Browse > Article
http://dx.doi.org/10.5370/JEET.2014.9.2.609

Effects of an Aluminum Contact on the Carrier Mobility and Threshold Voltage of Zinc Tin Oxide Transparent Thin Film Transistors  

Ma, Tae-Young (Dept. of Electrical Engineering, Gyeongsang National University)
Publication Information
Journal of Electrical Engineering and Technology / v.9, no.2, 2014 , pp. 609-614 More about this Journal
Abstract
We fabricated amorphous zinc tin oxide (ZTO) transparent thin-film transistors (TTFTs). The effects of Al electrode on the mobility and threshold voltage of the ZTO TTFTs were investigated. It was found that the aluminum (Al)-ZTO contact decreased the mobility and increased the threshold voltage. Traps, originating from $AlO_x$, were assumed to be the cause of degradation. An indium tin oxide film was inserted between Al and ZTO as a buffer layer, forming an ohmic contact, which was revealed to improve the performance of ZTO TTFTs.
Keywords
Zinc tin oxide; Transparent thin film transistors; Aluminium contact; Ohmic contact;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
연도 인용수 순위
1 N. L. Dehuff, E. S. Kettenring, D. Hong, H. Q. Chiang, J. F. Wager, R. L. Hoffman, C.-H. Park, and D. A. Keszler, "Transparent thin-film transistors with zinc indium oxide channel layer," J. Appl. Phys., Vol. 97, pp. 064505, 2005.
2 J. Liu, D. B. Buchholz, J. W. Hennek, R. Chang, A. Facchetti, and T. J. Marks, "All-Amorphous-Oxide Transparent, Flexible Thin-Film Transistors. Efficacy of Bilayer Gate Dielectrics," J. Am. Chem. Soc., Vol. 132, pp. 11934-11942, 2010.   DOI   ScienceOn
3 A. Dey, D. R. Allee, and L. T. Clark, "Impact of drain bias stress on forward/reverse mode operation of amorphous ZIO TFTs," Solid State Electron., Vol. 62, pp. 19-24, 2011.   DOI   ScienceOn
4 K. Nomura, H. Ohta, A. Takagi, T. Kamiya, M. Hirano, and H. Hosono, "Room-temperature fabriccation of transparent flexible thin-film transistors using amorphous oxide semiconductors," Nature, Vol. 432, pp. 488-492, 2003.
5 J. S. Park, W. Maeng, H. Kim, and J. Park, "Review of recent developments in amorphous oxide semiconductor thin-film transistor devices," Thin Solid Films, Vol. 520, pp. 1679-1693, 2011.
6 M. Fakhri, P. Gorrn, T. Weimann, P. Hinze, T. Riedl, "Enhanced stability against bias-stress of metal-oxide thin film transistors deposited at elevated temperatures," Applied Phys. Lett., Vol. 99, pp. 123503, 2011.   DOI   ScienceOn
7 M. K. Ryu, S. Yang, S. K. Park, C. Hwang, and J. K. Jeong, "Impact of Sn/Zn ratio on the gate bias and temperature-induced instability of Zn-In-Sn-O thin film transistors," Applied Phys. Lett., Vol. 95, pp. 173508, 2009.   DOI   ScienceOn
8 S. Lee, J. Bang, W. K., H. Uhm, and J. Park, "Effects of additive hydrogen gas on the instability due to air exposure in ZnO-based thin film transistors," Thin Solid Films, Vol. 520, pp. 1479-1483, 2011.   DOI   ScienceOn
9 S. Masuda, K. Kitamura, Y. Okumura, S. Miyatake, H. Tabata, and T. Kawai, "Transparent thin film transistors using ZnO as an active channel layer and their electrical properties," J. Appl. Phys., Vol. 93, pp. 1624-1630, 2003.   DOI   ScienceOn
10 K. Abe, N. Kaji, H. Kumomi, K. Nomura, T. Kamiya, M. Hirano, and H. Hosono, "Simple Analytical Model of On Operation of Amorphous In-Ga-Zn-O Thin-Film Transistors," IEEE Trans., Vol. ED-58, pp. 3463-3471, 2011.
11 P. Gorrn, M. Lehnhardt, T. Riedl, and W. Kowalsky, "The influence of visible light on transparent zinc tin oxide thin film transistors," Appl. Phys. Lett., Vol. 91, pp. 193504, 2007.   DOI   ScienceOn
12 H. Q. Chiang, J. F. Wager, R. L. Hoffman, J. Jeong, and D. A. Keszler, "High mobility transparent thinfilm transistors with amorphous zinc tin oxide channel layer," Appl. Phys. Lett., Vol. 86, pp. 013503, 2005.   DOI   ScienceOn
13 C. N. Cha, M. H. Choi, and T. Y. Ma, "Highly transparent and resistive nanocrystalline ZnO-$SnO_2$ films prepared by rf magnetron sputtering," J. Electr. Eng. Technol., Vol. 7, pp. 596-560, 2012.   과학기술학회마을   DOI   ScienceOn
14 D. Natali, L. Fumagalli, and M. Sampietro, "Modeling of organic thin film transistors: Effect of contact resistances." J. Appl. Phys., Vol. 101, pp. 014501, 2007.   DOI   ScienceOn
15 T. Y. Ma, "The effects of oxygen partial pressure and post-annealing on the properties of ZnO-$SnO_2$ thin film transistors," J. KIEEME, Vol. 25, pp. 304-308, 2012.   과학기술학회마을   DOI   ScienceOn
16 D. K. Schroder, "Semiconductor Material and Device Characterization," 1st ed., New York: A Wiley-Interscience publication, 1990, pp. 183.
17 D. K. Schroder, "Semiconductor Material and Device Characterization," 1st ed., New York: A Wiley-Interscience publication, 1990, pp. 226.
18 S. Lee, H. Park, and D. C. Paine, "The effect of metallization contact resistance on the measurement of the field effect mobility of long-channel unannealed amorphous In-Zn-O thin film transistors," Thin Solid Films, Vol. 520, pp. 3769-3773, 2012.   DOI   ScienceOn
19 A. Ahnood, K. Ghaffarzadeh, A. Nathan, P. Servati, F. Li, M. R. Esmaeili-Rad, A. Sazonov, "Non-ohmic contact resistance and field-effect mobility in nanocrystalline silicon thin film transistors," Appl. Phys. Lett., Vol. 93, pp. 163503, 2008.   DOI   ScienceOn
20 K. Jacobi, G. Zwicker, A. Gutmann, "Work function, electron affinity and band bending of zinc oxide surfaces," Surf. Sci., Vol. 141, pp. 109-125, 1984.   DOI   ScienceOn
21 M. N. Islam, and M. O. Hakim, "Electron affinity and work function of polycrystalline $SnO_2$ thin film," J. Mater. Sci. Lett., Vol. 5, pp. 63-65, 1986.   DOI
22 A. K. M. Ahsan and D. K. Schroder, "Impact of postoxidation annealing on low-frequency noise, threshold voltage, and subthreshold swing of p-channel MOSFETs," IEEE Electron Device Lett., Vol. 25, pp. 211-213, 2004.   DOI   ScienceOn
23 W. E. Spicer, S. Eglash, I. Lindau, C. Y. Su, and P. R. Skeath, "Development and confirmation of the unified model for Schottky barrier formation and MOS interface states on III-V compounds," Thin Solid Films, Vol. 89, pp. 447-460, 1982.   DOI   ScienceOn
24 S. Lee, J. Park, K. Jeon, S. Kim, Y. Jeon, D. H. Kim, D. M. Kim, J. C. Park, and C. J. Kim, "Modeling and characterization of metal-semiconductor-metal-based source-drain contacts in amorphous InGaZnO thin film transistors," Appl. Phys. Lett., Vol. 96, pp. 113506, 2010.   DOI   ScienceOn
25 K. C. Kao, and W. Hwang, "Electrical Transport in Solid," 1st ed., New York: Pergamon Press Inc., 1981, pp. 101-110.
26 P. Richman, "MOS Field-Effect Transistors and Integrated Circuit," 1st ed., New York: A Wiley- Interscience publication, 1973, pp. 94-96.
27 M. Kimira, Y. Kamada, S. Fujita, T. Hiramatsu, T. Matsuda, M. Furuta, and T. Hirao, "Mechanism analysis of photoleakage current in ZnO thin-film transistors using device simulation," Appl. Phys. Lett., Vol. 97, pp. 163503, 2010.   DOI   ScienceOn
28 B. G. Streetman, "Solid State Electronic Devices," 6th ed., New York: Prentice Hall International Inc., 1990, pp. 144.
29 K. C. Kao, and W. Hwang, "Electrical Transport in Solid," 1st ed., New York: Pergamon Press Inc., 1981, pp. 146.
30 Z. Yuan, X. Zhu, X. Wang, X. Cai, B. Zhang, D. Qiu, and H. Wu, "Annealing effects of $In_2O_3$ thin films on electrical properties and application in thin film transistors," Thin Solid Films, Vol. 519, pp. 3254-3258, 2011.   DOI   ScienceOn