本研究是在對高分子太陽能電池中的主動層做糙化處理，糙化過的主動層可提升對光捕捉的能力也增加主動層與陰極之間的接觸面積，進而提升短路電流密度(Jsc)，使光電轉換效率(PCE)提升，糙化方法主要是利用軟微影技術，共有兩種母模，一為光柵結構，另一為糙化結構，經過實驗得知，含有光柵結構可使電流密度從8.95提升至9.68 mA/cm2，填充因子(F.F.)亦從0.489提升至0.591，開路電壓(Voc)維持為0.59V，因此效率從2.58提升至3.375%，含有糙化結構則可使電流密度從8.61提升至9.61 mA/cm2，填充因子(F.F.)從0.452提升至0.58，開路電壓(Voc)維持為0.59V，因此效率從2.3提升至3.29%，後續討論提升效率的主因為何，並找出粗糙度(Ra)與效率之間的關係，發現當粗糙度較低時(<7.47nm)可使短路電流密度及填充因子上升，達到提升光電轉換效率的目的。

The purpose of this study is to rough the active layer of polymer solar cell. The rough active layer not only enhance the light trapping but also add the contact area between active layer and the cathode. It will increase the short-circuit current density (Jsc) and then improve the Power Conversion Efficiency (PCE).
Soft Lithography is the main way of rough process. There are two kinds of mold. One is grating Structure. The other is rough structure. The result of experiment shows that Active layer with grating structure will lead the current density up to the 9.68 from 8.95. The fill factor will also up to 0.591 from 0.489. As to the open circuit voltage, it will maintain 0.59V. In summary, the efficiency will up to 3.375% from 2.58%. The result of experiment shows that Active layer with rough structure will lead the current density up to the 9.61 from 8.61. The fill factor will also up to 0.58 from 0.452. As to the open circuit voltage, it will maintain 0.59V. In summary, the efficiency will up to 3.29% from 2.3%.
Furthermore, we discussed the main reason why the efficiency would be higher and found the relation between Ra and the efficiency. When the surface roughness is less than 7.47nm, the short-circuit current density and the fill factor will increase. And then, to reach the purpose, that is, increase the Power Conversion Efficiency.

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