| 研究生: |
鍾政霖 Jeng-Lin Chung |
|---|---|
| 論文名稱: |
氧化鋅摻鈦透明導電薄膜之性質研究 Structural, electrical and optical properties of TiO2 -doped ZnO films prepared by radio frequency magnetron sputtering |
| 指導教授: |
曾重仁
Chung-Jen Tseng |
| 口試委員: | |
| 學位類別: |
博士 Doctor |
| 系所名稱: |
工學院 - 機械工程學系 Department of Mechanical Engineering |
| 畢業學年度: | 96 |
| 語文別: | 中文 |
| 論文頁數: | 124 |
| 中文關鍵詞: | 氧化鋅 、電阻率 、能隙 |
| 外文關鍵詞: | ZnO, resistivity, energy band gap |
| 相關次數: | 點閱:11 下載:0 |
| 分享至: |
| 查詢本校圖書館目錄 查詢臺灣博碩士論文知識加值系統 勘誤回報 |
由於透明導電膜廣泛應用於光電元件中,尤其氧化鋅薄膜可以同時具有光與電性質,所以許多學者認為可以取代ITO薄膜。在本實驗以鈦摻入氧化鋅(TiO2 -doped ZnO)薄膜來研究其結構、電及光學性質。沉積TiO2 -doped ZnO薄膜在氬氣氣氛下,在較低之沉積壓力與較高之基板溫度,其結晶性排列較緊密,有較低之電阻率值為2.50 × 10-3 Ω-cm,而鈦摻雜量為1.34 wt %。TiO2 -doped ZnO薄膜在可見光區其光穿透率皆可達到80%以上,而其光能隙與載子濃度有關,其範圍為3.30~3.48 eV。為了提升元件效率,更進一步降低電阻率是必行之路,由於氫元素可以改善氧化鋅導電特性,因此藉由Ar+H2氣氛來沉積TiO2 -doped ZnO薄膜,氫氣比例為15%時,有最低之電阻率為6.50 × 10-4 Ω-cm,而鈦摻雜量為1.28 wt % ;不同氫含量比例對於TiO2 -doped ZnO薄膜之穿透率皆可達到85%以上,其能隙被寬化由3.42 eV增加至3.72 eV,隨著載子濃度增加而增加。在氫氬混合氣氛下摻鎂對於TiO2 -doped ZnO薄膜之性質分析,在340 ~ 350 之間有(002)繞射峰,隨著MgO摻雜含量增加,其(002)繞射峰強度漸漸減少;由實驗分析其電阻率隨著鎂含量增加而增加;在可見光區,光穿透率皆可達到85%以上;可以觀察到隨著鎂含量增加,其光學吸收限向著短波長方向偏移。
Transparent conducting oxide films have lately attracted a great deal of attention because of their properties of low electrical resistivity and high transmittance in the visible region. Impurity-doped ZnO films, with their good electrical and optical properties, are a promising alternative to replace ITO films for transparent electrode applications.
TiO2-doped zinc oxide thin films were deposited on glass substrates by radio frequency (RF) magnetron sputtering with TiO2-doped ZnO targets in an argon atmosphere. The crystalline structure of the TiO2-doped ZnO films gradually improved as the working pressure was lowered and the substrate temperature was raised. The lowest electrical resistivity for the TiO2-doped ZnO films was obtained when the Ti addition was 1.34 wt%; its value was 2.50 × 10-3 Ω-cm. The transmittance of the TiO2-doped ZnO films in the visible wavelength range was more than 80 %. The optical energy gap was related to the carrier concentration, and was in the range of 3.30-3.48 eV.
Highly conductive, transparent TiO2-doped ZnO films are grown by radio frequency (RF) magnetron sputtering in ambient hydrogen-argon (Ar+H2) gas at a temperature of 150 0C. Van de Walle has shown theoretically that hydrogen can act as a shallow donor to become a source of electrical conductivity. The lowest resistivity obtained is 6.50 × 10-4 Ω-cm with 1.28 wt% Ti and 15% H2 content in Ar. The optical transmittance for TiO2-doped ZnO films in the visible region is about 85 %. Due to the Burstein-Moss effect, the energy band gap increases with the carrier concentration.
Polycrystalline TiO2-doped ZnO films doped with MgO in ambient hydrogen-argon (Ar+H2) gas are prepared on glass substrates by RF magnetron sputtering. Increasing the Mg content from 0 to 17.75 wt% increases the electrical resistivity from 6.50×10-4 Ω-cm to the high resistivity. TiO2-doped ZnO films doped with MgO are an excellent wide band gap material, and its band gap varies with Mg content.
1. 李玉華, ”透明導電膜及其應用”, 科儀新知, 12卷第一期, (79), 94-102.
2. 許國銓, ”科技玻璃-高性能透明導電玻璃”, 材料與社會, 84期, (82), 110-119.
3. J. Ma, J. Feng, “Electrical and optical properties of ZnO: Al films prepared by an evaporation method”, Thin Solid Films, 279 (1996) 213.
4. T. Minami, H. Sato, H. Nanto, S. Takata, “Group Ⅲ Impurity Doped Zinc Oxide Thin Films Prepared by RF magnetron sputtering”, Jpn. J. Appl. Phy., 24 (1985) L781.
5. H.L. Hartnagel, A.L. Dawar, A.K. Jain, C. Jagadish, “Semiconducting Transparent Thin Films”, Institute of Physics Publishing, Bristol, 1995.
6. K. M. Lakin, J. S. Wang, “Acoustic bulk wave composite resonators”, Appl. Phys. Lett. 38 (1981) 125.
7. C. Agashe, O. Kluth, G. Schöpe, H. Siekmann, J. Hüpkes, B. Rech, “Optimization of the electrical properties of magnetron sputtered aluminum-doped zinc oxide films for opto-electronic applications”, Thin Solid Films 442 (2003) 167.
8. X. Yu, J. Ma, F. Ji, Y. Wang, X. Zhang, C. Cheng, H. Ma, “ Preparation and properties of ZnO:Ga films prepared by r.f. magnetron sputtering at low temperature“Appl. Surf. Sci. 239 (2005) 222.
9. D. Y. Ku, I. H. Kim, I. Lee, K. S. Lee, T. S. Lee, J.-h. Jeong, B. Cheong, Y.-J. Baik, W. M. Kim, “Structural and electrical properties of sputtered indium–zinc oxide thin films”, Thin Solid Films 515 (2006) 1364.
10. T. S. Moss, “The Interpretation of the Properties of Indium Antimonide”, Phys. Soc. London Sect. B, 67 (1954) 775.
11. E. Burstein, “Anomalous Optical Absorption Limit in InSb”, Phys. Rev., 93 (1954) 632.
12. S.A. Studenikin, N. Golego, M. Cocivera, ”Carrier mobility and density contributions to photoconductivity transients in polycrystalline ZnO films”, J. Appl. Phys. 87 (2000) 2413.
13. J. Hu, R.G. Gordan, “Textured aluminum-doped zinc oxide thin films from atmospheric pressure chemical-vapor deposition”, J. Appl. Phys. 71 (1992) 880.
14. H. U. Habermeier, “Properties of Indium Tin Oxide Thin Films Prepared by Reactive Evaporation”, Thin Solid Films, 80 (1981) 157.
15. F. Furusaki, J. Takahashi, K. Kodaira, “Preparation of ITO Thin films by Sol-Gel Method”, J. of the Ceramic Society of Japan, 102 (1994) 200.
16. Z.-C. Jin, I. Hamberg, C.G. Granqvist, “Optical properties of sputter-deposited ZnO:Al thin films”, J. Appl. Phys. 64 (1988) 5117.
17. 莊達人,“VLSI製造技術”,高立圖書有限公司, 2002年7月20日五版修訂
18. D. S. Richerby and A. Matthews, “Advanced Surface Coatings: A Handbook of Surface Engineering”, Chapaman and Hall, New York, (1991) 92.
19. S. M. Rossnagel et al., “Handbook of Plasma Processing Technology”, Noyes Publications, Park Ridge, New Jersey, U.S.A., (1982).
20. 楊錦章,“基礎濺鍍電漿”, 電子發展月刊, 68期, (72), 13-40.
21. Brian Chapman, “Glow Discharge Processes”, John Wiley and Sons, New York, (1980).
22. N. Fujimura, T. Nishihara, S. Goto, J. Xu, T. Ito, “Control of preferred orientation for ZnOx films: control of self-texture”, J. Cryst. Growth 130 (1993) 269.
23. T. Minanmi, “Transparent conducting oxide semiconductors for transparent electrodes”, Semicond. Sci. Technol. 20 (2005) S35.
24. Y. M. Lu, C. M. Chang, S. I. Tsai, T. S. Wey, “Improving the conductance of ZnO thin films by doping with Ti”, Thin Solid Films 447-448 (2004) 56.
25. S. S. Lin, J. L. Huang, D. F. Lii, “ Effect of substrate temperature on the properties of Ti-doped ZnO films by simultaneous rf and dc magnetron sputtering“, Mater. Chem. Phys. 90 (2005) 22.
26. A. Van der Drift, “Evolutionary selection, A Principle Governing Growth Orientation In Vapour-Deposited Layers“, Philips Res. Rep. 22 (1967) 267.
27. K. H. Yoon, J. W. Choi and D. H. Lee, “Characteristics of ZnO thin films deposited onto Al/Si substrates by r.f. magnetron sputtering”, Thin Solid Films 302 (1997) 116.
28. S. Takada, “Relation between optical property and crystallinity of ZnO thin films prepared by rf magnetron sputtering”, J. Appl. Phys. 73 (1993) 4739.
29. B. Y. Oh, M. C. Jeong, W. Lee, J. M. Myoung, “Properties of transparent conductive ZnO:Al films prepared by co-sputtering”, J. Cryst. Growth 274 (2005) 453.
30. X. Yu, J. Ma, F. Ji, Y. Wang, C. Cheng, H. Ma, “Thickness dependence of properties of ZnO:Ga films deposited by rf magnetron sputtering”, Applied Surface Science 245 (2005) 310.
31. Y. Ohya, H. Saiki, T. Tanaka, Y. Takahashi,” Microstructure of TiO2 and ZnO films fabricated by the sol-gel method”, J. Am. Ceram. Soc. 79 (1996) 825.
32. J. W. Christian, “The Theory of Transformation in Metals and Alloys”, 2nd ed., Part 1, Pergamon Press, Oxford, U. K., (1975).
33. S. H. Jeong, J. W. Lee, S. B. Lee, J. H. Boo, “Deposition of aluminum-doped zinc oxide films by RF magnetron sputtering and study of their structural, electrical and optical properties”, Thin Solid Films 435 (2003) 78.
34. S. H. Jeong, J. H. Boo, “Influence of target-to-substrate distance on the properties of AZO films grown by RF magnetron sputtering”, Thin Solid Films 447 (2004) 105.
35. V. Assunção, E. Fortunato, A. Marques, H. Águas, I. Ferreira, M. E. V. Costa, R. Martins, “Influence of the deposition pressure on the properties of transparent and conductive ZnO:Ga thin-film produced by r.f. sputtering at room temperature”, Thin Solid Films 427 (2003) 401.
36. W. Tang, D. C. Cameron, “Aluminum-doped zinc oxide transparent conductors deposited by the sol-gel process”, Thin Solid Films 238 (1994) 83.
37. W.W. Wang, X.G. Diao, Z. Wang, M. Yang, T.M. Wang, Z. Wu, “Preparation and characterization of high-performance direct current magnetron sputtered ZnO:Al films”, Thin Solid Films 491 (2005) 54.
38. J. Yoo, J. Lee, S. Kim, K. Yoon, I. J. Park, S.K. Dhungel, B. Karunagaran, D. Mangalaraj, J.Yi, “High transmittance and low resistive ZnO:Al films for thin film solar cells”, Thin Solid Films 480-481 (2005) 213.
39. T. Minami, H. Nanto, S. Takata, ”Highly Conductive and Transparent Aluminum Doped Zinc Oxide Thin Films Prepared by RF Magnetron Sputtering”, Jpn. J. Appl. Phys. 23 (1984) L280.
40. Su-Shia Lin, Jow-Lay Huang, Ding-Fwu Lii, “The effect of thickness on the properties of Ti-doped ZnO films by simultaneous r.f. and d.c. magnetron sputtering”, Surface and Coatings Technology 190 (2005) 372.
41. Su-Shia Lin, Jow-Lay Huang, P. ajgalik, “The properties of Ti-doped ZnO films deposited by simultaneous RF and DC magnetron sputtering”, Surface and Coatings Technology 191 (2005) 286.
42. Y. -J. Kim, H. -J. Kim, “Trapped oxygen in the grain boundaries of ZnO polycrystalline thin films prepared by plasma-enhanced chemical vapor deposition”, Materials Letters 41 (1999) 159.
43. B. H. Choi, H. B. Im, J. S. Song, K. H. Yoon, “Optical and electrical properties of Ga2O3-doped ZnO films prepared by r.f. sputtering”, Thin Solid Films 193-194 (1990) 712.
44. Y. Igasaki, H. Saito, “Substrate temperature dependence of electrical properties of ZnO:Al epitaxial films on sapphire (1 10)”, J. Appl. Phys. 69 (1991) 2190.
45. K. C. Park, D. Y. Ma, K. H. Kim, “The physical properties of Al-doped zinc oxide films prepared by RF magnetron sputtering”, Thin Solid Films 305 (1997) 201.
46. K. H. Kim, K. C. Park, D.Y. Ma, ” Structural, electrical and optical properties of aluminum doped zinc oxide films prepared by radio frequency magnetron sputtering”, J. Appl. Phys. 81 (1997) 7764.
47. J.-L. Chung, J.-C. Chen, C.-J. Tseng, “ Electrical and optical properties of TiO2-doped ZnO films prepared by radio frequency magnetron sputtering“, J. Phys. Chem. Solids. 69 (2008) 535.
48. J.- L. Chung, J.-C. Chen, C.-J. Tseng, “ The influence of titanium on the properties of zinc oxide films deposited by radio frequency magnetron sputtering“, Appl. Surf. Sci. 254 (2008) 2615.
49. C. G. Van de Walle, “Hydrogen as a Cause of Doping in Zinc Oxide”, Phys. Rev. Lett. 85 (2000) 1012.
50. C. G.. Van de Walle, J. Neugebauer, “Hydrogen as a Cause of Doping in Zinc Oxide”, Nature 423 (2003) 626.
51. L. Y. Chen, W. H. Chen, J. J. Wang, Franklin C. N. Hong, “ Hydrogen as a Cause of Doping in Zinc Oxide“, Appl. Phys. Lett. 85 (2004) 5628.
52. Y. Sun, W. Liu, Z. He, S. Liu, Z. Z. Yi, G. Du, “Novel properties of AZO film sputtered in Ar+H2 ambient at high temperature”, Vacuum 80 (2006) 981.
53. M. Katiyar, Y. H. Yang, J. R. Abelson, “Hydrogen-surface reactions during the growth of hydrogenated amorphous silicon by reactive magnetron sputtering: A real time kinetic study by in situ infrared absorption”, J. Appl. Phys. 77 (1995) 6247.
54. W.F. Liu, G. T. Du, Y. F. Sun, J. M. Bian, Y. Cheng, T. P. Yang, Y. C. Chang, Y. B. Xu, “Effects of hydrogen flux on the properties of Al-doped ZnO films sputtered in Ar+H2 ambient at low temperature”, Applied Surface Science 253 (2007) 2999.
55. S. Choopun, R. D. Vispute, W. Yang, R. P. Sharma, T. Venkatesan, H. Shen, “Realization of band gap above 5.0 eV in metastable cubic-phase MgxZn1-xO alloy films ”, Appl. Phys. Lett. 80 (2002) 1529.
56. J. Narayan, A. K. Sharma, A. Kvit, C. Jin, J. F. Muth, O. W. Holland, “Novel cubic ZnxMg1-xO epitaxial heterostructures on Si (100) substrate”, Solid State Communication 121 (2002) 9.
57. T. Minemoto, T. Negami, S. Nishiwaki, H. Takakura, Y. Hamakawa, “Preparation of Zn1-xMgxO films by radio frequency magnetron sputtering”, Thin Solid Films 372 (2000) 173.
58. M. N. Islam, T. B. Ghosh, K. L. Chopra, H. N. Acharya, “XPS and X-ray diffraction studies of aluminum-doped zinc oxide transparent conducting films”, Thin Solid Films 280 (1996) 20.
59. J. F. Moulder, W. F. Stickle, P. E. Sobol, K. D. Bomben, “Handbook of X-ray Photoelectron spectroscopy”, Physical Electronics, Inc., Eden Prairie, 1995, p. 231.
60. J. F. Moulder, W. F. Stickle, P. E. Sobol, K. D. Bomben, “Handbook of X-ray Photoelectron spectroscopy”, Physical Electronics, Inc., Eden Prairie, 1995, p. 232.
61. J. F. Moulder, W. F. Stickle, P. E. Sobol, K. D. Bomben, “Handbook of X-ray Photoelectron spectroscopy, Physical Electronics”, Inc., Eden Prairie, 1995, p. 231.
62. S. Kumar, V. Gupte, K. Sreenivas, “Structural and Optical Properties of magnetron sputtered MgxZn1-xO thin films”, J. Phys.: Condens. Matter. 18 (2006) 3343.