本研究利用創新設計之低溫氣相冷凝系統製備n型鉿摻雜氧化鎵薄膜與鋁摻雜之氧化鋁鎵薄膜，再以磁控濺鍍射頻系統將p型氧化鎳薄膜堆疊於氧化鋁鎵薄膜上，將氧化鋁鎵與氧化鎵交互堆疊製作出多重量子井，成功製備出n型鉿摻雜氧化鎵/多重量子井/p型氧化鎳之深紫外光發光二極體元件。
其分析內容分為n型鉿摻雜氧化鎵薄膜與p型氧化鎳薄膜，並探討薄膜特性。在p型氧化鎳薄膜方面，以磁控式濺鍍系統進行製作，以鎳為靶材並藉由通入不同流量的氮氣與氧氣，製作出鎳氧比不同的氧化鎳薄膜，最後利用霍爾量測進行薄膜分析，可知當氧氣流量增加時薄膜中之載子濃度由4.7×1016 cm-3提升至7.5×1016cm-3；而多重量子井方面，則是使用本質氧化鎵與鋁摻雜氧化家互相堆疊，形成量子井結構，當此結構不只一層時，則會形成多重量子井；另一方面，為了有效製作出n型氧化鎵薄膜，將採用氧化鎵粉末與二氧化鉿粉末進行共蒸鍍，利用高溫熱處理使得鉿元素摻入氧化鎵薄膜中，藉由改變蒸鍍源靶材重量，製作出不同鉿摻雜含量的n型氧化鎵薄膜，最後利用霍爾量測進行薄膜分析，可知薄膜中之鉿摻雜量增加使濃度由1.1×1015 cm-3提升至1.1×1017 cm-3，並對光學能隙進行探討，由於二氧化鉿光學能隙(Eg =5.6 eV)大於氧化鎵之光學能隙(Eg = 4.9 eV)，故不同重量之鉿摻雜n型氧化鎵薄膜之光學能隙將隨著鉿摻雜量的增加而有所提升；此外，亦對於薄膜的結晶特性進行分析，由於鉿離子(Hf4+)的離子半徑為0.71 Å，而鎵(Ga3+)離子的離子半徑為0.62 Å，因此薄膜中的鉿離子(Hf4+)取代鎵(Ga3+)離子時，導致單位晶胞體積與晶格常數增加，而使得薄膜中特徵鋒值由30.66o減少至30.57o。
本研究將n型鉿摻雜之氧化鎵薄膜、多重量子井及p型氧化鎳薄膜組合後成功製成深紫外光發光二極體，我們定義驅動發光二極體的最小電流0.5m為啟動電流，而其對應電壓則為啟動電壓，當多重量子井對數為4、5、6、7對時，其啟動電壓為 11.67V、11.85V、12.13V、12.36V，且其發光波段位於243 nm。

In this study, an n-type gallium oxide film was fabricated using an innovative vapor cooling condensation system and an p-type nickel oxide film were fabricated by RF magnetron sputtering system to prepare a deep ultraviolet light-emitting diode.
The p-type nickel oxide film deposited in different gas flow, and did the Hall and EDS measurement. As oxygen gas flow increase, carrier concentration increases from 4.7 x 1016 cm-3 to 7.5 x 1016 cm-3. On the other hand, the gallium oxide powder and the hafnium dioxide powder are co-evaporated, and then an n-type gallium oxide thin film is formed by high temperature heat treatment. As the number of grams of hafnium dioxide increases, the optical energy gap increases and the carrier concentration increases from 1.1 x 1015 cm-3 to 1.1 x 1017 cm-3. In addition, since the ionic radius of the hafnium ion (Hf4+) is 0.71 Å, and the ionic radius of the gallium ion (Ga3+) is 0.62 Å, the lattice constant increases when the hafnium ion replaced the gallium ion. This decreases the XRD diffraction angle from 30.66o to 30.57o.
Using the structure of n-Ga2O3/MQW/p-NiOx, we successfully fabricated a deep ultraviolet light-emitting diode. We determine the minimum current to drive led 0.5 mA as starting current, and the correspond bias as starting bias of 11.67 V、11.85 V、12.13 V、12.36 V for 4/5/6/7 pairs of multi-quantum well and the emission band was about 243 nm.

[1] http://www.intertek-twn.com/frontend/newseventsview.aspx?lang=C&no=1346
[2] 葉純宜、林明瀅、陳小妮、王復德，紫外線殺菌效能探討，感染控制雜誌，15卷，頁數293-300，2005年。
[3] T. Y. Tsai, S. L. Ou, M. T. Hung, D. S. Wuu, and R. H. Horng, “MOCVD groeth of GaN on sapphire using a Ga2O3 interlayer,” J. Elctrochem. Soc., Vol. 158, pp. H1172-H1178, 2011.
[4] W. Wenliang, W. Haiyan, Y. Weijia, Z. Yunnong, and L. Guoqiang. “A new approach to epitaxially grow high-quality GaN films on Si substrates: the combination of MBE and PLD,” Sci. Rep., vol. 6, p. 24448, 2016.
[5] S. J. Pearton, J. Yang, P. H. Cary, F. Ren, J. Kim, M. J. Tadjer, and M. A. Mastro,” A review of Ga2O3 materials, processing, and devices,” Appl. Phys. Rev., vol. 5, p. 011301, 2018.
[6] H. Y. Lee, J. T. Liu, and C. T. Lee, “Modulated Al2O3-alloyed Ga2O3 materials and deep ultraviolet photodetectors,” IEEE Photonics Technol. Lett., vol. 30, pp. 549-552, 2018.
[7] L. X. Qian, H. F. Zhang, Z. H. Wu, and X. Z. Liu, “High-sensitivity β-Ga2O3 solar-blind photodetector on high-temperature pretreated c-plane sapphire substrate,” Opt. Mater. Express, vol. 7, pp. 3643-3653, 2017.
[8] Jian, LY., Lee, HY. & Lee, CT. “Ga2O3-based p-i-n solar blind deep ultraviolet photodetectors,” J Mater Sci: Mater Electron vol 30, pp. 8445–8448, 2019.
[9] Chu S-Y, Shen M-X, Yeh T-H, Chen C-H, Lee C-T, Lee H-Y. “Investigation of Ga2O3-Based Deep Ultraviolet Photodetectors Using Plasma-Enhanced Atomic Layer Deposition System,” Sensors., vol. 5, 2020.
[10] C.-H. Lin and C.-T. Lee, “Ga₂O₃-based solar-blind deep ultraviolet light-emitting diodes,” J. Lumin., vol. 224, Article 117326, 2020.
[11] M. Higashiwaki, K. Sasaki, T. Kamimura, M. H. Wong, D. Krishnamurthy, A. Kuramata, T. Masui, and S. Yamakoshi, “Depletion-mode Ga2O3 metal-oxide-semiconductor field-effect transistors on β-Ga2O3 (010) substrates and temperature dependence of their device characteristics,” Appl. Phys. Lett., vol. 103, p. 123511, 2013.
[12] W. Mu, Z. Jia, Y. Yin, Q. Hu, Y. Li, B. Wu, J. Zhang, and X. Tao, “High quality crystal growth and anisotropic physical characterization of β-Ga2O3 single crystals grown by EFG method,” J. Alloys Compd., vol. 714, pp. 453–458, 2017.
[13] N. Ueda, H. Hosono, R. Waseda, and H. Kawazoe, “Synthesis and control of conductivity of ultraviolet transmitting β-Ga2O3 single crystals,” Appl. Phys. Lett., vol. 70, pp. 3561–3562, 1997.
[14] M. Fleischer, L. Hollbauer, and H. Meixner, “Effect of the sensor structure on the stability of Ga2O3 sensors for reducing gases,” Sens. Actuators B, vol. 18, pp. 119–124, 1994.
[15] Z. Li, Z. An, Y. Xu, Y. Cheng, Y. Cheng, D. Chen, Q. Feng, S. Xu, J. Zhang, C. Zhang, and Y. Hao, “Improving the production of high-performance solar-blind beta-Ga2O3 photodetectors by controlling the growth pressure,” J. Master, Sci., vol. 54, pp. 10335-10345, 2019.
[16] A. Pratiyush, U. UI Muazzam, S. Kumar, P. Vijayakumar, S. Ganesamoorthy, N. Subramanian, R. Muralidharan, and D. Nath, “Optical float-zone grown bulk beta-Ga2O3-based lineat MSM array of UV-C photodetectors,” IEEE Photonics Technol. Lett., vol. 31, pp. 923-926, 2019.
[17] L. Y. Jian, H. Y. Lee, and C. T. Lee, “Ga2O3-based p-i-n solar blind deep ultraviolet photodetectors,” J. Mater. Sci-Mater. Electron., vol. 30, pp. 8445-8448, 2019.
[18] W. Man Hoi, G. Ken, M. Hisashi, K. Yoshinao, and H. Masataka, “Current aperture vertical β-Ga2O3 MOSFETs fabricated by N- and Si-ion implantation doping,” IEEE Electron Device Lett., vol. 40, pp. 431-434, 2019.
[19] J. Mun, K. Cho, W. Chang, H. W. Jung, and J. Do, “2.32KV breakdown voltage lateral beta-Ga2O3 MOSFETs with source-connected field plate,” ECS J. Solid State Sci. Technol., vol. 8, pp. Q3079-Q3082, 2019.
[20] Y. J. Lv, X. B. Song, Z. Z. He, X. Tan, Z. Y. Zhou, Y. G. Wang, G. D. Gu, and Z. H. Feng, “Ga2O3 MOSFET Device with Al2O3 gate dielectric,” J. Inorg. Master., vol. 33. pp. 976-980, 2018.
[21] L. Kong, J. Ma, and C. Luan, “Structural and optical properties of heteroepitaxial beta Ga2O3 films grown on MgO (100) substrates”, Thin Solid Films, vol. 520, pp. 4270-4274, 2012
[22] S. S. Kumar, E. J. Rubio, M. Noor-A-Alam, G. Martinez, S. Manandhar, V. Shutthanandan, S. Thevuthasan, and C. V. Ramana, “Structure, morphology, and optical properties of amorphous and nanocrystalline gallium oxide thin films”, J. Phys. Chem. C, vol.117, pp. 4194-4200, 2013.
[23] N. Winkler, R. A. Wibowo, W. Kautek, G. Ligorio, E. J. W. List-kratochvil, and T. Dimopoulos, “Nanocrystalline Ga2O3 films deposited by spray pyrolysis from water-based solutions on glass and TCO substrates,” J. Mater. Chem. C, vol. 7, pp. 69-77, 2019.
[24] Trinchi A, Wlodarski W, and Y. X. Li, “Hydrogen sensitive Ga2O3 Schottky diode sensor based on SiC,” Sens. Actuator B-Chem., vol. 100, pp. 94–98, 2004.
[25] Z. X. Feng, M. R. Karim, and H. P. Zhao, “Low Pressure chemical vapor deposition of beta-Ga2O3 thin film: dependence on growth parameters,” APL Mater., vol. 7, p. 022514, 2019.
[26] M. Q. Li, N. Yang, G. G. Wang, H. Y. Zhang, and J. C. Han, “Highly preferred orientation of Ga2O3 films sputtered on SiC substrates for deep UV photodetector application,” Appl. Surf. Sci., vol. 471, pp. 694-702, 2019.
[27] M. Rebien, W. Henrion, M. Hong, J. P. Mannaerts, and M. Fleischer, “Optical properties of gallium oxide thin films,” Appl. Phys. Lett., vol. 81, pp. 250-252, 2002.
[28] F. Alema, B. Hertog, A. Osinsky, P. Mukhopadhyay, M. Toporkov, and W. V. Schoenfeld, “Fast growth rate of epitaxial β–Ga2O3 by close coupled showerhead MOCVD,” J. Cryst. Growth, vol. 475, pp. 77-82, 2017.
[29] Y. C. Cai, K. Zhang, Q. Feng, Y. Zuo, Z. Z. Hu, Z. Q. Feng, H. Zhou, X. L. Lu, C. F. Zhuang, W. H. Tang, and J. C. Zhang, “Tin-assisted growth of epsilon-Ga2O3 film and the fabrication of photodetectors on sapphire substrate by PLD,” Opt. Mater. Express, vol. 8, pp. 3506-3517, 2018.
[30] J. T. Yan and C. T. Lee, “Improved detection sensitivity of Pt/β-Ga2O3/GaN hydrogen sensor diode,” Sens. Actuators B, vol. 143, pp. 192-197, 2009.
[31] N. Ohshima, M. Nakada, and Y. Tsukamoto, “Structural and Magnetic Properties of Ni-O/Ni-Fe Bilayer Films”, Jpn. J. Appl. Phys., vol. 35, pp. L1585-L1588, (1996).
[32] O. Kohmoto, H. Nakagawa, F. Ono, and A. Chayahara, “Ni-Defective Value and Resistivity of Sputtered NiO films”, J. Magn. Magn. Mater., vol. 226-230, pp. 1627-1629, (2001).
[33] 黃國倫, “銅添加對氧化鎳薄膜透光性及導電性之影響”, 國立成功大學材料科學及工程學系碩士論文, (2006)
[34] E. Fujii, A. Tomozawa, H. Torii, and R. Takayama, “Preferred Orientations of NiO Films Prepared by Plasma-Enhanced Metalorganic Chemical Vapor Deposition”, Jpn. J. Appl. Phys., vol. 35, pp. L328-L330, (1996).
[35] M. Kitao, K. Izawa, K. Urabe, T. Komatsu, S. Kuwano, and S. Yamda, “Preparation and Electrochromic Properties of RF-Sputtered NiOx Films Prepared in Ar/O2/H2 Atmosphere” , Jpn. J. Appl. Phys., vol. 33, pp. 6656-6662, (1994).
[36] H. Kumagai, M. Matsumoto, K. Toyoda, and M. Oobara, “Preparation and Characteristics of Nickel Oxide Thin Film by Controlled Growth with Sequential Surface Chemical Reactions”, J. Mater. Sci. Lett., vol. 15, pp. 1081-1803, (1996)
[37] A. Zukauskas, “Introduction to solid-state lightion,” John Wiley & Sons, New York, 2002.
[38] Sir Norman Lockyer, “Nature,” Macmillan Journals Limited, 1879.
[39] R. S. Bauer, “Surfaces and Interfaces: Physics and Electronics,” Elsevier, 2012.
[40] S. M. Sze, “Semiconductor device physics and technology 2nd edition,” Wiley, chap. 7.1, 2001.
[41] K. K. Bharathi, N. R. Kalidindi, and C. V. Ramana, “Grain size and strain effects on optical and electrical properties of hafnium oxide nanocrystalline thin film,” J. Appl. Phys., vol.108, pp. 083529-1-083529-5, 2010.
[42] S. S. Kumar, E. J. Rubio, M. Noor-A-Alam, G. Martinez, S. Manandhar, V. Shutthanandan, S. Thevuthasan, and C. V. Ramana, “Structure, morphology, and optical properties of amorphous and nanocrystalline gallium oxide thin films,” J. Phys. Chem. C, vol. 117, pp. 4194-4200, 2013.
[43] H. Morkoc, A. D. Catlo, and R. Cingolani, “GaN-based modulation doped FETs and UV detector,” Solid-State Electron., vol. 46, p. 157, 1999.
[44] B. P. Luther, S. D. Wolter, and S. E. Mohney, “High temperature Pt Schottky diode gas sensors on n-type GaN,” Sens. Actuator B-Chem., vol. 56, p. 164, 1999.
[45] Nakamura, T. Mukai, and M. Senoh, “Candela-class high-brightness InGaN/AlGaN double-heterostructure blue-light-emitting diodes,” Appl. Phys. Lett., vol. 64, p. 1687, 1994.
[46] H. Y. Lee, S. D. Xia, W. P. Zhang, L. R. Lou, J. T. Yan, and C. T. Lee, “Mechanisms of high quality i-ZnO thin films deposition at low temperature by vapor cooling condensation technique,” J. Appl. Phys., vol. 108, pp. 073119-1-073119-6, 2010.
[47] V. R. Aline, O. Marcelo, and Orlandi, “Study of intense photoluminescence from mondispersed β-Ga2O3 ellipsoidal structures,” Ceram. Int., vol. 45, pp. 5023-5029, 2019.
[48] B. Pivac, K. Furic, and D. Desnica, “Raman line profile in polycrystalline hafnium,” J. Appl. Phys., vol. 86, p. 4383, 1999.
[49] S. Y. Yoon, S. J. Park, K. H. Kim, and J. Jang, “Structural and electrical properties of polycrystalline hafnium produced by low-temperature Ni silicide mediated crystallization of the amorphous phase,” J. Appl. Phys., vol. 87, p. 609, 2000.
[50] A. A. Al-Tabbakh, N. Karatepe, A. B. Al-Zubaidi, A. Benchaabane, and N. B. Mahmood, “Crystallite size and lattice strain of lithiated spinel material for rechargeable battery by X-ray diffraction peak-broadening analysis,” Int. Energy Res., vol. 43, pp. 1903-1911, 2019.
[51] J. Pankove, “Absorption edge of impure gallium arsenide,” Physical Review, vol. 140 p. 2059, 1965.
[52] H. Y. Lee, S. D. Xia, W. P. Zhang, L. R. Lou, J. T. Yan, and C. T. Lee, “Mechanisms of high quality i-ZnO thin films deposition at low temperature by vapor cooling condensation technique,” J. Appl. Phys., vol. 108, pp. 073119-1-073119-6, 2010.
[53] S. Yan, L. Wan, Z. Li, Y. Zhou, and Z. Zou “Synthesis of a mesoporous single crytal Ga2O3 nanoplate with improved photoluminescence and high sensitivity in detecting CO,” Chem. Commun., vol. 46, pp. 6388-6390, 2010.
[54] D. Gogova, G. Wangner, M. Baldini, M. Schmidbauer, K. Irmscher, R. Schewski, Z. Galazka, M. Albrecht, and R. Fornari, “Structural properties of Si-doped β-Ga2O3 layers grown by MOVPE,” Ceram. Int., vol. 44, pp. 3122-3127, 2018.
[55] T. Kenichiro, F. Suguru, T. Isao, O. Hidenori, T. Daisuke, N. Toshiyuki, S. Mutsuo, M. Katsuya, S. Eddy, and C. Cor, “Investigation of Si doping effect in β-Ga2O3 films by co-sputtering of gallium oxide and Si.” Physica B, vol. 407, pp. 2900-2902, 2012.
[56] D. Hu, Y. Wang, S. Zhuang, X. Dong, Y. Zhang, J. Yin, B. Zhang, Y. Lv, Z. Feng, G. Du, “Surface morphology evolution and optoelectronic properties of heteroepitaxial Si-doped beta-Ga2O3 thin films grown by metal-organic chemical vapor deposition,” Ceram. Int., vol. 44, pp. 3122-3127, 2018.
[57] C. H. Lin, and C. T. Lee, “Ga2O3-based solar-blind deep ultraviolet light-emitting diodes” J. Lumin., 224 (2020), Article 117326.
[58] V. Malyutenko, S. S. Bolgov, and A. D. Podoltsev, “Current crowding effect on the ideality factor and efficiency droop in blue lateral InGaN/Gan light emitting diodes,” Appl. Phys. Lett., vol. 97, p. 251110, 2010.
[59] D. Wang, S. Feng, C. Lu, A. Motayed, M. Jah, S. Mohammad, K. Jones, and L. Salamanca-Riba, “Low-resistance Ti/Al/Ti/Au multilayer ohmic contact to n-GaN,” J. Appl. Phys., vol. 89, pp. 6214-6217, 2001.