Low-temperature growth of epitaxial 3C-SiC films on the just cut and 4° off-Si(111) substrates were performed by gas source molecular beam epitaxial method. Also the irradiation effect of ArF laser was briefly examined. Two kinds of gaseous combinations such as SiHCl3-C2H4 and SiHCl3-C3H8 systems were used to achieve the stoichiometric growth at low temperature. These gases were first thermally cracked at 1000°C and deposited on the substrates. From detailed examinations of the reaction mechanism for this growt method, we concluded that the growth was performed under the conditions of a three-temperature method of MBE in both gaseous systems. Using these cracked species, 3C-SiC films having good crystallinity could be grown at 1000 and 800°C in the SiHCl3-C2H4 and SiHCl3-C3H8 systems, respectively. Currently, it seems that the growth temperature of 800°C is the lowest as compared with other works. We consider that such a low-temperature growth can be performed by the reactions of cracked species at the hollow bridge sites which exist on (111) terraced surface. The ArF laser irradiation was found to enhance the SiC crystallization reaction. © 1990.