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The growth of SiC on Si(111) substrate was performed by solid-source molecular beam epitaxy (SSMBE).The effects of different deposition rates and Si/C flux ratios on the growth of SiC on Si (111) were investigated by reflection high energy electron diffraction (RHEED), X-ray diffraction (XRD), atomic force microscopy (AFM). The results indicate that there is an optimized Si/C flux ratio. Besides SiC streaks, a (3×3) surface reconstruction can be observed in RHEED of the sample grown at the optimized Si/C ratio and the full width at half maximum (FWHM) of the rocking curve is 1.1°. For the sample grown at lower Si /C flux ratio, there are SiC spots and SiC ring pattern observed by RHEED and the FWHM of the rocking curve of is 2.1°. For the sample grown at higher Si/C flux ratio, the results of RHEED indicate that Si spots coexist with SiC spots and the results of the rocking curve show the FWHM of 1.5°. At the optimized Si/C ratio, there is an optimized deposition rate. At lower rate, the crystal quality is worse and a few voids exist on the surface. In the case of higher deposition rate, the crystallinity is also worse and the voids are fewer. At the optimized deposition rate, the crystallinity is good, but some voids can still be observed. |