石墨烯奈米帶獨特的性質突破了石墨烯零帶隙的限制，因此被視為未來奈米元件中通道材料的潛力候選者，然而將大面積石墨烯圖案化至小於100nm且高度方向性的石墨烯奈米帶陣列，仍是一個有待解決的問題。

因此在本論文中提出了一個簡單且可大面積製造石墨烯奈米帶陣列的方法，首先在石墨烯基板上旋塗聚甲基丙烯酸甲酯(poly (methyl methacrylate), PMMA)光阻，接著利用Halbach陣列磁鐵在基板上排列高度方向性的鎳奈米線陣列作為蝕刻遮罩，在後續氧氣等離子蝕刻未受遮蔽的石墨烯，接著利用丙酮和超音波震洗將鎳奈米線和PMMA移除，得到高度方向性的石墨烯奈米帶陣列，並以此石墨烯奈米帶實現高靈敏度之光感測器。

實驗規劃各項儀器來檢測石墨烯奈米帶及其光感測器的特性，以掃描式電子顯微鏡(Scanning Electron Microscope, SEM)、穿透式電子顯微鏡(Transmission Electron Microscope, TEM)、原子力顯微鏡(Atomic Force Microscope, AFM)、拉曼光譜儀(Raman)等量測來分析石墨烯奈米帶的品質、表面形貌和側面結構，透過電流-電壓(I-V)量測光感測器的特性。相較於大片石墨烯之光感測器，石墨烯奈米帶光感測器的暗電流有明顯的下降及靈敏度大幅提升，證實此實驗成功打開石墨烯的能隙，未來有望應用在更多領域並有效提高元件特性。

The unique properties of graphene nanoribbons break through the zero-bandgap limit of graphene and are regarded as potential candidates for materials in future nanodevices. However, patterning graphene nanoribbons with the width smaller than 100 nm are still a challenge. Therefore, in this thesis, a simple method for fabricating large-area graphene nanoribbon arrays was proposed. First, poly(methyl methacrylate) (PMMA) photoresist was spin-coated on the graphene. The highly directional nickel nanowire array as an etching mask was arranged on the substrate using a Halbach array magnet, followed by oxygen plasma etching of the unmasked graphene. The nickel nanowires and PMMA were removed by Acetone and a highly directional graphene nanoribbon array was therefore obtained. Additionally, a high-sensitivity photodetector was realized based on the graphene nanoribbon array. Various experiments were carried out to determine the properties of graphene nanoribbons and their photodetectors. Scanning electron microscope (SEM), transmission electron microscope (TEM), atomic force microscope (AFM), and Raman spectrometer were used to analyze the quality, surface morphology and cross-sectional structure of graphene nanoribbons; the characteristics of photodetectors were analyzed by current-voltage (I-V) curves. Compared with the photodetector based on large-area graphene, the dark current of the graphene nanoribbon photodetector was significantly reduced and the sensitivity was greatly improved. These results confirm that we successfully open the bandgap of graphene, and it is expected to effectively improve devices’ characteristics and can be applied in various fields.

Keywords: graphene, graphene nanoribbon, photodetector

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