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The structural properties of the multi-layer graphene/4H-SiC(000-1) system as determined by Surface X-ray Diffraction

J. Hass·R. Feng·J. E. Millan-Otoya·X. Li·M. Sprinkle·P. N. First·C. Berger·W. A. de Heer·E. H. Conrad
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Abstract

We present a structural analysis of the multi-layer graphene-4HSiC(000-1}) system using Surface X-Ray Reflectivity. We show for the first time that graphene films grown on the C-terminated (000-1}) surface have a graphene-substrate bond length that is very short (0.162nm). The measured distance rules out a weak Van der Waals interaction to the substrate and instead indicates a strong bond between the first graphene layer and the bulk as predicted by ab-initio calculations. The measurements also indicate that multi-layer graphene grows in a near turbostratic mode on this surface. This result may explain the lack of a broken graphene symmetry inferred from conduction measurements on this system [C. Berger et al., Science 312, 1191 (2006)].

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J. Hass, R. Feng, J. E. Millan-Otoya, X. Li, M. Sprinkle, P. N. First, C. Berger, W. A. de Heer, E. H. Conrad. 2007-02-23. The structural properties of the multi-layer graphene/4H-SiC(000-1) system as determined by Surface X-ray Diffraction. https://doi.org/10.1103/physrevb.75.214109

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