Graphene with atomically smooth and configuration-specific edges plays the key role in the performance of graphene-based electronic devices. Remote hydrogen plasma etching of graphene has been proven to be an effective way to create smooth edges with a specific zigzag configuration. However, the etching process is still poorly understood. In this study, with the aid of a custom-made plasma-enhanced hydrogen etching (PEHE) system, a detailed graphene etching process by remote hydrogen plasma is presented. Specifically, we find that hydrogen plasma etching of graphene shows strong thickness and temperature dependence. The etching process of single-layer graphene is isotropic. This is opposite to the anisotropic etching effect observed for bilayer and thicker graphene with an obvious dependence on temperature. On the basis of these observations, a geometrical model was built to illustrate the configuration evolution of graphene edges during etching, which reveals the origin of the anisotropic etching effect. By further utilizing this model, armchair graphene edges were also prepared in a controlled manner for the first time. These investigations offer a better understanding of the etching process for graphene, which should facilitate the fabrication of graphene-based electronic devices with controlled edges and the exploration of more interesting properties of graphene.

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具有原子平滑和特定于配置的边缘的石墨烯在基于石墨烯的电子设备的性能中起着关键作用。事实证明，对石墨烯进行远程氢等离子体刻蚀是一种产生具有特定之字形配置的平滑边缘的有效方法。然而，蚀刻工艺仍然知之甚少。在这项研究中，借助于定制的等离子体增强氢蚀刻（PEHE）系统，提出了通过远程氢等离子体进行的详细石墨烯蚀刻工艺。具体而言，我们发现石墨烯的氢等离子体蚀刻显示出很强的厚度和温度依赖性。单层石墨烯的蚀刻过程是各向同性的。这与观察到的双层和较厚石墨烯的各向异性刻蚀效应相反，后者明显地依赖于温度。根据这些观察，建立了一个几何模型来说明在蚀刻过程中石墨烯边缘的构型演变，这揭示了各向异性蚀刻效应的起源。通过进一步利用该模型，还首次以受控方式制备了扶手椅石墨烯边缘。这些研究为石墨烯的蚀刻工艺提供了更好的理解，这将有助于制造具有受控边缘的基于石墨烯的电子设备，并促进人们对石墨烯更有趣的特性的探索。

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