聚-3己烷塞吩(Poly (3-hexylthiophene), P3HT)混合富勒烯衍生物([6,6]-Phenyl-C61 butyric acid methyl ester, PCBM)之表面型態於影響有機異質接面太陽能電池之效能中扮演很重要的角色。於本論文中，我們探討聚-3己烷塞吩/富勒烯衍生物之濃度影響元件特性。首先對於不同濃度(1wt% ~ 5wt%)對主動層厚度之影響進行研究，可得最佳主動層厚度約為200nm，濃度須介於3wt%至5wt%。更進一步分別對3wt%、4wt%及5wt%於不同熱退火處理之元件進行探討。可得最佳製備條件為4wt%經130oC熱處理，其元件特性之短路電流為11.19 mA/cm2、開路電壓為0.6V、理想因子0.52%，效率可達3.6%。最後，藉由紫外光-可見光吸收光譜，掃描式原子力顯微鏡，X光繞射光譜儀及空間電荷限制電流法推算電子電洞移動速率方式探討濃度對元件特性之影響。

The morphology reveals important role played for photovoltaic properties of bulk heterojunction based on Poly (3-hexylthiophene) (P3HT): [6,6]-Phenyl-C61 butyric acid methyl ester (PCBM). In this study, we investigated the effected of the P3HT:PCBM concentration on the performance of solar cells. At first, we investigate that effect of various concentrations (1wt% ~ 5wt%) on thickness of the active layers. We can obtain that optimal thickness is about 200nm, and the concentrations need to aim at the range from 3wt% to 5wt%. Moreover, the effect of various concentrations (3, 4 and 5wt%) on various annealing temperatures are investigated. The optimal performance is 4wt% concentration annealed at 130 oC, which short-circuit current (JSC) is 11.19 mA/cm2, open-circuit voltage (VOC) is 0.6V, fill factor (FF) is 0.52% , and power conversion efficiency (PCE) is 3.6%. Moreover, the absorption spectrum, photoluminescence spectrum (PL), phase image, X-ray diffraction (XRD), and estimation of hole mobility and electron mobility from spec charge limited current is used to demonstrate the concentration effect on device performance.

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