本研究透過在溶膠凝膠ZnO中摻雜硝酸鋁，使之成為Al/Zn之原子比為0.5 at.%、1 at.%、1.5 at.%及2at.%的溶膠凝膠鋁摻雜氧化鋅(Aluminum-doped Zinc Oxide, AZO)，並將其作為陰極緩衝層應用在反置式有機太陽能電池。
我們探討不同摻雜比例及不同鍛燒溫度對薄膜的影響，並透過量測片電阻、穿透度、表面粗糙度及表面型態等等的薄膜特性，期望找出最佳組合並將其作為反置式有機太陽能電池中的陰極緩衝層。此篇論文中的初始元件結構為ITO/AZO(ZnO)/P3HT:PCBM/MoO3/Ag，但研究時發現在AZO薄膜之上加一層ZnO保護層會有更佳的效果，其詳細內容將在論文中探討，而最終的元件結構將變為ITO/AZO/ZnO/P3HT:PCBM/MoO3/Ag。
單層膜之實驗結果發現，AZO(1 at.%)以500鍛燒後會有最好的電性表現，片電阻可從原來ZnO的3.74×108 Ω/sq下降至4.62×106 Ω/sq，以此膜製作之元件其尖刺狀的表面型態會造成與主動層的接觸情況不良，使短路電流和Fill Factor下降，最終使元件PCE有下降之趨勢。
為了解決尖刺狀表面型態的問題，當初構想是以一層薄的ZnO來達到填平保護之效果，但意外發現在此雙層膜的情況下，其各方面的表現有更進一步的提升，片電阻由原來AZO單層膜的4.62×106 Ω/sq下降至4.41×105 Ω/sq，穿透度在可見光波段都保有90%以上。最終製作之元件雖比ZnO標準元件多了一層界面而降低些許Fill Factor，但其短路電流密度由6.2 mA/cm2提升至15.1 mA/cm2，PCE也從2.5%提升至3.93%，電流提升幅度超過143%，PCE提升幅度超過57%。

In this study, we doped aluminum nitrate nonahydrate into sol-gel zinc oxide (ZnO) to make it become Al-doped zinc oxide (AZO). The Al/Zn atomic ratios were set at 0.5 at.%, 1 at.%, 1.5 at.% and 2 at.%. We successfully used this thin film as cathode buffer layer in inverted organic solar cell (IOSCs).
We explore the effect of different doping ratios and different calcination temperatures on the film, and by measuring film properties such as sheet resistance, transparency, surface roughness and surface morphology, expect to find the best combination and take it as cathode buffer layer in inverted organic solar cells. The initial device structure in this paper is ITO/AZO(ZnO)/P3HT:PCBM/MoO3/Ag. However, it was found that adding a thin ZnO protective layer on the AZO film would have better results, so the final structure of the device will be ITO/AZO/ZnO/P3HT:PCBM/MoO3/Ag.
The results of the AZO(1 at.%) single-layer film experiment show that the best electrical performance is obtained after calcined at 500°C. The sheet resistance can be reduced from 3.74×108 Ω/sq of the original ZnO to 4.62×106 Ω/sq. But, the component with this film will cause poor contact condition with the active layer because of the spike-like surface morphology, the short-circuit current and the fill factor will decrease, and eventually the PCE of the element will have a tendency to decrease.
In order to solve the problem of spike-like surface morphology, the original concept was using a thin ZnO layer as protective layer to cover the spike-like structure. However, it was unexpectedly found that in this case of the double-layer film, its performance in various aspects has been further improved. The sheet resistance decreased from 4.62×106 Ω/sq to 4.41×105 Ω/sq, and the transparency was also maintained at more than 90% in the visible light band. Although the final fabricated device has one more interface and reduced the fill factor slightly compared to the ZnO standard device, the short-circuit current increased from 6.2 mA/cm2 to 15.1 mA/cm2, the PCE also increased from 2.5% to 3.93%, short-circuit current increase exceeded 143%. PCE improved by more than 57%.

中文審定書 i
英文審定書 ii
致謝 iii
中文摘要 v
Abstract vi
目錄 viii
圖目錄 xi
表目錄 xiv
第一章 序論 1
1-1再生能源 1
1-2太陽能電池種類與介紹 2
1-3有機太陽能電池結構發展 4
1-3-1單層結構有機太陽能電池 4
1-3-2雙層異質接面有機太陽能電池 5
1-3-3混合層異質接面有機太陽能電池 6
1-3-4加入電極緩衝層之混合層異質接面有機太陽能電池 7
第二章 有機太陽能電池基礎理論 8
2-1 能量及電荷轉移機制 8
2-2 有機太陽能電池工作原理 9
2-2-1吸收入射光產生激子(Light Absorption) 10
2-2-2激子漂移(Exciton Diffusion) 11
2-2-3激子分離(Exciton Dissociation) 12
2-2-4電荷收集(Charge Collection) 13
2-3 太陽能電池等效電路 15
2-4有機太陽能電池特性參數分析 17
2-4-1 短路電流(Short-Circuit Current, ISC) 18
2-4-2 開路電壓(Open-Circuit Voltage, VOC) 18
2-4-3 填充因子(Fill Factor, F.F.) 18
2-4-4 功率轉換效率(Power Conversion Efficiency, PCE) 19
第三章 實驗 20
3-1 實驗動機及架構 20
3-2 實驗藥品 22
3-3 製程設備 25
3-3-1 超音波清洗機(Ultrasonic Cleaning) 25
3-3-2 電磁加熱攪拌器(Hot Plate/Magnetic Stirrer) 26
3-3-3 旋轉塗佈機(Spin Coater) 26
3-3-4 紫外線曝光機(UV Exposure) 27
3-3-5 手套箱(Glove Box) 27
3-3-6 蒸鍍機(Evaporator) 28
3-4 量測分析設備 29
3-4-1 四點探針(Four-point Probe) 29
3-4-2 表面輪廓儀(Surface Profiler/α-step) 30
3-4-3 原子力掃描探針顯微鏡(Atomic Force Microscopy) 31
3-4-4 太陽光譜模擬測量系統(Solar Simulator) 34
3-4-5光電子光譜分析儀(Photo-Electron Spectroscopy in Air) 35
3-4-6 紫外光-可見光光譜儀(UV-Visible Spectrometer) 36
3-4-7 X光繞射儀（X-ray Diffractometer, XRD） 37
3-5 藥品配製 38
3-5-1 氧化鋅(ZnO)溶膠凝膠配製 38
3-5-2 鋁摻雜氧化鋅(AZO)溶膠凝膠配製 38
3-5-3 主動層材料(P3HT/PCBM)配製 38
3-6 實驗步驟 39
3-6-1 ITO基板圖形化 39
3-6-2 圖形化後ITO基板及康寧玻璃基板清洗 41
3-6-3 反置式有機太陽能電池基本元件製程 41
第四章 結果與討論 43
4-1 AZO單層膜 43
4-1-1 不同濃度對薄膜片電阻之影響 43
4-1-2 不同鍛燒溫度對AZO(1 at.%)薄膜片電阻之影響 45
4-1-3 薄膜穿透度之量測分析 46
4-1-4薄膜表面型態之量測分析 47
4-1-5 元件製作 49
4-2 AZO搭配ZnO之雙層膜 51
4-2-1不同濃度AZO薄膜搭配ZnO後對片電阻之影響 51
4-2-2薄膜穿透度之量測分析 53
4-2-3薄膜表面型態之量測分析 54
4-2-4元件製作 56
第五章 總結 59
參考文獻 60

[1] Kearns, D., & Calvin, M. (1958). Photovoltaic effect and photoconductivity in laminated organic systems. The Journal of chemical physics, 29(4), 950-951.
[2] Tang, C. W. (1986). Two‐layer organic photovoltaic cell. Applied Physics Letters, 48(2), 183-185.
[3] Sariciftci, N. S., Smilowitz, L., Heeger, A. J., & Wudl, F. (1992). Photoinduced electron transfer from a conducting polymer to buckminsterfullerene. Science, 1474-1476.
[4] Yu, G., Gao, J., Hummelen, J. C., Wudl, F., & Heeger, A. J. (1995). Polymer photovoltiac cells: Enhanced efficiencies via a network of internal donor-acceptor heterojunctions. Science, 270(5243), 1789-1791.
[5] Green, M. A. (1982). Solar cells: operating principles, technology, and system applications.
[6] 莊嘉深. (1997). 太陽能工程-太陽電池篇, 全華圖書.
[7] Brabec, C. J., Cravino, A., Meissner, D., Sariciftci, N. S., Rispens, M. T., Sanchez, L., ... & Fromherz, T. (2002). The influence of materials work function on the open circuit voltage of plastic solar cells. Thin solid films, 403, 368-372.
[8] Sun, Y., Seo, J. H., Takacs, C. J., Seifter, J., & Heeger, A. J. (2011). Inverted polymer solar cells integrated with a low‐temperature‐annealed sol‐gel‐derived ZnO film as an electron transport layer. Advanced Materials, 23(14), 1679-1683.
[9] Li, D., Chen, Y., Du, P., Zhao, Z., Zhao, H., Ma, Y., & Sun, Z. (2015). An annealing-free anatase TiO 2 nanocrystal film as an electron collection layer in organic solar cells. RSC Advances, 5(108), 88973-88978.

[10] Oo, T. Z., Chandra, R. D., Yantara, N., Prabhakar, R. R., Wong, L. H., Mathews, N., & Mhaisalkar, S. G. (2012). Zinc Tin Oxide (ZTO) electron transporting buffer layer in inverted organic solar cell. Organic Electronics, 13(5), 870-874.
[11] Cheun, H., Fuentes-Hernandez, C., Zhou, Y., Potscavage Jr, W. J., Kim, S. J., Shim, J., ... & Kippelen, B. (2010). Electrical and optical properties of ZnO processed by atomic layer deposition in inverted polymer solar cells. The Journal of Physical Chemistry C, 114(48), 20713-20718.
[12] Cheng, Y., Yang, Q. D., Xiao, J., Xue, Q., Li, H. W., Guan, Z., ... & Tsang, S. W. (2015). Decomposition of organometal halide perovskite films on zinc oxide nanoparticles. ACS applied materials & interfaces, 7(36), 19986-19993.
[13] Li, P., Wang, G., Cai, L., Ding, B., Zhou, D., Hu, Y., ... & Alameh, K. (2014). High-efficiency inverted polymer solar cells controlled by the thickness of polyethylenimine ethoxylated (PEIE) interfacial layers. Physical Chemistry Chemical Physics, 16(43), 23792-23799.
[14] Yuan, L., Zhao, Y., Zhang, J., Zhang, Y., Zhu, L., Lu, K., ... & Wei, Z. (2015). Oligomeric Donor Material for High‐Efficiency Organic Solar Cells: Breaking Down a Polymer. Advanced Materials, 27(28), 4229-4233.
[15] Kuwabara, T., Nakamoto, M., Kawahara, Y., Yamaguchi, T., & Takahashi, K. (2009). Characterization of ZnS-layer-inserted bulk-heterojunction organic solar cells by ac impedance spectroscopy. Journal of Applied Physics, 105(12), 124513.
[16] Zhu, J. J., Fan, G. Q., Wei, H. X., Li, Y. Q., Lee, S. T., & Tang, J. X. (2012). Solution-processed inverted polymer solar cells using chemical bath deposited CdS films as electron collecting layer. CrystEngComm, 14(23), 8090-8096.


[17] Li, G., Chu, C. W., Shrotriya, V., Huang, J., & Yang, Y. (2006). Efficient inverted polymer solar cells. Applied Physics Letters, 88(25), 253503.
[18] Yip, H. L., & Jen, A. K. Y. (2012). Recent advances in solution-processed interfacial materials for efficient and stable polymer solar cells. Energy & Environmental Science, 5(3), 5994-6011.
[19] Yu, X., Yu, X., Zhang, J., & Pan, H. (2015). Gradient Al-doped ZnO multi-buffer layers: effect on the photovoltaic properties of organic solar cells. Materials Letters, 161, 624-627.
[20] Tsay, C. Y., Wu, C. W., Lei, C. M., Chen, F. S., & Lin, C. K. (2010). Microstructural and optical properties of Ga-doped ZnO semiconductor thin films prepared by sol–gel process. Thin Solid Films, 519(5), 1516-1520.
[21] Caglar, M., Caglar, Y., & Ilican, S. (2007). Electrical and optical properties of undoped and In‐doped ZnO thin films. physica status solidi (c), 4(3), 1337-1340.
[22] Kyaw, A. K. K., Sun, X. W., Jiang, C. Y., Lo, G. Q., Zhao, D. W., & Kwong, D. L. (2008). An inverted organic solar cell employing a sol-gel derived ZnO electron selective layer and thermal evaporated MoO 3 hole selective layer. Applied Physics Letters, 93(22), 221107.
[23] Hong, R. J., Jiang, X., Sittinger, V., Szyszka, B., Höing, T., Bräuer, G., ... & Frischat, G. H. (2002). Uniformity in large area ZnO: Al films prepared by reactive midfrequency magnetron sputtering. Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films, 20(3), 900-905.
[24] Wu, K. Y., Wang, C. C., & Chen, D. H. (2007). Preparation and conductivity enhancement of Al-doped zinc oxide thin films containing trace Ag nanoparticles by the sol–gel process. Nanotechnology, 18(30), 305604.