Initial stages of the graphite-SiC(0001) interface formation studied by   photoelectron spectroscopy
  Graphitization of the 6H-SiC(0001) surface as a function of annealing temperature has been studied by ARPES, high resolution XPS, and LEED. For the initial stage of graphitization - the 6root3 reconstructed surface - we observe sigma-bands characteristic of graphitic sp2-bonded carbon. The pi-bands are modified by the interaction with the substrate. C1s core level spectra indicate that this layer consists of two inequivalent types of carbon atoms. The next layer of graphite (graphene) formed on top of the 6root3 surface at TA=1250-1300 degree C has an unperturbed electronic structure. The annealing at higher temperatures results in the formation of a multilayer graphite film. It is shown that the atomic arrangement of the interface between graphite and the SiC(0001) surface is practically identical to that of the 6root3 reconstructed layer. 
K.V. Emtsev, Th. Seyller, F. Speck, L. Ley, P. Stojanov, J.D. Riley,   R.G.C. Leckey