太陽能在再生能源中有著不可或缺的地位，太陽每天照射到地球的能量足以供應全球的電力需求，而太陽能電池能有效的將太陽光能量轉換為電能，至今已發展出轉換效率高於45%之太陽能電池，然而成本高昂以及製作過程複雜依舊是無法普及市場的主因，因此本研究以p-type有機半導體材料PEDOT:PSS與n-type矽奈米線所製作的混合型太陽能電池能有效降低製作成本，且能通過簡單的旋轉塗佈製程形成p-n異質接面，並探討n-type矽奈米線結構對於元件表現的影響，我們運用奈米球微影術作為遮罩定位奈米線的直徑與間距大小，後結合簡單操作、反應快速的金屬輔助化學蝕刻法得到奈米線陣列結構，在奈米線密度較高的情況下，其光學平均反射率較低，異質接面的面積為影響效率的主要因素，直徑120 nm且為間距180 nm的PEDOT:PSS覆蓋率大幅改善，其短路電流密度提升至33.6 mA/cm^2且光轉換效率可達10.91%，而在奈米線密度較低的陣列結構，其光學反射率因直徑與間距大小改變而差異甚大，直徑420 nm且間距為180 nm的奈米線陣列的短路電流光轉換效率為10.30%，最後本研究探討奈米線形貌改變對於混合太陽能電池之表現比較，藉由提高氫氟酸濃度與過氧化氫濃度的比例而使N(110)蝕刻方向往<100>進而得到傾斜奈米線陣列，後我們將此結構應用於混合太陽能電池，與垂直奈米線陣列結構相比，其效率提升了12%且短路電流密度可達35.24 mA/cm^2、填充因子增加至63.4%，證明傾斜奈米線結構對於混合型太陽能電池元件有更佳的表現。

Due to energy demand increasing rapidly in recent twenty years, solar energy is a promising alternative energy because of being a clean and abundant energy source. Hybrid solar cells combining the advantages of organic and inorganic materials is a cost-effective method to harvest solar energy. In this study, n-type silicon nanowire-based solar cells coated with p-type conductive polymer PEDOT:PSS presents that power conversion efficiency is greatly improved compared with planar silicon-based cells. Large-scale and well-aligned silicon nanowire arrays are successfully fabricated by nanosphere lithography combined with metal-assisted chemical etching. Moreover, the diameter and spacing of silicon nanowires can be controlled by tuning the reactive ion etching time. In addition, we investigate the optical properties of silicon nanowires with various diameters and spacing, revealing that the reflectance is dramatically reduced as diameter increases and spacing decreases. Furthermore, we demonstrate that the orientation of the silicon nanowires is possible to be tuned by enhancing the ratio of hydrofluoric acid and hydroperoxide concentration up to 17.63 or adding IPA into etchant. Finally, we compare the influences of diameters, spacing and orientation of silicon nanowires on cell performances, indicating that slanted silicon nanowire-based hybrid solar cells have the best performance with power conversion efficiency of 12.23 %, open-circuit voltage of 0.548 V, short-circuit current density of 35.24 mA/cm^2, and fill factor of 63.4%.

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