中文摘要

有機高分子太陽能電池具有可撓曲、輕薄、快速製作、大面積製作及常溫製程等優點。在本篇論文中我們藉由改變不同退火溫度的處理方式與改變不同的陰極金屬來找到一個最適合作製作有機太陽能電池的製程條件。
有機太陽能電池之主動層在利用退火處理後，能獲得了較佳的結晶性與有秩序性的分子排列，使得P3HT分子能具有較長的有效共軛長度與較好的載子移動率，填充因子能由0.379%改善至0.439% ; 退火處理亦使得主動層具有較大的有效吸光面積與吸收度，短路電流密度能由3.766 mA/cm2增加到5.661mA/cm2，最大輸出電流能有兩倍的提升，光電轉換效率能由0.568%改善至1.16%。使用較低功函數的鈣金屬電極，開路電壓能明顯地由0.424V改善到0.564V，光電轉換效率更再提升到了1.722%。

Polymer-based solar cells have the advantages of being flexible, low-cost, ease of fabrication and suitable for large-area production which offer them the potential to become the future renewable energy sources. In this thesis, we aim to find optimum fabrication conditions for P3HT : PCBM bulk heterojunction solar cells by investigating the effect of cathode materials and device annealing temperatures to the power conversion efficiencies of device. The results show that higher crystallinity, and light absorption, together with the increased effective conjugation length of P3HT after thermal annealing are the main reasons for greatly improved device efficiencies. The fill factor increased from 0.38 to 0.44 and the short-circuit current density increased from 3.77 mA/cm2 to 5.66 mA/cm2, which result in an approximately two-fold enhancement in device power conversion efficiencies( from 0.57% for non-anneal device to 1.16 % for annealed device ). When the aluminum cathode was replaced by a low work function metal, such as calcium, the Voc was increased form 0.42 V to 0.56 V and power conversion efficiency of device was further increased to 1.722 %.

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