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The interest in graphene stems from its unique band structure that photoemission spectroscopy can directly probe. However, the preparation method can significantly alter graphene's pristine atomic structure and in turn the photoemission spectroscopy spectra. After a short review of the observed band structure for graphene prepared by various methods, we focus on graphene grown on silicon carbide. The semiconducting single crystalline hexagonal SiC provides a substrate of various dopings, where bulk bands do not interfere with that of graphene. Large sheets of high structural quality flat graphene grow on SiC, which allows the exact same material to be used for fundamental studies and as a platform for scalable electronics. Moreover, a new graphene allotrope (multilayer epitaxial graphene) was discovered to grow on the 4H-SiC C-face by the confinement controlled sublimation method. We will focus on the electronic structure of this new graphene allotrope and its connection to its atomic structure.

Graphene nanoribbons are fundamental components to the development of graphene nanoelectronics. At the nanoscale, electronic confinement effects and electronic edge states become essential to the properties of graphene. These effects depend critically on the ribbon width and the nature of the ribbon edge, the control of which at the atomic scale is a major challenge. Graphene nanoribbons have been largely studied theoretically, experimentally and with the perspective of electronic applications. We review the basic properties of graphene nanoribbons and recent progress in fabrication processes, focusing on the question of the electronic gap. We examine top–down and bottom–up approaches to fabricate graphene nanoribbons by lithographic, catalytic cutting, chemical assembly and epitaxial growth methods and compare their electronic characteristics. [ABSTRACT FROM AUTHOR]

We review the progress towards developing epitaxial graphene as a material for carbon electronics. In particular, we discuss improvements in epitaxial graphene growth, interface control and the understanding of multilayer epitaxial graphene's (MEG's) electronic properties. Although graphene grown on both polar faces of SiC will be discussed, our discussions will focus on graphene grown on the (0\,0\,0\,\bar{1}) C-face of SiC. The unique properties of C-face MEG have become apparent. These films behave electronically like a stack of nearly independent graphene sheets rather than a thin Bernal stacked graphite sample. The origins of multilayer graphene's electronic behaviour are its unique highly ordered stacking of non-Bernal rotated graphene planes. While these rotations do not significantly affect the inter-layer interactions, they do break the stacking symmetry of graphite. It is this broken symmetry that leads to each sheet behaving like isolated graphene planes. [ABSTRACT FROM AUTHOR]