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arXiv · 1308.3111

Weak localization and Raman study of anisotropically etched graphene antidots

Florian Oberhuber·Stefan Blien·Stefanie Heydrich·Fatemeh Yaghobian·Tobias Korn·Christian Schüller·Christoph Strunk·Dieter Weiss·Jonathan Eroms
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Abstract

We study a crystallographic etching process of graphene nanostructures where zigzag edges can be prepared selectively. The process involves heating exfoliated single-layer graphene samples with a predefined pattern of antidot arrays in an argon atmosphere at 820 C, which selectively removes carbon atoms located on armchair sites. Atomic force microscopy and scanning electron microscopy cannot resolve the structure on the atomic scale. However, weak localization and Raman measurements - which both probe intervalley scattering at armchair edges - indicate that zigzag regions are enhanced compared to samples prepared with oxygen based reactive ion etching only.

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Florian Oberhuber, Stefan Blien, Stefanie Heydrich, Fatemeh Yaghobian, Tobias Korn, Christian Schüller, Christoph Strunk, Dieter Weiss, Jonathan Eroms. 2013-10-09. Weak localization and Raman study of anisotropically etched graphene antidots. https://doi.org/10.1063/1.4824025

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