  The materials science of graphene grown epitaxially on the hexagonal basal
planes of SiC crystals is reviewed. We show that the growth of epitaxial
graphene on Si-terminated SiC(0001) is much different than growth on the
C-terminated SiC(000 -1) surface, and discuss the physical structure of these
graphenes. The unique electronic structure and transport properties of each
type of epitaxial graphene is described, as well as progress toward the
development of epitaxial graphene devices. This materials system is rich in
subtleties, and graphene grown on the two polar faces differs in important
ways, but all of the salient features of ideal graphene are found in these
epitaxial graphenes, and wafer-scale fabrication of multi-GHz devices already
has been achieved.
