本論文將自組裝分子薄膜以旋轉塗佈法修飾於有機異質結（P3HT:PCBM）太陽能電池電子傳導層(氧化鋅)上與下界面處，於電子傳導層與主動層處為上界面修飾；於陰極和電子傳導層處為下界面修飾，同時修飾上與下界面於一元件時稱之為雙層修飾。其中，上層修飾以3-氨基丙基三乙氧基矽烷（NH2-SAM）作為自組裝分子薄膜的選擇，NH2-SAM帶推電子基可降低主動層與氧化鋅間的電子注入能障使電池元件效率提升；另一方面，下層修飾選擇兩偶極矩方向相反之苯甲酸衍生物，下層修飾後因造成基板表面能變化，可改善氧化鋅薄膜垂直電阻和氧缺陷含量，使電池內串聯電阻降低並提升元件效率，另發現於下層修飾中，分子偶極矩方向對於元件效率並無直接影響。在雙界面修飾元件時，上與下界面提供的不同修飾性質可疊加，進一步提升元件效率，並以兩相反偶極矩官能基-NH2和-CF3之組合有最佳元件效率，相較標準片元件效率提升約21%。

This study reports the incorporation of self-assembled monolayers (SAMs) into organic photovoltaic devices to investigate the influence of single- and dual-SAM modification approaches, the combined effect, on power conversion efficiency. For this purpose, SAMs of functional benzoic acid groups (BA-SAMs) and silane with donating group (NH2-silane) were employed to modify the surface of ITO (bottom modification) and ZnO layer (top modification) in the organic photovoltaic devices. Top modification created an interface dipole providing superior charge injection between the layers, and bottom modification afforded better charge transport through the ZnO and SAM layer with ignorable of dipole direction. The results showed improvement in device performance for single modification, and most importantly the combination of each effect in dual modification devices brought out further efficiency enhancement. A new dipole behavior was observed at SAM/ZnO interface which contradicts the usual trend of efficiency changing with dipole moment direction. The device with the CF3-SAM demonstrated better performance, suggesting the intuitively unfavorable dipole group provides a better physical contact to ZnO that resulted in primary efficiency improvement.

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