Reaction of Si (100) with silane-methane low-power plasma: SiC buffer-layer formation

The formation of a SiC buffer layer on Si (100) at substrate temperature as low as 950 degrees C using radicals of methane molecules obtained in a low -power-density glow-discharge plasma, is presented. The x-ray photoemission spectroscopy and low-energy-yield spectroscopy performed in the constant f inal-state mode suggest that the layers obtained were stoichiometric. To un derstand the mechanism of heteroepitaxial silicon carbide growth, the early stage of SiC nucleation was observed by atomic force microscopy and reflec tion high-energy electron diffraction. The results reveal that three-dimens ional epitaxial crystallites nucleate at the earliest growth stage followed by a further Volmer-Weber growth. (C) 1999 American Institute of Physics. [S0021-8979(99)04620-4].