4H-SiC substrates were annealed at 1500 °C for 30 min in 0.01 MPa Ar gas flow to make a graphene film. To clarify the effect of Al ion implantation and pre-plasma treatment, the graphene was fabricated on four different kinds of SiC substrates: without plasma treatment, with plasma treatment, Al ion-implanted without plasma treatment and Al ion-implanted with plasma treatment. The graphene films were analyzed by AFM and Raman spectroscopy. The Al ion implanted sample, which was then processed by CF4 plasma, showed small surface roughness of 3.49 nm (RMS), while the sample without CF4 plasma treatment showed large surface roughness of 8.41nm. Similar results were also observed for SiC samples without Al ion implantation. In Raman spectra, strong D-band, G-band and 2D-band signals were detected on both ion-implanted samples after annealing at 1500 °C, but weak D-band were observed on both samples without Al ion implantation. Raman mapping (2D-FWHM) showed that the graphene on ion-implanted SiC treated with CF4 plasma was more homogeneous than the one without CF4 plasma treatment. Hall measurements for SiC without Al ion implantation showed that graphene on SiC treated with CF4 plasma has higher mobility (389 cm2/Vs) than that without plasma treatment (136 cm2/Vs). Additionally, p-type graphene can be fabricated on Al ion-implanted SiC by CF4 plasma treatment.