本研究以五環素(pentacene)作為P型有機材料，N,N′-Ditridecylperylene-3,4,9,10-tetracarboxylic diimide (PTCDI-13C)作為N型有機材料，製作出pentacene/PTCDI-13C異質接面結構的有機太陽能電池。藉由改變成長在pentacene的駢苯衍生物(PTCDI-13C)厚度來討論PTCDI-13C結構內分子所受的應力對太陽能電池轉換效率的影響。當PTCDI-13C厚度越薄，所受到的應力越大，晶格排列較為混亂，太陽能電池的轉換效率低；當PTCDI-13D厚度逐漸增加，所受的應力逐漸消逝，晶格排列較為整齊，轉換效率亦隨之增加。嘗試利用時間解析螢光光譜測量PTCDI-13C吸收光子後產生的激子(電子電洞對)生命期，發現不同厚度PTCDI-13C產生出的激子具有不同的生命期長度，以厚度50 nm的PTCDI-13C電子電洞對生命期最長，亦即激子有更大的機會可飄移到P/N接面處進行分離成自由電荷而非複合發光；而太陽能元件的轉換效率中發現，當PTCDI-13C的厚度從10 nm改變成50 nm，元件的光轉換效率可由0.08%提升至0.34%；當PTCDI-13C厚度繼續增加至70 nm時，光轉換效率旋即降至0.16%；實驗結果可看出PTCDI-13C厚度對有機太陽能電池光效率轉換的明顯影響，其中厚度對轉換效率的影響機制將在論文中詳細討論。

The pentacene and N,N′-Ditridecylperylene-3,4,9,10-tetracarboxylic diimide (PTCDI-13C) are used as the acceptor and donor to construct the bi-layer organic solar cell in this research. The various thicknesses of PTCDI-13C films were formed in organic solar cell in order to compare the stress effect that influenced the efficiency of the organic solar cell. The results reveal that the maximum efficiency of the organic solar cell occurred at the condition of 50-nm-thick PTCDI-13C film for the release of the stress and without the aggregation of PTCDI-13C molecules. Moreover, the lifetime of exciton in different PTCDI-13C thicknesses were analyzed by time-resolved photoluminescence. The longest exciton lifetime also appeared at the 50-nm-thick PTCDI-13C film to result in easy drift of these excitons to heterojunction of the PTCDI-13C and pentacene and separations of carriers from these excitons. The power conversion efficiency can improved gradually from 0.08% to 0.34% when the thickness of PTCDI-13C film increases from 10 to 50 nm. However, the power conversion efficiency gradually drops from 0.34% to 0.16% when increasing the PTCDI-13C thickness from 50 to 70 nm. The experimental result shows that the thickness of PTCDI-13C film in bi-layer organic solar cell significantly influenced the efficiency of the organic solar cell.

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