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arXiv · 1212.1647

Contribution of the buffer layer to the Raman spectrum of epitaxial graphene on SiC(0001)

F. Fromm·M. H. Oliveira Jr·A. Molina-Sánchez·M. Hundhausen·J. M. J. Lopes·H. Riechert·L. Wirtz·T. Seyller
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Abstract

We report a Raman study of the so-called buffer layer with $(6\sqrt3\times6\sqrt3)R30^{\circ}$ periodicity which forms the intrinsic interface structure between epitaxial graphene and SiC(0001). We show that this interface structure leads to a nonvanishing signal in the Raman spectrum at frequencies in the range of the D- and G-band of graphene and discuss its shape and intensity. Ab-initio phonon calculations reveal that these features can be attributed to the vibrational density of states of the buffer-layer.

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F. Fromm, M. H. Oliveira Jr, A. Molina-Sánchez, M. Hundhausen, J. M. J. Lopes, H. Riechert, L. Wirtz, T. Seyller. 2012-12-07. Contribution of the buffer layer to the Raman spectrum of epitaxial graphene on SiC(0001). https://doi.org/10.1088/1367-2630/15/4/043031

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