In situ study on the electronic structure of graphene grown on 6H-SiC (0001¯) with synchrotron radiation photoelectron spectroscopy

► We examine the electronic structures of the graphene grown on 6H-SiC (0001¯). ► The LEED results showed the several reconstructions of 6H-SiC and the anisotropic graphene layers. ► The C 1s core levels showed that the interface interaction was weak. ► The existence of Si clusters was confirmed by Si 2p core levels. ► The valence band spectra indicated that both of σ and π bonds existed.