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Structural and electrical characteristics of IZO thin films with deposition temperature  

Jun, D.G. (Dept. of Materials Engineering, Korea University of Technology and Education)
Lee, Y.L. (Dept. of Materials Engineering, Korea University of Technology and Education)
Lee, K.M. (Dept. of Materials Engineering, Korea University of Technology and Education)
Publication Information
Journal of the Semiconductor & Display Technology / v.10, no.3, 2011 , pp. 67-74 More about this Journal
Abstract
In this study, we have investigated the effect of the substrate temperature on the structural and the electrical characteristics of IZO thin films for the OLED (organic light emitting diodes) devices. For this purpose, IZO thin films were deposited by RF magnetron sputtering under various substrate temperature. The substrate temperature has been changed from room temperature to $400^{\circ}C$. Samples which were deposited under $250^{\circ}C$ show amorphous structure. The electrical resistivity of crystalline-IZO (c-IZO) film was higher than that of amorphous-IZO (a-IZO) film. And the electrical resistivity showed minimum value near $150^{\circ}C$ of deposition temperature. The OLED device was fabricated with different IZO substrates made by configuration of IZO/$\acute{a}$-NPD/DPVB/$Alq_3$/LiF/Al to elucidate the performance of IZO substrate. OLED devices with the amorphous-IZO (a-IZO) anode film show better current density-voltage-luminance characteristics than that of OLED devices with the commercial crystalline-ITO (c-ITO) anode film. It can be explained that very flat surface roughness and high work function of a-IZO anode film lead to more efficient hole injection by reduction of interface barrier height between anode and organic layers. This suggests that a-IZO film is a promising anode materials substituting conventional c-ITO anode in OLED devices.
Keywords
deposition temperature; IZO thin film; OLED; RF-magnetron sputtering;
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Times Cited By KSCI : 5  (Citation Analysis)
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1 H. Kim, C. M. Gilmore, J. S. Horwitz, A. Piqué, H. Murata, G. P. Kushto, R. Schlaf, Z. H. Kafafi, and D. B. Chrisey, "Transparent conducting aluminum-doped zinc oxide thin films for organic light-emitting devices", Applied Physics Letters, 76, pp.259-261 (2000).   DOI   ScienceOn
2 박창하, 이학준, 김현범, 김동호, 이건환, "DC 마그네 트론 스퍼터링을 이용한 IZO 박막의 제조와 특성 연 구", Journal of Korean Institute of Surface Engineering, 38, pp.188-192 (2005).
3 Kenji Nomura, Toshio Kamiya, Hiromichi Ohta, Kazushige Ueda, Masahito Hirano, and Hideo Hosono, "Carrier transport on transparent oxide semiconductor with intrinsic structural randomness probed using singlecrystalline $InGaO_3(ZnO)_5$ films", Applied Physics Letters, 85, pp.1993-1995 (2004).   DOI   ScienceOn
4 Akihiro Takagi, Kenji Nomura, Hiromichi Ohta, Hiroshi Yanagi, Toshio Kamiya, Masahiro Hirano, and Hideo Hosono, "Carrier transport and electronic structure in amorphous oxide semiconductor, a- $InGaZnO_4$", Thin Solid Films, 486, pp.38-41 (2005).   DOI   ScienceOn
5 노경현, 최문구, 박승한, 주홍렬, "비정질 투명전도막 In2O3:Zn의 전기적 광학적 특성", Hankook Kwanghan Hoeji, 13, pp.455-459 (2002).
6 N. Ito, Y. Sato, P.K. Song, A. Kaijio, K. Inoue, and Y. Shigesato, "Electrical and optical properties of amorphous indium zinc oxide films", Thin Solid Films, 496(1), pp.99-103 (2006).   DOI   ScienceOn
7 Hunang Wen Hao, A. M. Baro, and J. J. Saenz, "Electrostatic and contact forces in force microscopy", 9(2), pp.1323-1328 (1991).
8 C. Nunes de Carvalho, A. M. Botelho do Rego, A. Amaral, P. Brogueira and G. Lavareda, "Effect of substrate temperature on the surface structure, composition and morphology of indium-tin oxide films", Surface and Coatings Technology, 124, pp. 70-75 (2000).   DOI   ScienceOn
9 김화민, 김종재, "마그네트론 스퍼터링 방법으로 제작된$In_2O_3$-ZnO 박막의 전기적 특성에 대한 열처리 효과", Journal of the Korean Vacuum Society, 14, pp.238-244, (2005).
10 박영란, 김용성, "In 도핑된 ZnO 박막의 투명 전극과 유기 발광 다이오드 특성", Journal of the Korean Ceramic Society, 44(6), pp.291-343, (2007).   DOI
11 Han-Ki Kim, D.-G. Kim, K.-S. Lee, M.-S. Huh, S. H. Jeong, K. I. Kim, and Tae-Yeon Seong, "Plasma damage- free sputtering of indium tin oxide cathode layers for top-emitting organic light-emitting diodes", Applied Physics Letters, 86(18), pp. 183503-183505 (2005).   DOI   ScienceOn
12 Y. Hoshi, H. Kato, and K. Funatsu, "ITO films deposited by facing target sputtering", J. mat. sci., 18, pp. 359-362 (2003).
13 배정혁, 문종민, 김한기, "박스 캐소드 스퍼터로 성장 시킨 전면 발광 OLED용 상부 InZnO 캐소드 박막의 전기적, 광학적, 구조적 특성 연구", Journal of Korean Institute of Electrical and Electronic Material Engineers, 19(5), pp.442-449 (2006).   DOI
14 K. Ishibashi, K. Hirata, and N. Hosokawa, "Mass spectrometric ion analysis in the sputtering of oxide targets", J.Vac. Sci. Technol. A, 10, pp.1718-1722 (1992).   DOI
15 K. Tominaga, T. Ueda, T. Ao, M. Kataoka, and I. Mori, "TO films prepared by facing target sputtering system", Thin Solid Films, 281-282, pp. 194-197 (1996).   DOI   ScienceOn
16 N. Taga, M. Maekawa, Y. Shigesato, I. Yasui, M. Kamei and T. E. Haynes, "Deposition of Heteroepitaxial $In_2O_3$ Thin Films by Molecular Beam Epitaxy", Jpn. J. Appl.Phys. 37,pp.6524-6529 (1998)   DOI
17 D. C. Paine, B. Yaglioglu, "Amorphous IZO-based transparent thin film transistors", Thin solid films 516, pp.5894-5898 (2007)
18 H.-K. Kim, D.-G. Kim, K.-S. Lee, M. S. Huh, S. H. Jeong, and K. I. Kim, "The Application of Anode Material (ITAZO) and Hole Transportation Material (NiO) in Organic Solar Cell", 1. Photonics and Optoelectronics 2009, pp.1-4 (2005).
19 노경현, 최문구, 박승환, 주홍렬, 정창오, 정규하, 박장우, "비정질 투명전도막 $In_2O_3$:Zn의 전기적 광학적 특성", 한국광학회지, 13, pp.455-459 (2002).