Formation of graphene is known to be even easier on 4H-SiC(0001 ̅ ) surface due to the absence of the partially sp 3 -bonded interfacial layer (so-called buffer layer) between graphene and SiC . However, only the Si-face affords oriented graphene layers (from 1350 °C at our CVD conditions) , while the graphene layers grown on the C-face are usually randomly rotated with respect to the substrate .