defects and correlation with localized excitonic centers in InGaN/GaN multiple quantum wells,” Appl. Phys. Lett., vol. 72, pp. 692-694, 1998  S. Keller, G. Parish, J. S. Speck, S. P. DenBaars, and U. K. Mishra, “Dislocation reduction in GaN films through selective island growth of InGaN,” Appl. Phys. Lett., vol. 77, pp.2665-2667, 2000.  M. Kneissl, D. P. Bour, L. Romano, C. G. Van, J. E. Northrup, W. S. Wong, D. W. Treat, M. Teepe, T. Schmidt, and N. M. Johnson, “Performance and degradation of continuous-wave InGaN multiple-quantu-m-well laser diodes on epitaxially laterally overgrown Ga-N substrates,” Appl. Phys. Lett., vol. 77, pp.1931-1933, 2000  H. K. Cho, and J. Y. Lee, “Formation mechanism of V defects in the InGaN / GaN multiple quantum wells grown on GaN layers with low threading dislocation density,” Appl. Phys. Lett., vol. 79, pp.215-217, 2001  H. K. Cho, and J. Y. Lee, “Influence of strain-induced indium clustering on characteristics of InGaN / GaN multiple quantum wells with high indium composition,” J. Appl. Phys., vol. 91, pp.1104-1107, 2002.  李政鴻, 《AlInGaN UV LED 元件製作》 電光先鋒, pp.1-5, 2007  D. Morita, M. Yamamoto, K. Akaishi, K. Matoba, K. Yasutomo, Y. Kasai, M. Sano, S. I. Nagahama, and T. Mukai, “Watt-class high-output-power 365 nm ultraviolet light-emitting diodes,” Jpn. J. Appl. Phys., vol. 43, pp. 5945-5950, 2004  T. Hino, S. Tomiya, T. Miyajima, K. Yanashima, S. Hashimoto, and M. Ikeda, “Characterization of threading dislocations in GaN epitaxial layers,” Appl. Phys. Lett., vol.76, pp. 3421-3423, 2000  J. E. Ayers, “The measurement of threading dislocation densities in semiconductor crystals by X-ray diffraction,” J. Crystal Growth, vol. 135, pp.71-77, 1994  T. Metzger, R. Hopler, E. Born, O. Ambacher, M. Stutzmann, R. Stommer, M. Schuster, H. Gobel, S. Christiansen, M. Albrecht, and H. P . Strunk, “Defect structure of epitaxial GaN films determined by transmission electron microscopy and triple-axis X-ray diffractometry,” Philos. Mag. A., vol.77, pp. 1013-1025, 1998  B. Heying, X. H. Wu, S. Keller, Y. Li, D. Kapolnek, B. P. Keller, S. P. DenBaars, and J. S. Speck, “Role of threading dislocation structure on the x-ray diffraction peak widths in epitaxial GaN films,” Appl. Phys. Lett., vol. 68, pp. 643-645, 1996  R. Chierchia, T. B. Wttcher, H. Heinke, S. Einfeldt, S. Figge, and D. Hommel, “Microstructure of heteroepitaxial GaN revealed by x-ray diffraction,” J. Appl. Phys., Vol. 93, pp. 8918-8925, 2003  D. J. Kang, I. S. Kim, J. H. Moon, B. T. Lee, “Inductively coupled plasma reactive ion etching of sapphire using C2F6- and NF3- based gas mixtures,” Mater. Sci. in Semi. Processing, vol. 11, pp. 16-19, 2008  J. H. Lee, J. T. Oh, J. S. Park, “Improvement of luminous intensity of InGaN light emitting diodes grown on hemispherical patterned sapphire”, phys. stat. sol. (c) 3, No. 6, pp. 2169–2173, 2006  J. C. Zhang, D. S. Jiang, Q. Sun, J. F. Wang, Y. T. Wang, J. P. Liu, J. Chen, R. Q. Jin, J. J. Zhu, H. Yang, T. Dai, and J. Jia, “Influence of dislocations on photoluminescence of InGaN / GaN multiple quantum wells,” Appl. Phys. Lett., vol. 87, pp. 071908-071911, 2005.  S. K. Mathis, A. E. Romanov, L. F. Chen, G. E. Beltz, W. Pompe, and J. S. Speck, “Modeling of threading dislocation reduction in growing GaN layers,” J. Cryst. Growth, vol. 231, pp. 371-390, 2001|
|摘要:||本論文將以乾式蝕刻對圖案化的藍寶石基板作表面處理，並探討以此基板所成長之氮化鎵薄膜的品質特性。本實驗採用的蝕刻氣體為四氟化碳，對藍寶石基板的蝕刻速率為180 A/min。當藍寶石基板用於成長氮化鎵薄膜時，由於兩種材料的晶格常數不匹配(晶格常數相差16 %)，所成長的氮化鎵薄膜將產生許多缺陷，影響薄膜品質。這樣的結果使得載子輻射複合效率降低與產生大漏電流情況，為改善薄膜品質，論文中利用濕式蝕刻完成圖案化藍寶石基板的製作，再使用感應式耦合電漿蝕刻機台做表面處理，藉由乾式蝕刻對基板表面的粗糙度改變，以降低成長後的氮化鎵薄膜缺陷密度。
文章中分析比較乾式蝕刻做表面處理的前後氮化鎵薄膜性質。以高解析雙晶繞射儀、蝕刻孔洞密度法、光激發光光譜圖、掃描式電子顯微鏡與穿透式電子顯微鏡分析結果顯示，經過表面處理的圖案化藍寶石基板，其氮化鎵磊晶膜在高解析雙晶繞射對稱面(0002)面搖擺曲線半高寬降低17 %，非對稱面(10-12)面搖擺曲線半高寬降低12 %，載子遷移率由146 cm2/v-s增加至219 cm2/v-s，顯示薄膜品質有因此改善。|
In this thesis, the characteristics of GaN epilayers grown on the wet-etched pattern sapphire substrates (PSSs) with various dry etching treatments have been investigated. The CF4 was used as the etching gas, achieving an etching rate of 180 A/min for the sapphire substrate. The PSS was treated using an inductively-couple-plasma etching system to modify the PSS surface morphology. It is well known that there exist high density defects in the GaN epilayer due to the large lattice mismatch between GaN and sapphire (~16 %). It will reduce the radiative recombination efficiency and cause large leakage current. Moreover, the treatment effects on the crystallinity and optical properties of GaN epilayers will be discussed. We analyzed the results of GaN epilayer grown on wet-etched PSS with and without surface treatment. The GaN epilayer was measured by double-crystal x-ray diffractometry, etch pit density, photoluminescence, scanning electron microscopy, transmission electron microscopy, and van-der Hall measurement. The full widths at half maximum of both x-ray rocking curves in (0002) and (10-12) faces of the GaN epilayer on treated PSS were decreased by 17% and 12%, respectively as compared with those of the sample on untreated PSS. In addition, the electron mobility was increased by 50 % (from 146 cm2/v-s to 219 cm2/v-s). These results indicate that the improvement in epitaxial quality of GaN can be achieved on the PSS with a suitable post dry-etching treatment.
|Appears in Collections:||精密工程研究所|
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