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)].
Cite
@article{arxiv.cond-mat/0702540,
title = {The structural properties of the multi-layer graphene/4H-SiC(000-1) system as determined by Surface X-ray Diffraction},
author = {J. Hass and R. Feng and J. E. Millan-Otoya and X. Li and M. Sprinkle and P. N. First and C. Berger and W. A. de Heer and E. H. Conrad},
journal= {arXiv preprint arXiv:cond-mat/0702540},
year = {2009}
}