Effect of ion-beam irradiation on the epitaxial growth of graphene via the SiC surface decomposition method

We used scanning tunneling microscopy, low-energy electron diffraction, and Raman spectroscopy to investigate the growth of graphene on 3C-SiC(111)/SiO2/Si(111) surfaces with ion-beam irradiation via the SiC surface decomposition method. We were unable to obtain graphene after annealing the 3C-SiC(111) surface at 1100 °C for 3 min without Ar+ ion-beam irradiation. When a 3C-SiC(111) surface was irradiated with an Ar+ ion beam at an acceleration voltage of 1 keV and an incident angle of 80° and subsequently annealed at 1100 °C for 3 min, graphene formed on the SiC surface. However, when an Ar+ ion beam was used at an incident angle of 70 or 60°, graphene layers were not formed. These results indicate that the breakage of bonds in the surface region of the SiC(111) substrate by ion-beam irradiation promotes the formation of graphene.