LOW-TEMPERATURE GROWTH OF SINGLE-CRYSTALLINE CUBIC SIC ON SI(111) BY SOLID SOURCE MOLECULAR-BEAM EPITAXY

Single-crystalline cubic SiC layers have been grown on Si(111) substrates by molecular beam epitaxy (MBE) using graphite and silicon solid sources at relatively low substrate temperatures (800-degrees-C). The growth process employs initial carbonization of the (111) Si surface followed by direct deposition of both Si and C. Reflection high energy electron diffraction (RHEED), X-ray diffraction, cross-sectional and plan-view transmission electron microscopy (TEM), Auger electron spectroscopy (AES), and optical Nomarski microscopy were used to characterize the films. Atomic ratio of Si to C during the growth was found to be critical in terms of the crystalline quality as well as surface morphology of the films. To the extent of the instrumental accuracy, AES shows the SiC films to be stoichiometric. X-Tay diffraction and TEM measurements confirm the crystalline nature of the SiC films.