本研究在對反置型有機太陽能電池中的電子傳輸層及主動層做微奈米結構，希望藉由微奈米結構增加電子傳輸層或主動層的接觸面積來提升填充因子(F.F)，並藉由光進入微奈米結構使光反射下降，進而提升短路電流密度(Jsc)，使光電轉換效率(PCE)提升。壓印方法主要是利用軟微影技術，依壓印母模結構不同可分為兩部份(1)利用PDMS翻DVD+R光柵結構；(2)利用PDMS翻PUA柱狀結構，比較探討壓印對電子傳輸層或主動層之反射以及效率的影響，光柵結構電子傳輸層效率由2.39%提升至2.65%，柱狀結構電子傳輸層光電轉換效率可提升至3%，主要提升為填充因子從0.5提升至0.573，結果顯示電子傳輸層上製作柱狀結構會比光柵結構好，於主動層上之光柵結構主動層效率也有進一步提升，主要為填充因子從0.5提升至0.59，其次為短路電流密度從9.02提升至9.73 (mA/cm2)，效率從2.4%提升至3.0%，而主動層上製作柱狀結構推論因柱狀深度過深，密度過大，因此反而與溶液塗佈之PEDOT接觸不佳；因而有孔隙，使光電轉換效率下降，比較光柵結構於電子傳輸層及主動層，可以得到光柵結構主動層效率優於光柵結構電子傳輸層效率，結果顯示在於填充因子的提升，推論原因為主動層材料之電洞載子移動率低於電子載子移動率，因此在主動層與電洞傳輸層間製作微奈米結構是較有助於整體元件效率的提升。

The objective of this study is to fabricate nanostructure on electron transport layer and active layer of inverted organic solar cells. By using the technique to add contact area and light absorption, we are able to enhance Fill factor and the power efficiency. There are two parts to fabricate molds in imprinting process：(1) Using PDMS to fabricate DVD+R grating structure. (2) Using PDMS to fabricate column structure. In grating structure on electron transport layer, the value of power efficiency rises from 2.39 to 2.65%. In column structure on electron transport layer, the value of the power efficiency can enhance to 3%, and the value of Fill factor increases from 0.5 to 0.57. This result shows that fabricating the column structure is better than fabricating the grating structure in electron transport layer. Another way to imprint grating structure on active layer can enhance the power efficiency. The value of Fill factor increases from 0.5 to 0.59. The current density rises from 9.02 mA/cm2 to 9.73 mA/cm2. The value of the power efficiency rises from 2.4 to 3.0%. But there are some problems of fabricating the column structure on active layer need to be solved. So the power efficiency is unexpected. Compared with the grating structure on electron transport layer, the power efficiency of grating structure on active layer can be better because the value of Fill factor has increased. We infer that the mobility of electron hole is less than the mobility of electron, and then fabricating nanostructure on active layer can promote Power Conversion Efficiency(PCE).

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