The C 1s core level spectroscopy of carbon atoms at the surface SiC/Si-4[degrees] interface

Photoemission studies of the electronic structure of the Cs/nano-SiC/Si(111)-4[degrees] nanointerface are for the first time carried out with the use of synchrotron radiation in the photon energy range 120-450 eV. The in situ experiments are conducted in the case of submonolayer Cs coating of the surface of an epitaxial SiC layer grown on the vicinal surface Si(111)-4[degrees] by a new method of substrate-atom substitution. Modification of the valence-band spectra and the C 1s and Si 2p core levels is studied. The appearance of Cs-induced surface states, with binding energies of 1.2 and 7.4 eV, and a sharp change in the spectrum of the C 1s core level with the appearance of two additional modes are found. The evolution of the spectra shows that the Cs/nano-SiC/Si(111)-4[degrees] interface is formed due to charge transfer from Cs adatoms to surface atoms at terraces and steps of the vicinal surface. It is found that the structure of the C layer is nontrivial and involves energetically different carbon states. DOI: 10.1134/S1063782616100080