由於砷化鎵基板仍十分昂貴，且太陽能電池需要同時兼顧效率與成本，近年來，核殼結構砷化鎵奈米線不再成長於砷化鎵基板上，而是以鎵自催化方式成長於矽基板上。為了做成太陽能電池元件，核殼結構砷化鎵奈米線必須在基板與上電極間製作一層絕緣層以防止短路，然而砷化鎵奈米線在此方面的製程上仍然找不到一個合宜的解決方式。
PEDOT:PSS是目前最有潛力的有機半導體材料之一，且與砷化鎵及矽皆能形成合適的P-N接面，不須顧慮到短路的問題。本研究即以導電高分子PEDOT:PSS作為P型半導體材料，取代核殼結構太陽能電池中的殼層。我們分別在砷化鎵奈米線與氧化銦錫導電玻璃上旋轉塗佈一層PEDOT:PSS薄膜，再將奈米線與導電玻璃結合，形成砷化鎵/PEDOT:PSS混合型太陽能電池元件，並分別對不同直徑、長度的奈米線及PEDOT:PSS旋轉塗佈速度進行轉換效率的探討。本研究中得到的最高效率為4.58 x 10-3%。

Since the cost of gallium arsenide(GaAs) substrate is expensive, core-shell GaAs nanowires(NWs), which used to be grown on GaAs substrate, had turned to be grown on silicon(Si) substrate via the self-catalyzed mechanism in recent years. In order to make a solar cell device, core-shell GaAs NWs must produce one insulator layer between top electrode and substrate to prevent short-circuiting. However, we still cannot find a decent solution for it.
Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) is currently one of the most promising conducting polymers, which has great formation of p-n junction with both GaAs and Si. This could solve the short-circuiting problem between top electrode and silicon substrate.
In this study, we use PEDOT:PSS as a P-type semiconductor material to replace the shell layer in core-shell structure. PEDOT:PSS thin film were spin coated on GaAs NWs and indium tin oxide conductive glass. Afterwards, the nanowire set were pressed onto the conductive glass to fabricate the GaAs/PEDOT:PSS hybrid solar cell device. We discussed the effect of the nanowire length, diameter and spin coating speed on the optical properties of nanowire devices. The best power conversion efficiency in our work is 4.58 x 10-3%.

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