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arXiv · 1003.5842

Formation of Epitaxial Graphene on SiC(0001) using Vacuum or Argon Environments

Luxmi·N. Srivastava·R. M. Feenstra·P. J. Fisher
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Abstract

The formation of graphene on the (0001) surface of SiC (the Si-face) is studied by atomic force microscopy, low-energy electron microscopy, and scanning tunneling microscopy/spectroscopy. The graphene forms due to preferential sublimation of Si from the surface at high temperature, and the formation has been studied in both high-vacuum and 1-atm-argon environments. In vacuum, a few monolayers of graphene forms at temperatures around 1400 C, whereas in argon a temperature of about 1600 C is required in order to obtain a single graphene monolayer. In both cases considerable step motion on the surface is observed, with the resulting formation of step bunches separated laterally by >10 microns. Between the step bunches, layer-by-layer growth of the graphene is found. The presence of a disordered, secondary graphitic phase on the surface of the graphene is also identified.

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Luxmi, N. Srivastava, R. M. Feenstra, P. J. Fisher. 2010-03-30. Formation of Epitaxial Graphene on SiC(0001) using Vacuum or Argon Environments. https://doi.org/10.1116/1.3420393

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