Improved growth, ordering, and characterization of sidewall epitaxial graphene nanoribbons

Abstract

One material that has drawn much attention as a viable supplementary material to silicon is graphene, an atom-thick sheet of carbon in a hexagonal lattice. Graphene has many desirable qualities, including massless Dirac fermion charge carriers and an intrinsically two-dimensional structure. However, graphene is a semi-metal; it lacks a bandgap. Therefore, the purpose of this work is to explore a structured graphene geometry that is shown to produce a new form of semiconducting graphene seamlessly connected to metallic graphene nanoribbons. Nanoribbons are patterned and grown on silicon carbide with a combined top-down/bottom-up fabrication method that is compatible with current lithographic technology. Surface characterization measurements, including angle-resolved photoemission spectroscopy (ARPES), low-energy electron microscopy (LEEM), and photoemission electron microscopy (PEEM), are used to characterize ribbon samples and verify semiconducting and metallic properties of the structured graphene.