Abstract
We report a chemically specific x-ray photoelectron diffraction (XPD) investigation using synchrotron radiation of the thermally induced growth of epitaxial graphene on the 6-SiC(0001). The XPD results show that the buffer layer on the SiC(0001) surface is formed by two domain regions rotated by with respect to each other. The experimental data supported by a comprehensive multiple scattering calculation approach indicates the existence of a long-range ripple due the reconstruction, in addition to a local range buckling in the (0001) direction of the two sublattices that form the honeycomb structure of the buffer layer. This displacement supports the existence of an -to- rehybridization in this layer. For the subsequent graphene layer this displacement is absent, which can explain several differences between the electronic structures of graphene and the buffer layer.
- Received 27 June 2012
DOI:https://doi.org/10.1103/PhysRevB.87.081403
©2013 American Physical Society