ELECTRONIC-STRUCTURE OF SIC-TIC INTERFACES

A theoretical study of the atomic and electronic structure of the SiC-TiC {001} interface was carried out using the linear muffin-tin orbital method in the atomic-sphere approximation. Out of eight ideal structures, the configuration with Ti directly on top of Si atoms of the Si-terminated SiC was found to have the lowest energy. The very high energies of the other configurations indicate that they would require large atomic relaxations if they were to be realized. The layer-projected densities of states were used to analyse the electronic structure associated with the above defined configuration. It is shown to exhibit interface-localized states which are remnants of the surface states. One of these surface states occurs in the bandgap of SiC and is proposed to play an important role in the Schottky-barrier height determination.