The growth mechanism of SiC film on a Si(111)-(7×7) surface by C₆₀ precursor studied by photoelectron spectroscopy

We have investigated the growth mechanism of SiC film by the thermal reaction of C₆₀ molecules adsorbed on a Si(111)-(7×7) surface using photoelectron spectroscopy. The growth of SiC film, performed by repeating the sample annealing at 1370 K following the adsorption of C₆₀ molecules, is confirmed by the profile of the valence spectrum. The bonding nature between C₆₀ molecules and the SiC surface is considered to have a covalent character at 300 and 670 K, and both covalent and ionic characters at 870 K by the thermal-dependent valence and C 1s core level spectra of a 1 monolayer C₆₀ film adsorbed on SiC. Furthermore, we determined that the breaking of the C₆₀ cage and the formation of SiC occurred at 1070 K, i.e. at a temperature 100 K lower than that on a Si(111) surface.