Hetero-interface control and atomic layer epitaxy of SiC

Hetero-interface control in an atomic level and subsequent heteroepitaxial growth of cubic(3C)–SiC on Si were achieved using hydrocarbon radicals in gas source molecular beam epitaxy. The number of methyl (CH3) radicals was estimated quantitatively by a threshold-ionization quadrupole mass spectroscopy method. The effects of CH3 radicals on carbonization of a Si surface were discussed relating with the change of surface superstructures revealed by a time-resolved reflection high-energy electron diffraction analysis. Heteroepitaxial growth of SiC on Si was achieved by a combination of carbonization of a Si surface and subsequent crystal growth using hydrocarbon radicals and disilane (Si2H6). A 3C–SiC (3×2) reconstruction can be observed at a suitable flow rate. At a typical flow rate of CH3 radicals, the growth rate was kept constant regardless of the Si2H6 flow rate, which implies an atomic level control of crystal growth using a layer-by-layer growth mode.