本研究以電沉積法製備氧化鎢電致色變薄膜，將氧化鎢沉積在可撓性塑膠基板上來製備成可撓性顯示器。本研究主要分為三個部分進行，第一部分測試電沉積法鍍膜及著去色電位之最佳參數，並探討張應力、壓應力、彎曲次數、彎曲半徑、溫度對於電致色變薄膜記憶保持能力的影響，進而探討其薄膜的穿透率、穿透率差、著色效率，再觀察其薄膜表面形貌、粗糙度，最後使用電壓-電流來對電致色變薄膜進行電性量測。第二部分為利用Light tools光學模擬工具來進行模擬薄膜不同參數下的穿透率改變，並使用Color chart來量化模擬結果。第三部分為將可撓性電致色變顯示元件封裝，將進行其電路結構設計並製作完成。經由本實驗所量測得到的最佳薄膜沉積參數為2 V沉積電位條件沉積1分鐘，所得到之薄膜厚度約為400 nm，表面粗糙度介於7-12 nm間；氧化鎢薄膜最佳的著去色電位為2.5 V，其穿透率差在650 nm時達到80%，而著色效率可達100 cm2/coul；氧化鎢薄膜著色記憶保持能力為兩個小時，受到張應力固定彎曲半徑15 mm及10 mm記憶保持能力分別為1小時及4 分鐘、受壓應力固定彎曲半徑15 mm及10 mm記憶保持能力皆為1小時、受溫度效應的影響40℃及60℃記憶保持能力皆為1小時，著色記憶保持能力受到張應力彎曲次數會隨著次數增加而衰退，而受壓應力彎曲次數則因薄膜破裂已達其極限其著色記憶保持能力結果衰退致最差；漏電流也會因為張應力、壓應力及溫度效應的影響會使得漏電流越來越高。

In this study, electrodeposition method was used to fabricate tungsten oxide electrochromic thin film. Tungsten oxide film was electrodeposited on plastic substrate to make the electrochromic display device. The experiments of this study were divided into three parts. The first part tested the best parameter of electrodeposition, coloration and bleaching, and discussed self-bleaching memory retention of electrochromic film under tension, compression, bending cycles, bending radius and temperature effect, and then investigated transmittance, delta transmittance and color efficiency, and observed surface morphology and roughness of films. Electronic properties of electrochromic film were tested by voltage-current. Second part, the color of films was simulated by light tools under different parameters, and the simulated results were defined by color chart. Last part, the packaged flexible electrochromic display device and the designed electric circuit were completed. The best parameter of voltage was 2V, and deposited time was 1 min in the experiment. The thickness of tungsten oxide was 400 nm, and the roughness of film was between 7 to 12 nm. The best parameter of coloration/bleaching voltage was 2.5 V. The delta transmittance and color efficiency of tungsten oxide film were 80% at 650 nm and 100 cm2/coul. The self-bleaching memory retention was 2 hours, and it was 1 hour and 4 minutes under the bending radius of 15 mm and 10 mm by tension, and it was both 1 hour under the bending radius of 15 mm and 10 mm by compression. The self-bleaching memory retention was both 1 hour at 40℃ and 60℃. The self- bleaching memory retention was declined with the increased bending cycles by tension, and it down to the worst because the film was broken under bending cycles by compression. The leakage current will be increased under the effect of tension, compression, temperature.

[1] http://windows.lbl.gov/comm_perf/Electrochromic/electroSys-cec.htm
[2] F. Beck, M. Dahlhaus and J. Appl, Electrochromic coatings for smart windows, Surface Science, Vol.23, pp.1127-1131 (1993).
[3] C. G. Granqvist, Oxide electrochromics: Why, how, and whither, Solar Energy Materials & Solar Cells, Vol.92, pp.203-208(2008).
[4] http://www.riteksolar.com/tc/p2-solar_modules-4.asp
[5] http://technews.tw/2013/12/11/apple-patents-tech-for-making-curved-touch-surfaces-displays/
[6] http://www.youtube.com/watch?v=S34bQj_jTGU
[7] http://www.ctimes.com.tw/DispNews/tw/1211132349KF.shtml
[8] 曾俊元，高效能軟性之全固態薄膜型電致變色元件系統開發(I)，國科會/經濟部能源局102年度能源科技學術研討暨成果發表會精簡報告。
[9] 李坤穆，軟性敏化太陽電池面臨的挑戰，工業材料，124-132 (2010)。
[10] http://www.cas.cn/kxcb/kpwz/201105/t20110512_3131838.shtml
[11] C.G. Granqvist, Handbook of Inorganic Electrochromic Material, Elsevier, Amsterdam, (1995).
[12] J. Livage, D. Ganguli, Sol-gel electrochromic coatings and devices: Areview, Solar Energy Materials & Solar Cells, Vol.68, pp. 365-381(2001).
[13] E. Lassner and W.D. Schubert. Tungsten: Properties, Chemistry, Technology of the Element, Alloys, and Chemical Compounds. New York: Kluwer Academic, 1999.
[14] K. Bange, Colouration of tungsten oxide films: A model for optically active coatings, Solar Energy Materials & Solar Cells, 58 (1999) 1-131.
[15] B. W. Faughnan, R. S. Crandall, P. M. Heyman, Electrochromism in WO3 Amorphous, RCA Review, Vol 36, pp.177-197 (1975).

[16] S. H. Lee, H. M. Cheong, J. G. Zhang, A. Mascarenhas, D. K. Benson, S. K. Deb, Electrochromic mechanism in a-WO3-y thin films, Appl. Phys. Letters, Vol.74, pp. 242-244 (1999).
[17] M. Deepa, D. P. Singh, S. M. Shivaprasad, S. A. Agnihotry, Acomparison of electrochromic properties of sol-gel derived amorphous and nanocrystalline tungsten oxide films, Current Applied Physics, pp. 220-229, (2007).
[18] C. P. Cheng, Y. Kuo, C. P. Chou, C. H. Cheng, T. P. Teng, Performance improvement of electrochromic display devices employing micro-size precipitates of tungsten oxide, Appl. Phys. A, Vol.116, pp.1553-1559 (2014).
[19] J.L. He & M.C. Chiu, Effect of oxygen on the electrochromism of RF reactive magnetron sputter deposited tungsten oxide, Surface and Coatings Technology, Vol. 127, pp. 43-51 (2000).
[20] P. V. Ashrit, Dry lithiation study of nanocrystalline, polycrystalline and amorphous tungsten trioxide thin-films, Thin Solid Films, Vol. 385, pp. 81-88 (2001).
[21] J. Zhang, X.L. Wang, X.H. Xia, C.D. Gu, Z.J. Zhao, J.P. Tu, Enhanced electrochromic performance of macroporous WO3 films formed by anodic oxidation of DC-sputtered tungsten layers, Electrochimica Acta, Vol. 55, pp. 6953-6958 (2010).
[22] C. Bechinge, H Mufer, C Schafle, O. Sundberg, P. Leiderer, Submicron metal oxide structures by a sol-gel process on patterned substrates, Thin Solid Films, Vol. 366, pp. 135-138 (2000).
[23] F. Beck, M. Dahlhaus and J. Appl, Electrochromic coatings for smart windows, Surface Science, Vol. 23, pp. 1127-1131 (1993).

[24] A.K. Chawla, S. Singhal, H.O. Gupta, R. Chandra, Effect of sputtering gas on structural and optical properties of nanocrystalline tungsten oxide films, Thin Solid Films, Vol. 517, pp. 1042-1046 (2008).
[25] C. Trimble, M.D. Vries, J.S. Hale, D.W. Thompson, T.E. Tiwald, J.A. Woollam, Infrared emittance modulation devices using electrochromic crystalline tungsten oxide, polymer conductor, and nickel oxide, Thin Solid Films, Vol. 355, pp. 26-34 (1999).
[26] A. Subrahmanyam, A. Karuppasamy, Optical and electrochromic properties of oxygen sputtered tungsten oxide (WO3) thin film, Solar Energy Materials & Solar Cells, Vol 91, pp. 266-274 (2007).
[27] Y. S. Lin, Y. L. Chiang, J. Y. Lai, Effects of oxygen addition to the electrochromic properties of WO3−z thin films sputtered on flexible PET/ITO substrates, Solid State Ionics, Vol.180, pp.99–105 (2009).
[28] S. A. Agnihotry, Rashmi, R. Ramchandran, S. Chandra, Pre-existence of HxWO3 in e-beam deposited WO3 films, Solar Energy Materials & Solar Cells, Vol. 36, pp. 289-294 (1995).
[29] J. L. Solisa, A. Hoel, V. Lantto, C. G. Granqvist, Infrared spectroscopy study of electrochromic nanocrystalline tungsten oxide films made by reactive advanced gas deposition, J. Appl. Phys., Vol. 89, pp. 2727-2732 (2001).
[30] D. Gogova, L. K.Thomas & B. Camin, Comparative study of gasochromic and electrochromic effect in thermally evaporated tungsten oxide thin films, Thin Solid Films, Vol. 517, pp. 3326-3331 (2009).
[31] P. K. Biswas, N. C. Pramanik, M. K. Mahapatra, D. Ganguli, J. Livage, Optical and electrochromic properties of sol-gel WO3 films on conducting glass, Materials Letters, Vol. 57, pp. 4429-4432 (2003).
[32] R. Solarska, B. D. Alexander, J. Augustynski, Electrochromic and structural characteristics of mesoporous WO3 films prepared by a sol-gel method, Journal of Solid State Electrochem, Vol. 8, pp. 748-755 (2004).
[33] I. Karakurt, J. Boneberg, P. Leiderer, Electrochromic switching Of WO3 nanostructures and thin films, Appl. Phys. A, Vol. 83, pp. 1-3 (2006).
[34] O. Pyper, R. Schollhorn1, J. J. T. M. Donkers, L. H. M. Krings, Nanocrystalline structure of WO3 thinfilms prepared by the sol-gel technique, Materials Research Bulletin, Vol. 33, pp. 1095-1101 (1998).
[35] M .G. Hutchins, N. A. Kamel, N. E. Kadry, A. A. Ramadan, K. Abdel-Hady, Preparation and Propertiesof Electrochemically Deposited Tungsten Oxide Films, Phys. stat. sol. (a), Vol. 175, pp. 991-1002 (1999).
[36] C. G. Granqvist, Electrochromic tungsten oxide films Review of progress 1993–1998, Solar EnergyMaterials & Solar Cells, Vol. 51, pp. 201-262 (2000).
[37] S. H. Lee, H. M. Cheong, J. G. Zhang, A. Mascarenhas, D. K. Benson, S. K. Deb, Electrochromic mechanism in a-WO3-y thin films, Appl. Phys. Letters, Vol. 74, pp. 242-244 (1999).
[38] Z. A. E. P. Vroon and C. I. M. A. Spee, Sol-gel coating on large area glass sheets for electrochromic device, Journal of Non-Crystalline Solids, Vol. 218, pp. 189-195 (1997).
[39] K. D. Lee, Preparation and electrochromic properties of WO3 coating deposited by the sol-gel method, Solar Energy Materials & Solar Cells, Vol. 57, pp. 21-30 (1999).

[40] L. H. M. Krings, W. Talen, Wet chemical preparation and characterization of electrochromic WO3, Solar Energy Materials & Solar Cells, Vol. 54, pp. 27-37 (1998).
[41] A. Cremonesi, D. Bersani, P. P. Lottici, Y. Djaoued, P. V. Ashrit, WO3 thin films by sol-gel forelectrochromic applications, Journal of Non-Crystalline Solids, Vol. 345 & 346, pp. 500-504 (2004).
[42] http://www.kojundo.co.jp/Japanese/Faq/handling/faq01.html
[43] M. Deepa, T. K. Saxena, D. P. Singh, K. N. Sood, S. A. Agnihotry, Spin coated versus dip coated electrochromic tungsten oxide films: Structure, morphology, optical and electrochemical properties, Electrochimica Acta, Vol. 51, pp. 1974-1989 (2006).
[44] E. A. Meulenkamp, Mechanism of WO3 Electrodeposition from Peroxy‐Tungstate Solution, Journal of the Electrochemical Society, Vol. 144, pp. 1664-1671 (1997).
[45] M. Giannouli,G.Leftheriotis, The effect of precursor aging on the morphology and electrochromic performance of electrodeposited tungsten oxide films, Solar Energy Materials & Solar Cells, Vol. 95, pp. 1932-1939 (2011).
[46] A.K. Srivastava, M. Deepa, S. Singh, R. Kishore, S.A. Agnihotry, Microstructural and electrochromic characteristics of electrodeposited and annealed WO3 films, Solid State Ionics, Vol. 176, pp. 1161-1168 (2005).
[47] M. Deepa, A.K. Srivastava, S.N. Sharma, Govind, S.M. Shivaprasad Microstructural and electrochromic properties of tungsten oxide thin films produced by surfactant mediated electrodeposition, Applied Surface Science, Vol. 254, pp. 2342-2352 (2008).
[48] A. Danine, L. Cojocaru, C. Faure, C. Olivier, T. Toupance, G. Campet, A. Rougier, Room Temperature UV treated WO 3 thin films for electrochromic devices on paper substrate, Electrochimica Acta, Vol.129 , pp.113–119(2014).
[49] A. Bessière, C. Marcel, M. Morcrette, J.M. Tarascon, V. Lucas, B. Viana, and N. Baffier, Flexible electrochromic reflectance device based on tungsten oxide for infrared emissivity control, Journal of Applied Physics, Vol.91, pp.1589-1594(2002).
[50] C.M. White, D.T. Gillaspie, E. Whitney, S.H. Lee, A.C. Dillon, Flexible electrochromic devices based on crystalline WO3 nanostructures produced with hot-wire chemical vapor deposition, Thin Solid Films, Vol.517, pp.3596–3599(2009).
[51] M. Wang, G. Fang, L. Yuan, H. Huang,Z. Sun, N. Liu, S. Xia and X. Zhao, High optical switching speed and flexible electrochromic display based on WO3 nanoparticles with ZnO nanorod arrays’ supported electrode, Nanotechnology, Vol. 20, 185304(6pp) (2009).
[52] L. Liang, J. Zhang, Y. Zhou, J. Xie, X. Zhang, M. Guan, B. Pan & Y. Xie, High-performance flexible electrochromic device based on facile semiconductor-to-metal transition realized by WO3．2H2O ultrathin nanosheets, Scientific reports, doi: 10.1038(2013).
[53] 何明橋，材料強度破壞學，劉松柏，台北縣，2000年3月。
[54] 陳冠廷，ITO薄膜鍍製於可撓性基板的彎曲疲勞壽命分析，國立成功大學，機械工程系碩士，2012年7月。

[55] 武紅幸，以濺鍍技術製備ITO透明導電薄膜成長在不同基材其應力行為及基材效應對其光學性質之研究，國立交通大學，材料科學與工程學系碩士，2011年7月。
[56] W. Chenga, E. Baudrina, B. Dunna and J. I. Zink, Synthesis and electrochromic properties of mesoporous tungsten oxide, The Royal Society of Chemistry, No. 3, pp. 26–29(2001).
[57] 王輝清、陳俊維、陳榮陞，多層薄膜應力分析及探討，中國機械工程學會第二十四屆全國學術研討會論文，2007年11月。