2018/07/30 by Tommaso Cavallucci, Cavallucci, Tommaso, Valentina Tozzini +1 · 2 citations
Engineering · Materials Science · #Boron and Carbon Nanomaterials Research #FOS: Physical sciences #Graphene research and applications #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Silicon Carbide Semiconductor Technologies
paper · pdf · doi:10.48550/arxiv.1807.11230
openalex publication_date 2018/07/30 · openalex created_date 2022/08/04 · openalex updated_date 2026/07/28
The buffer carbon layer obtained in the first instance by evaporation of Si\nfrom the Si-rich surfaces of silicon carbide (SiC) is often studied only as the\nintermediate to the synthesis of SiC supported graphene. In this work, we\nexplore its intrinsic potentialities, addressing its structural and electronic\nproperties by means Density Functional Theory. While the system of corrugation\ncrests organized in a honeycomb super-lattice of nano-metric side returned by\ncalculations is compatible with atomic microscopy observations, our work\nreveals some possible alternative symmetries, which might coexist in the same\nsample. The electronic structure analysis reveals the presence of an electronic\ngap of ~0.7eV. In-gap states are present, localized over the crests, while\nnear-gap states reveal very different structure and space localization, being\neither bonding states or outward pointing p orbitals and unsaturated Si\ndangling bonds. On one hand, he presence of these interface states was\ncorrelated with the n-doping of the monolayer graphene subsequently grown on\nthe buffer. On the other hand, the correlation between their chemical character\nand their space localization is likely to produce a differential reactivity\ntowards specific functional groups with a spatial regular modulation at the\nnano-scale, opening perspectives for a finely controlled chemical\nfunctionalization.\n