能源短缺是本世紀眾所矚目且極待解決的重要議題之一，目前世界各國正積極尋找各種再生能源來取代傳統石化燃料。有機太陽能電池有著製程簡單、成本低廉與可撓性並可進行捲軸式大面積製造等優點，近年來備受大家的期待與矚目。以往有機太陽能電池製程多以旋轉塗佈為主，但無法有效的應用在大面積太陽電池上，因此本研究使用刮刀塗佈來製作大面積有機太陽能電池，不僅可以提高溶液的使用率，更重要的是未來可進一步發展至捲軸式連續製程。
本研究的元件結構為ITO/PEDOT:PSS/blend/Ca/Ag，除了上下電極以外其餘皆為刮刀塗佈的全溶液製程。然而大面積刮刀塗佈的均勻性會受各種因素所影響，例如塗液之流變性及表面張力、操作時之定速以及塗料揮發的速率等等。在本文裡我們討論不同加熱方式，並且選擇沸點較低的CB取代DCB當作主動層溶劑，來解決濕膜因內聚而導致膜厚不均的現象。為了發展串聯式大面積有機太陽能電池，本論文研究在主動區中相同長度下改變不同寬度的太陽電池特性，寬度的選擇為6mm、9mm、12mm和15mm。隨著元件寬度變大，串聯電阻的影響也就越顯著，然而大面積太陽能電池的aperture ratio卻提高，因此我們依實驗的結果並考慮aperture ratio的影響，研究結果顯示當主動區寬度為9mm時，元件的整體效率較為理想，並將此結果與本實驗室先前膜擬大面積太陽能電池的結果進行驗證，相信對於未來進行串聯式大面積太陽能電池是一很好的參考依據。

Energy shortage has become one of the important issues to be resolved. People are eagerly looking for alternative energy sources to replace traditional fossil fuels. Organic solar cells have attracted much attention due to their unique properties such as low-cost, simple fabrication process and flexibility. In addition, it can be combined with roll-to-roll process to fabricate large-area organic solar cell. Most of the organic solar cells are fabricated using spin-coating technique; however, this technique is not applicable for large-area device fabrication. Therefore, we develop blade-coating process to fabricate large-area organic solar cells, not only enhancing the efficiency of material usage but also developing toward roll-to-roll process in the future.
In this work, the hole transport layer and active layer are deposited by blade-coating method. The active layer was a bulk heterojunction (BHJ) consisting of P3HT and PCBM. However, the uniformity of large-area blade-coating will be affected by several factors such as the flow variability, surface tension of the solution and the velocity of blading. We discuss the different heating methods and use low boiling point CB to replace DCB as the solvent of active layer. To develop the serial connection of large-area devices, the scaling effect of the fabricated devices is studied by varying the widths of active area while keeping lengths the same. As a result, with increasing the width of active area, the impact of series resistance is more significant but the aperture ratio is increased. Therefore, an optimal width of the active area could be obtained, showing a good agreement with the simulated results of organic large-area solar cell. Therefore, we expect the series of large-area solar cells could be a good reference for the future.

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