本研究包含兩個部分，第一個部分為製作摻雜TiO2奈米粉體之High-k有機無機複合絕緣層。我們首先確認有機絕緣層高分子材料PVP與其橋接劑PMCF之最佳混合比例，以製作出介電常數較高之有機絕緣層。而後我們摻雜TiO2奈米粉體於有機絕緣層，並改變TiO2奈米粉體之摻雜濃度。分析其電性表現，我們發現摻雜3 vol% TiO2奈米粉體之複合絕緣層具有較高的介電常數與較佳之漏電流控制。
本研究的第二個部分為摻雜3 vol% TiO2奈米粉體複合絕緣層之表面平坦化處理。我們嘗試三種不同的表面處理方式：(1) 化學機械研磨 (2) 覆蓋緩衝層 (3) 化學機械研磨後再覆蓋緩衝層。經由實驗分析，我們發現複合絕緣層經由化學機械研磨後再覆蓋緩衝層之方式可得到最佳的效果。我們在此經過改善過後之複合絕緣層上，蒸鍍pentacene主動層以製作OTFTs元件。最後我們成功地製作出載子遷移率0.58 cm2/ Vs，臨界電壓 -4.3 V，以及開關電流比為6×103之OTFTs元件。

This study consists of two parts. In the first part, we intend to fabricate high-k organic-inorganic composite dielectrics. First of all, we attempt to discover the best blending proportion of the cross-linking agent PMCF to PVP for fabricating organic polymer dielectrics of higher dielectric constant. Then we blend TiO2 nanoparticles into organic polymer dielectrics and adjust the concentration of blended TiO2 nanoparticles. By analyzing the electric performance, we find the composite dielectrics with 3 vol% TiO2 nanoparticles blended shows higher dielectric constant and lower leakage current.
In the second part, we apply surface treatment to the composite dielectrics with 3 vol% TiO2 blended. We apply three methods of surface treatment : (1) Chemical Mechanical Polishing, CMP (2) Buffer layer (3) CMP + Buffer layer. We find that the composite dielectrics treated by CMP + Buffer layer performs best after analyzing the effect of the three methods of surface treatment. Then we deposit pentacene on the composite dielectrics of best performance by thermal deposition process to demonstrate OTFTs. We eventually demonstrate high performance OTFTs of mobility 0.58 cm2/ Vs, Vth -4.3 V, and on-off ratio 6×103.

[1] Fang-Chung Chen, Chiao-Shun Chuang, Yung-Sheng Lin, Li-Jen Kung, Tung-Hsien Chen, Han-Ping D. Shieh, "Low-voltage organic thin-film transistors with polymeric nanocomposite dielectrics, " Organic Electronics 7 (2006) 435–439
[2] J.H. Schan. et. al. "On the Intrinsic Limits of Pantacene Fieldeffet
Transistors", Organic Electronic, Vol. 1, No. 1, p.57.
[3] Gilles Horowitz, "Organic Field-Effect Transistors" Adv. Mater., No.5, 10, (1998)
[4] C. D. Dimitrakopoulos, and D. J. Mascaro, “Organic thin-film 2) Henning Sirrintransistors: A review of recent advances,” IBM J. RES. & DEV.2001, VOL. 45, NO. 1.
[5] 施敏，"半導體元件物理與製作技術" ，國立交通大學出版社，2002
[6] Christos D. Dimitrakopoulos, and Patrick R. L. Malenfant, “Organic Thin Film Transistors for Large Area Electronics,” Adv. Mater. 2002, 14, No. 2
[7] A. Tsumura, H. Koezuka and T. Ando, “Macromolecular electronic device:field-effect transistor with a polythiophene thin film”, Appl. Phys. Lett. 49,1210 (1986).
[8] H. Koezuka, A. Tsumura, and T. Ando, “Soluble and processable regioregular poly(3-hexylthiophene) for thin film field-effect transistor applications with high mobility”, Synth. Met. 18, 699 (1987).
[9] H. Koezuka, A. Tsumura, and T. Ando, “Soluble and processable regioregular poly(3-hexylthiophene) for thin film field-effect transistor applications with high mobility”, Synth. Met. 18, 699 (1987).
[10] M. Baldo, M. Deutsch, P. Burrows, H. Gossenberger, M. Gerstenberg, V. Ban, and S. Forrest, "Organic Vapor Phase Deposition" Adv. Mater. 10, No. 18, (1998)4. Semiconductor Devices Physics and Technology/S.M. SZE
[11] Peter V. Necliudov, Michael S. Shur , David J. Gundlach, Thomas N. Jackson, ”Contact resistance extraction in pentacene thin film transistors” Solid-State Electronics, 47, pp.259-262, (2003)
[12] Donald A. Neamen,” Fundamentals of Semiconductor Physics and Devices”, 3rd ed., McGraw Hill, (2005)
[13] N. Koch, A. Kahn, J. Ghijsen, J.-J. Pireaux, J. Schwartz, R. L. Johnson, and A. Elschner, “Conjugated organic molecules on metal versus polymer electrodes: Demonstration of a key energy level alignment mechanism” Appl. Phys. Lett., Vol.82, pp.70-73, (2003).
[14] E. M. Suuberg, “Vapor pressures and enthalpies of solution of polycyclic aromatic hydrocarbons and theirderivatives,＂ J. Chem. Eng. Data, vol.43, no. 3, pp.486–492, 1998.
[15] Frank-J. Meyer zu Heringdorf, M. C. Reuter & R. M. Tromp, “Growth dynamics of pentacene thin films” IBM T.J. Watson Research Center, Yorktown Heights, PO Box 218, New York 10598, USA
[16] Sandra E. Fritz, Stephen M. Martin, C. Daniel Frisbie, Michael D. Ward, ”Structural Characterization of a Pentacene Monolayer on an Amorphous SiO2 Substrate with Grazing Incidence X-ray Diffraction” J. AM. CHEM. SOC. 9 Vol.126, No.13, (2004)
[17] Iwao Yagi, Kazuhito Tsukagoshia, Yoshinobu Aoyagi, ”Growth control of pentacene films on SiO2/Si substrates towards formation of flat conduction layers” Thin Solid Films, 467, pp.168-171, (2004)
[18] Donald.L Smith, ”Thin-film deposition , principles and practice” , McGraw-Hill, Inc
[19] E. M. Conwell, “Impurity Band Conduction in Germanium and Silicon,” Phys. Rev. 103, 51 (1956).
[20] N. F. Mott, Canadian J. Phys. 34, 1356 (1956).
[21] P. G. Le Comber and W. E. Spear,＂ Electronic Transport in Amorphous Silicon Films,＂ Phys. Rev. Lett., Vol. 25, pp. 509-511, 1970.
[22] Kyunghee Choi, D. K. Hwang, Kimoon Lee, Jae Hoon Kim, and Seongil Im, ”Pentacene Thin-Film Transistors with Polymer/TiOx Double-Layer Dielectrics Operating at 3V” Electrochemical and Solid-State Letters, 10, pp.114-116, (2007)
[23] A.L. Deman , J. Tardy, ” Stability of pentacene organic field effect transistors with a low-k polymer/high-k oxide two-layer gate dielectric” Materials Science and Engineering, pp.421-426, (2006)
[24] R. J. H. Clark, “The chemistry of titanium and vanadium”, Elsevier, Amsterdam(1968).
[25] P. Villars and L.D. Calvert, “Pearson's handbook of crystallographic data for intermetallic phases”, ASM International, Materials Park (1991)
[26] A. J. Moulson, J. M. Herbert, “Electroceramics”, Chapman & Hall, London (1990).
[27] M.A. Fury, “Chemical Mechanical Planarization of Aluminum-Based Alloys for MultilevelMetallization,“ Solid state Technology, Vol. 20,1995, pp.61-69.
[28] 王建榮，林必窕，林慶福 編譯，”半導體平坦化CMP 技術”。
[29] R. Jairath, M. Desai, M. Stell, R. Tolles, and D. Scherber Brewer,Mat. Res. Soc. Symp. Proc., 337, 121 (1994).
[30] Chi-Hwan Kim; Jin-Hyuk Bae; Sin-Doo Lee; Jong Sun Choi School of Electrical Engineering, Seoul National University, Seoul, Koreab School of Electronics and Electrical Engineering, Hongik University, Mapo-gu,Seoul, Korea,” Fabrication of Organic Thin-Film Transistors Based onHigh Dielectric Nanocomposite Insulators” Mol. Cryst. Liq. Cryst., Vol. 471, pp. 147–154, 2007
[31] Kunjithapatham Sethuraman, Shizuyasu Ochiai, Kenzo Kojima, and Teruyoshi Mizutani, ” Performance of poly(3-hexylthiophene) organic field-effect transistors on cross-linked poly(4-vinyl phenol) dielectric layer and solvent effects” , APPLIED PHYSICS LETTERS 92, 183302 (2008)
[32] Sang Yoon, Kwonwoo Shin,Chan Eon Park,”The Effect of Gate-Dielectric Surface Energy on Pentacene Morphology and Organic Field-Effect Transistor Characteristics” ,Adv. Funct. Master. 2005, 15, 1806-1814
[33] Soeren Steudel, Stijn De Vusser, Stijn De Jonge, Dimitri Janssen, Stijn Verlaak, Jan Genoe, and Paul Heremans, “Influence of the dielectric roughness on the performance of pentacene transistors” , Appl. Phys. Lett., Vol. 85, No. 19, 8 November 2004
[34] Ricardo Ruiz, Alexios Papadimitratos, “Thickness Dependence of Mobility in Pentacene Thin-Film Transistors” Adv. Mater.,17, pp.1795-1798, (2005)