臺灣博碩士論文加值系統

在此論文中，我們藉由表面能調整，已成功定義出五環素有機薄膜電晶體(pentacene based-OTFTs)的主動區域。首先，利用自組裝單層膜(SAM)來作介電層的表面處理，並透過石英光罩照射UV光等方法，來加以控制所需區域的表面能。接著，在處理過的介電層表面沉積上pentacene薄膜後，只需經由簡易的去離子水浸洗過程，便能將照射過UV光部分的pentacene薄膜移除，而獲得所要的主動層區域。另外，藉由吸附能與侵入能的分析，我們可知此方法為一剝除機制，而介於pentacene薄膜、基板與去離子水間的不同侵入能，便是成功定義出主動區的關鍵因素。而我們所提出的此定義方式，亦可與傳統的黃光微影製程結合，製作出OTFTs陣列。
接著，我們將浸洗後獲得的pentacene區域製作成元件來驗證此方法的可行性。藉由元件特性的分析，我們觀察到其可靠度等特性依然優於傳統結構的對照元件，載子移動率、電流開/關比值以及次臨界擺幅等特性皆有明顯的改善。

In this thesis, the pentacene patterning by adjusting the surface energy was discussed. Firstly the surface energy was controlled by the self-assembled layer (SAM) treatment and the partial ultra-violet (UV) light exposure through quartz-glass mask. Then, after pentacene deposition, water dipping was used to remove the pentacene on UV-exposed area. The adhesion energy and the intrusion energy were analyzed to reveal that the dipping was a lift-off process and the key for successful patterning was the intrusion energy between pentacene, substrate (hydrophilic or hydrophobic) and the D.I. water. The proposed technology was compatible to conventional lithography system and is applicable to OTFT arrays.
Next, the remaining pentacene film was fabricated as a top-contact OTFTs to confirm the practicability of this technology. According to the output characteristics of OTFTs , the performance kept favorable and superior to that of the control sample. The mobility, the on/off current ratio (higher than 106) and the sub-threshold swing were also improved.

Chinese Abstract ………………………………………………………… Ι
English Abstract ………………………………………………………… II
Acknowledgement ……………………………………………………… IV
Contents ……………………………………………………… ………… V
Table Captions ……………………………………………………………VII
Figure Captions ………………………………………………………… VIII

Chapter 1. Introduction ………………………………………………… 1
1-1 Introduction of Organic Thin Film Transistors (OTFTs) ………………………… 1
1-2 Organic semiconducting materials …………………………………………… 4
1-3 Surface treatment ……………………………………………………………8
1-4 Operating mode of OTFTs ……………………………………………………9
1-5 Motivation …………………………………………………………………11
1-6 Thesis Organization …………………………………………………………12

Chapter 2. Device structures, fabrication and parameters extraction …13
2.1 Device structures and fabrication …………………………………………… 13
2.1-1 OTFTs with differential surface energy ………………………………… 13
2.1-2 OTFTs with patterned pentacene ……………………………………… 15
2.2 Methods of Device parameters extraction …………………………………… 18
2.2-1 Mobility …………………………………………………………… 18
2.2-2 Threshold voltage …………………………………………………… 19
2.2-3 On/Off current ratio ……………………………………………………19
2.2-4 Subthreshod swing …………………………………………………… 19
2.2-5 Surface free ……………………………………………………………20

Chapter 3. Result and Discussion ………………………………………… 21
3.1 Self-Assembly Monolayer (SAM) …………………………………………… 21
3.2 Surface energy control ……………………………………………………… 22
3.3 Pentacene patterning ………………………………………………………… 25

Chapter 4. Conclusion ………………………………………………………28

References ………………………………………………………………… 29
Tables ……………………………………………………………………… 35
Figures …………………………………………………………………… 38
Profile ……………………………………………………………………… 55

[1]. M. Pope and C.E. Swenberg, Electronic Processes in Organic Crystals and Polymers (Oxford University Press, New York, 1999).
[2] A. Tsumura, K. Koezuka, and T. Ando, “Macromolecular electronic devices: Field-effect transistor with a polythiophene thin film”, Appl. Phys. Lett. vol.49, pp. 1210, (1986).
[3]. D.F. Barbe and C.R. Westgate: Surface state parameters of metal-free phthalocyanine single crystals. J. Phys. Chem. Solids 31, 2679 (1970).
[4]. M.L. Petrova and L.D. Rozenshtein: Field effect in the organic semiconductor chloranil. Fiz. Tverd. Tela (Soviet Phys. Solid State) 12, 961 (1970).
[5]. M.L. Petrova and L.D. Rozenshtein: Field effect in the organic semiconductor chloranil. Fiz. Tverd. Tela (Soviet Phys. Solid State) 12, 961 (1970).
[6] A. Tsumura, K. Koezuka, and T. Ando, “Macromolecular electronic devices: Field-effect transistor with a polythiophene thin film”, Appl. Phys. Lett. vol.49, pp. 1210, (1986).
[7] J. H. Burroughes, C. A. Jones, and R. H. Friend, “Polymer diodes and transistors: new semiconductor device physics”, Nature, vol. 335, pp.137, (1988).
[8] A. Tsumura, K. Koezuka, and T. Ando, “Macromolecular electronic devices: Field-effect transistor with a polythiophene thin film”, Appl. Phys. Lett. Vol.49, pp. 1210, (1986)
[9]. F. Ebisawa, T. Kurokawa, and S. Nara: Electrical properties of polyacetylene-polysiloxane interface. J. Appl. Phys. 54, 3255 (1983).
[10]. A. Tsumura, K. Koezuka, and T. Ando: Macromolecular electronic device: Field-effect transistor with a polythiophene thin film. Appl. Phys. Lett. 49, 1210 (1986).
[11]. H. Shirakawa, E.J. Louis, A.G. MacDiarmid, C.K. Chiang, and A. Heeger: Synthesis of electrically conducting organic polymers: Halogen derivatives of polyacetylene, (CH)x. J. Chem. Soc. Chem. Commun. 00, 578 (1977).
[12] R. Smith, D. Allee, C. Moyer, and D, Loy, “Flexible Transistor Arrays”, SID 21, 18, (2005)
[13]. G. Horowitz, D. Fichou, X.Z. Peng, Z.G. Xu, and F. Garnier: A field-effect transistor based on conjugated alpha-sexithienyl. Solid State Commun. 72, 381 (1989).
[14]. C.W. Tang and S.A. van Slyke: Organic electroluminescent diodes. Appl. Phys. Lett. 51, 913 (1987).
[15]. J.H. Burroughes, D.D.C. Bradley, A.R. Brown, R.N. Marks, K. Mackay, R.H. Friend, P.L. Burns, and A.B. Holmes: Lightemitting diodes based on conjugated polymers. Nature 341, 539 (1990).
[16]. H.E. Katz: Organic molecular solids as thin film transistor semiconductors. J. Mater. Chem. 7, 369 (1997). 16. A.R. Brown, C.P. Jarrett, D.M. de Leeuw, and M. Matters: Fieldeffect transistors made from solution-processed organic semiconductors. Synth. Metal 88, 37 (1997).
[17]. F. Garnier: Thin-film transistors based on organic conjugated semiconductors. Chem. Phys. 227, 253 (1998).
[18]. G. Horowitz: Organic field-effect transistors. Adv. Mater. 10, 365 (1998).
[19]. C.D. Dimitrakopoulos and P.R.L. Malenfant: Organic thin film transistors for large area electronics. Adv. Mater. 14, 99 (2002).
[20] C. D. Dimitrakopoulos, D. J. Mascaro, “Organic thin-film transistors: a review of recent advances”, IBM J. Res. Dev 45, 11-27, (2001)
[21] C. Reese, M. Roberts, Mang-mang Ling, and Z. Bao, “Organic thin film transistors”, Materialstoday, Vol. 7, pp. 20-27, (2004)
[22] C.W. Chu, S.H. Li, C.W. Chen, V. Shrotriya, Y. Yang, “High-performance organic thin-film transistors with metal oxide/metal bilayer electrode” , Applied Physics Letters, Vol. 87, pp.193508, (2005)
[23] K. Puntambekar, J. Dong, G. Haugstad, C.D. Frisbie, “Structural and electrostatic complexity at a pentacene/insulator interface” , Adv. Funct. Mater, Vol.16, pp.679 (2006)
[24] M. Kawasaki, S. Imazeki, M. Ando, Y. Sekiguchi, S. Hirota, “High-resolution full-color LCD driven by OTFTs using novel passivation film”, IEEE Transactions on Electron Devices, Vol. 53, pp. 435- 441, (2006)
[25] K. Tsukagoshi, J. Tanabe, I. Yagi, K. Shigeto, “Organic light-emitting diode driven by organic thin film transistor on plastic substrates”, Journal of Applied Physics, Vol. 99, pp.064506
[26] Y. Y. Lin, D. J. Gundlach, S. F. Nelson, and T. N. Jackson, “Pentacene organic thin-film transistors-molecular ordering and mobility”, IEEE Electron Device Lett. vol. 18, pp. 87, (1997).
[27] C. D. Dimitrakopoulos and P. R. L. Malenfant, ”Organic thin film transistors for large area electronics”, Adv. Mater. (Weinheim, Ger.) 14, No. 2, pp.99, (2002).
[28]. L. Torsi, A. Dodabalapur, L. J. Rothberg, A. W. P. Fung, H.E. Katz,
“Performance Limits of Organic Transistors”, Science, 1996, P 1462.
[29]. H. E. Katz, C. Kloc, V. Sundar, J. Zaumseil, A. L. Briseno, Z. Bao, “Field-Effect Transistors made from Macroscopic Single Crystals of Teracene and Related Semiconductors on Polymer Dielectrics”, Journal of Material Research, Vol. 19, No. 7, Jul 2004, P 1995 - 1998.
[30]. C. D. Dimitrakopoulos, D. J. Mascaro, “Organic Thin-Film Transistors: A Review of Recent Advances”, IBM Journal of Research and Development, Vol. 45, No. 1, Jan 2001, P 11 - 27.
[31] Z. Bao, A. Dodabalapur, A. J. Lovinger, ”Soluble and processable regioregular poly(3-hexylthiophene) for thin film field-effect transistor applications with high mobility” Appl. Phys. Lett. Vol. 69, pp.4108, (1996)
[32] Y.Y. Lin, D. J. Gundlach, S. Nelson, T. N. Jackson, “Stacked pentacene layer organic thin-film transistors with improved characteristics”, IEEE Electron Device Lett, Vol. 18, pp.606, (1997).
[33] Yanming Sun, Yunqi Liu, and Daoben Zhu, “Advances in organic field-effect transistors”, J. Mater. Chem., vol. 15, pp. 53, (2005).
[34] G. M. Wang, J. Swensen, D. Moses, and A. J. Heeger, “Increased mobility from regioregular poly (3-hexylthiophene) field-effect transistors”, J. Appl. Phys, Vol 93, pp 6137, (2003)
[35] L. Sebastian, G. Weiser, and H. Bassler, “Charge transfer transitions in solid tetracene and pentacene studied by electroabsorption”, Chemical Physics, Vol 61, pp 125-135, (1981)
[36] E. A. Silinsh, and V.Capek, “Organic Molecular Crystals: Their Electronic States “, New York, (1980)
[37] Y. S. Yang, S. H. Kim, J. Lee, H.Y. Chu, L. Do, “Deep-level defect characteristics in pentacene organic thin films”, Applied Physics Letters, Vol. 80, pp. 1595-1597, (2002)
[38] H. Yanagisawa, T. Tamaki, M. Nakamura, K. Kudo, “Structural and electrical characterization of pentacene films on SiO2 grown by molecular beam” Thin Solid Films, Vol. 464-465, pp.398, (2004)
[39] D. Knipp, R. A. Street, A. Vo¨ lkel, J. Ho. “Pentacene thin film transistors on inorganic dielectrics: Morphology, structural properties, and electronic transport” Journal of Applied Physics, Vol. 93, pp.247, (2003)
[40] R. A. Street, D. Knipp, and A. R. V�匜kel, “Hole transport in polycrystalline pentacene transistors”, Appl. Phys. Lett., vol. 80, pp. 1658, (2002).
[41] G. Horowitz, “Organic field-effect transistors”, Adv. Mater., vol. 10, pp. 365, (1998).
[42] Y.-Y. Lin, D. J. Gundlach, S. F. Nelson, and T. N. Jackson, “Stacked pentacene layer organic thin-film transistors with improved characteristics”, IEEE Electron Device Lett, vol. 18, pp 606, (2000).
[43] S. F. Nelson, Y.-Y. Lin, D. J. Gundlach, and T. N. Jackson, “Temperature-independent transport in high-mobility pentacene transistors”, Appl. Phys. Lett., vol. 72, pp. 1854, (1998).
[44] O. Ostroverkhova, D. G. Cooke, S. Shcherbyna, R. F. Egerton, F. A. Hegmann, R. R. Tykwinski, and J. E. Anthony, “Bandlike transport in pentacene and functionalized pentacene thin films revealed by subpicosecond transient photoconductivity measurements”, Phys. Rev. B, vol. 71, pp. 035204, (2005).
[45] G. Nunes Jr., S. G. Zane, and J. S. Meth, “Styrenic polymers as gate dielectrics for pentacene field-effect transistors”, J. Appl. Phys., vol. 98, pp. 104503, (2005).
[46] M. McDowell, I. G. Hill, J. E. McDermott, S. L. Bernasek, and J. Schwartz, “Improved organic thin-film transistor performance using novel self-assembled monolayers”, Appl. Phys. Lett., vol. 88, pp. 073505, (2006).
[47]. R.H. Tredgold, Order in Thin Organic Films, Cambridge University Press, 1994.
[48] A. Ulman, An Introduction to Ultrathin Organic Films: From Langmuir-Blodgett to Self-Assembly, Academic press, New York, 1991.
[49]. R.F. Gould (Ed.), Contact Angle, Wettability and Adhesion, Proceeding of the 144th Meeting of the American Chemical Society, Vol. 43, Washington, DC, 1964.
[50]. R.J. Good, Contact angle wetting and adhesion: a critical review, in: K.L. Mimal (Ed.), Contact angle, Wettability and Adhesion, USP, The Netherlands, 1993, pp. 3–36.
[51] M. McDowell, I. G. Hill, J. E. McDermott, S. L. Bernasek, and J. Schwartz, Appl. Phys. Lett., Vol. 88, pp.073505 (2006)
[52] A. Inoue, T. Ishida, and N. Choi, Appl. Phys. Lett. 73,14 (1998)
[53] D. R. Hines, S. Mezhenny, M. Breban, and E. D. Williams, Appl. Phys. Lett. 86, 163101 (2005)
[54] Sung Hwan Kim, Hye Young Choi, Seung Hoon Han, Ji Ho Hur and Jin Jang, SID DIGEST Section 45.2 p.1297 (2004).
[55] Masahiko Ando, Masahiro Kawasaki, Shuji Imazeki, Hiroshi Sasaki, and Toshihide Kamata, Appl. Phys. Lett., Vol. 85, pp.1849 (2004)
[56] Wakana Kubo and Tetsu Tatsuma, Apply. Surf. Sci. 243 125 (2005)
[57] A. R. Brown, C. P. Jarrett, D. M. de Leeuw, and M. Matters, “Field-effect transistors made from solution-processed organic semiconductors”, Synth. Met., vol. 88, pp. 37, (1997).
[58] T. Torsi, “Novel applications of organic based thin film transistors”, Solid-State Elecronics, Vol 45, pp 1479-1485, (2001)
[59] Sung Hwan Kim, Hye Young Choi, Seung Hoon Han, Ji Ho Hur and Jin Jang, SID DIGEST Section 45.2 p.1297 (2004)
[60] C. D. Dimitrakopoulos, A. R. Brown, and A. Pomp, “Molecular beam deposited thin films of pentacene for organic field effect transistor applications”, J. Appl. Phys.,vol. 80, pp. 2501, (1996).
[61] Chih-Wei Chu, Sheng-Han Li, Chieh-Wei Chen, Vishal Shrotriya, and Yang Yang, “High-performance organic thin-film transistors with metal oxide/metal bilayer electrode”, Appl. Phys. Lett., vol. 87, pp. 193508, (2005).
[62] K N Narayanan Unni, Sylvie Dabos-Seignon, and Jean-Michel Nunzi, “Improved performance of pentacene field-effect transistors using a polyimide gate dielectric layer”, J. Phys. D: Appl. Phys.,vol. 38, pp. 1148, (2005).
[63] Kui-Xiang Ma, Chee-Hin Ho, Furong Zhu, and Tai-Shung Chung, “Investigation of surface energy for organic light emitting polymers and indium tin oxide”, Thin Solid Films, vol. 371, pp. 140, (2000)
[64] Surface, Interfaces, and Colloids；Drew Myers；New York, 1999.
[65] Fowkes, F. M. J Phys Chem 67, 2538. (1963)
[66] H Sugimura, N Saito, N Maeda, I Ikeda, Y Ishida, K Hayashi, L Hong, and O Takai, Nanotechnology 15 s69-s75(2004)
[67] Sang Yoon Yang, Kwonwoo Shin, and Chan Eon Park, Adv. Mater. 15,1806 (2005)
[68] D. H. Kaelble, J. of Applied Polymer Science 18, 1869 (1974).