GROWTH OF SIC FILMS OBTAINED BY LPCVD

This paper reports the results of a systematic study of the influence of deposition conditions on the morphology of films grown using a tetr amethylsilane Si(CM3)(4) precursor in a hot-wall, low pressure, chemic al vapor deposition system at the temperature range 900-1150 degrees C . Most of the SiC films were deposited on a thin a-SiO2 layer, thermal ly grown on Si(001) wafers. Characterization of the SiC films was perf ormed by X-ray diffraction, scanning and transmission electron microsc opy, ellipsometry, profilometry, electron microprobe analysis with a w avelength dispersive spectrometry detection system, and X-ray photoele ctron spectroscopy. The results obtained on the kinetics of growth con cern the change in the growth rate and the evolution of the preferenti al [111] orientation of the polycrystalline films with the deposition conditions. The general characteristics of the polycrystalline films a re their columnar structure, which is related with the very strong [11 1] preferred orientation, and the formation of microtwins, having the twin planes perpendicular to the direction of growth. (C) 1997 Elsevie r Science S,A.