We present electronic structure calculations of few-layer epitaxial graphene nanoribbons on SiC(0001). Trough an atomistic description of the graphene layers and the substrate within the extended Hückel theory and real/momentum space projections we argue that the role of the heterostructure’s interface becomes crucial for the conducting capacity of the studied systems. The key issue arising from this interaction is a Fermi level pinning effect introduced by dangling interface bonds. Such phenomenon is independent from the width of the considered nanostructures, compromising the importance of confinement in these systems.

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