Few-layer graphene (FLG) has been prepared by thermal annealing of SiC crystal via the surface Ni-silicidation reactions. Results reveal that the temperature plays an important role for the final FLG quality and the optimized annealing temperature is about 800 °C. The investigation of surface morphology and microstructure for the FLG sample indicates that after the rapid cooling, the carbon atoms will segregate to form the FLG layer and the NiSix particles will congregate on the top surface. The mechanism of the FLG formation on SiC surface assisted by the Ni ultra-thin layer is briefly discussed based on the experimental results.

Graphene layers have been grown on C-terminated 6H-SiC (000-1) substrate by thermal decomposition with the assistance of carbon flux in a solid carbon source molecular beam epitaxy system. Results indicate that the graphene films prepared directly by the reduction of SiC in vacuum chamber are defective and disorder, while appropriate carbon flux added during the graphene growth will favor the graphene layer growth and improve the graphene layer quality. While on the other hand, too much carbon flux will affect the graphene formation and deteriorate the final graphene layer. This carbon flux assisted graphene growth behavior on SiC crystal indicates that the external carbon flux should play an important role for the graphene layer growth during the thermal reduction of SiC in vacuum condition. The mechanism of the graphene layer formed on C-face SiC and the effect of the carbon flux were discussed based on the experimental results.