Low temperature growth of 3C-SiC crystal by hydrogen radical assisted plasma enhanced chemical vapor deposition

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The objective of this project is to realize the low temperature growth of 3C-SiC and epitaxial growth of it on Si substrates utilizing the hydrogen radicals generated by rf plasma.In 1997, as a result of the experiments of crystal growth by triode plasma CVD method and by hybrid plasma CVD method allow temperature (<1000ﾟC) using dimethyichiorosilane and dimethylsilane as source gases, it became clear that the triode plasma CVD method using dimethylsilane was effective and the crystal growth at 600ﾟCwas possible utilizing the method. The crystal growth of SiC at the low temperature was realized under the conditions of low plasma space potential and low electron temperature (<1eV) in the vicinity of the substrate surface. Reducing the hydrogen ion acceralation at sheath region by the suppression of the rf vibration of plasma space potential , the crystallinity of SiC films was further improved. Epitaxial growth on Si(100) and (111) was also successful at 1000ﾟC.Using the triode plasma CVD method, the surface morphplogy of SiC films was more satisfactory than that grown by thermal CVD method.In 1998, the conditions of the dilution ratio of source gas by hydrogen and the reaction pressure were extensively controlled using the turbo molecular pump, which has high evacuation rate, for the growth of epitaxial SiC films. As a result of this experiment, highly oriented SiC epitaxial films with best crystallinity were obtained at reaction pressure of 0,3 Torr and at high dilution rate of hydrogen (>200). By changing the hydrogen dilution ratio, the residual stress of SiC on Si (111) was able to vary from coinpresive to tensile. By control the hydrogen dilution ratio, SiC epitaxial film on Si substrates with low residual stress was able to be obtained.