Drastic change in surface electronic properties and creation of a new carbon-based nanostructure on the vicinal SiC(111)-4° surface

Abstract

Novel carbon based nanostructure on the vicinal SiC(111)-4° surface has been found as effect of Cs adsorption. The SiC(111)-4°sample was grown by method of epitaxy of low-defect unstressed nanoscaled silicon carbide films on vicinal Si(111)-4° substrate. Electronic structure of the SiC(111)-4° surface and the Cs/SiC(111)-4°interface has been detailed studied in situ in an ultrahigh vacuum using synchrotron-based photoelectron spectroscopy. The C 1s and Si 2p core level spectra have been investigated as a function of Cs submonolayer coverage. A unique fine structure of the C 1s core level spectrum was revealed to appear under Cs atomic layer deposition. The effect was ascertained and shown to be originated from the interaction of the silicon vacancy with adsorbed Cs atoms that leads to both the redistribution of electron density and surface reconstruction with formation of a new type of the C-enriched aromatic-like nanostructure.