Characterization of SiC buffer layer formation by reaction of Si(100) surface with methane plus hydrogen plasma

This work, combining in situ surface science techniques (x-ray photoemissio n spectroscopy and reflection high-energy electron diffraction) and ex situ analytical techniques (atomic force microscopy and infrared absorption spe ctroscopy), studies the formation of an SiC buffer layer on Si(100) using r adicals of methane molecules obtained in a low-power-density glow discharge plasma. An analysis of C 1s and Si 2p core-level shifts combined with exam ination of the valence-band curves suggests that the buffer layers obtained are stoichiometric The early stage of SiC nucleation was observed by atomi c force microscopy and reflection high-energy electron diffraction, The res ults reveal that three-dimensional epitaxial islands nucleate at the earlie st growth stage, showing a further Volmer-Weber growth until the formation of a carbon-rich surface, The sequence of events that occur during silicon surface carbonization will be discussed on the basis of a reported model. C opyright (C) 2000 John Wiley & Sons, Ltd.