Observation of layer by layer graphitization of 4H-SiC, through atomic-EELS at low energy

Graphitization of SiC, is attracting particular research interest since it is a very promising way to produce uniform graphene films over large areas. Graphene is a planar one-atom-thick layer of sp2bonded carbon atoms with remarkable electronic transport properties that make it a potential candidate for future electronic applications. However, graphene presents specific structural and electronic properties depending on the growth substrate and mechanism, which consequently have an impact on its macroscopic electrical behavior. In the case of epitaxial graphene (EG) grown on Si-polarized SiC, a crucial role is played by the presence of a so-called carbon “buffer layer” or “0 layer”. Such layer has been shown to present a certain degree of sp 3 hybridization since it is partially bound to the outmost Si atoms of the SiC (0001) surface [1].