Wide bandgap semiconductor from a hidden 2D incommensurate graphene phase

Abstract

Producing a usable semiconducting form of graphene has plagued the development of graphene electronics for nearly two decades. Now that new preparation methods have become available, graphene's intrinsic properties can be measured and the search for semiconducting graphene has begun to produce results. This is the case of the first graphene "buffer" layer grown on SiC(0001) presented in this work. We show, contrary to assumptions of the last forty years, that the buffer graphene layer is not commensurate with SiC. The new modulated structure we've found resolves a long standing contradiction where ab initio calculations expect a metallic buffer, while experimentally it is found to be a semiconductor. Model calculations using the new incommensurate structure show that the semiconducting $\pi$-band character of the buffer comes from partially hybridized graphene incommensurate boundaries surrounding unperturbed graphene islands.

arXiv comment17 pages, 4 figures, 1 table, 47 references, supplemental material: 15 pages, 4 figures

References in corpus (15)

• Monolayer honeycomb structures of group IV elements and III-V binary compounds
• Electronic structure of epitaxial graphene layers on SiC: effect of the substrate
• Localization of Dirac electrons by Moire patterns in graphene bilayers
• Raman spectroscopy of epitaxial graphene on a SiC substrate
• Raman spectroscopy of graphene and bilayer under biaxial strain: bubbles and balloons
• Ab initio Study of Graphene on SiC
• Large area and structured epitaxial graphene produced by confinement controlled sublimation of silicon carbide
• Origins of anomalous electronic structures of epitaxial graphene on silicon carbide
• Highly-ordered graphene for two dimensional electronics
• The quasi-free-standing nature of graphene on H-saturated SiC(0001)
• How Graphene-like is Epitaxial Graphene? \\Quantum Oscillations and Quantum Hall Effect
• Semiconducting graphene from highly ordered substrate interactions
• Revealing the atomic structure of the buffer layer between SiC(0001) and epitaxial graphene
• Character of electronic states in graphene antidot lattices: Flat bands and spatial localization
• The effect of the buffer layer coupling on the lattice parameter of epitaxial graphene on SiC(0001)

Cited by in corpus (7)

• The structure and evolution of semiconducting buffer graphene grown on SiC(0001)
• Graphene: Free electron scattering within an inverted honeycomb lattice
• Dirac Fermion Cloning, Moir$\acute{\mathbf{e}}$ Flat Bands and Magic Lattice Constants in Epitaxial Monolayer Graphene
• Surfactant-Mediated Epitaxial Growth of Single-Layer Graphene in an Unconventional Orientation on SiC
• Edge states and ballistic transport in zig-zag graphene ribbons: the role of SiC polytypes
• The effects of Moire lattice on the electronic properties of graphene
• Substitutional mechanism for growth of hexagonal boron nitride on epitaxial graphene