石墨烯 (Graphene) 為單層碳原子的二維 (2D) 材料，具有許多優異的特性，如：高光穿透性、機械可撓性、低阻抗及高遷移率，理論上可與任何具有中等載子密度的半導體產生蕭基接面 (Schottky junction)，在光伏元件的應用上已被視為具相當發展潛力的材料。
本論文嘗試製作石墨烯/矽以及石墨烯/砷化鎵蕭基接面太陽能電池。首先探討何種摻雜濃度的矽基板能最佳化矽/石墨烯蕭基接面太陽能電池的效率，實驗發現以摻雜濃度為10^15 cm^-3的矽基板所製備的電池具有最高效率，達1.55%。其次，本實驗以分子束磊晶(MBE)成長砷化鎵(GaAs)薄膜於高摻雜濃度的GaAs基板上，觀察磊晶薄膜之成長時間以及摻雜濃度對元件效率的影響，最終製備的電池最高效率為0.143%。

Graphene, as a two-dimensional carbon material, has shown superior material properties including high optical transmittance, excellent mechanical flexibility, low resistivity, and high carrier mobility. Theoretically, a Schottky junction can be formed by depositing graphene onto the surface of a moderately n-doped semiconductor. Thus, graphene is expected to have great potential in the field of photovoltaics.
In this study, the feasibility of graphene/Si and graphene/GaAs Schottky junction solar cells was investigated. For the former, graphene was transferred directly onto n-type Si substrates of different doping concentrations. We found that for the Si substrate doped in the order of 10^15 cm^-3, the graphene/Si junction exhibited a well rectified behavior, and the resulting solar cell showed a maximum efficiency of 1.55 %. For the type of graphene/GaAs junction solar cells, graphene was transferred directly onto the GaAs films grown by MBE on highly n-doped GaAs substrates. The effects of GaAs doping concentration and growth time on the performance of the cells were investigated. These junction solar cells showed a maximum efficiency of 0.143%.

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