本研究探討處理後之聚二氧乙基噻吩(PEDOT)薄膜導電度影響，及其作為有機太陽能電池電極的可行性。利用兩個方法對薄膜進行處理，其一為將PEDOT薄膜浸泡於甲醇，透過簡單的處理方式提升薄膜導電度、穿透度以及電荷傳輸能力，其二為利用甲醇蒸氣對PEDOT薄膜進行處理，透過改善製程以更好地應用在有機太陽能元件製程上，並藉由元件電性分析確認此薄膜電極可取代傳統銦錫氧化物(ITO)電極。利用四點探針、霍爾量測系統、吸收光譜儀、拉曼光譜儀、原子力顯微鏡以及化學分析電子光譜儀對PEDOT薄膜進行量測及分析，並進一步了解PEDOT薄膜電極對太陽能元件的電性影響。
本研究亦將PEDOT薄膜應用於有機太陽能元件中，並選用兩種不同主動層材料系統：(1) 聚(3-己烷噻吩)(Poly(3-hexylthiophene),P3HT)摻雜碳六十衍生物([6,6]-phenyl-C61 butyric acid methyl ester,PCBM)，溶劑為CB、(2) P3HT摻雜茚-碳六十的雙加成物(Indene-C60 bisadduct,ICBA)，溶劑為DCB。由薄膜特性分析發現，處理過後的薄膜片電阻由未處理之薄膜為25000 Ω/Sq大幅下降為78.9 Ω/Sq，且處理過後的薄膜仍保有85%的透光度，元件電性分析可知，以甲醇溶液浸泡與甲醇蒸氣進行處理的PEDOT薄膜皆可作為電極使太陽能電池正常運作，且太陽能電池的光電轉換效率非常接近使用傳統ITO電極的電池元件，其中除了元件的短路電流密度(Jsc)未能有效提昇，但開路電壓(Voc)幾乎相同，填充因子FF 則有輕微增加。

In this study, we investigated the treatment methods for improving the conductivity of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) films as the anode of organic solar cells (OSCs) employing polymer–fullerene bulk heterojunction. Two methods were proposed for the treatment of the PEDOT:PSS films; one is by immersing the film in a methanol solution, and the other is by treating the film with methanol vapor. The prepared PEDOT:PSS films were characterized by four-probe technique, absorption and Raman spectroscopy, conductive atomic microscopy, and X-ray photoelectron spectroscopy. The photovoltaic (PV) performance of OSCs using treated PEDOT:PSS anode were compared with that of OSCs using conventional indium tin oxide (ITO) anode. The sheet resistance of the methanol-treated PEDOT:PSS films is only 78.9 Ω/Sq, which decreases by more than 99% compared with that of the initial films (25000 Ω/Sq). The methanol-treated PEDOT:PSS films show high transparency, low sheet resistance, and excellent mechanical properties, which are the desired characteristics of a transparent electrode. Finally, we realized ITO-free polymer–fullerene-based OSCs using PEDOT:PSS as anode, and the PV performance is nearly equal to that of conventional OSCs with ITO anode.

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