Experimental confirmation of suspended few-layered graphene on a Cu substrate grown via the CVD method and correlated with the electrical performance on a PET substrate

Abstract

We present that the Raman 2D and G peak of graphene film fabricated via chemical vapour deposition (CVD) blue-shifts on the relatively even Cu foil domain, showing a rather compressive strain effect compared to the uneven domain. We experimentally figure out that the relaxing compressive strain, to minimize the adhesive interaction between the graphene and the Cu surface, has one of the critical roles in forming suspended few-layered graphene. The nanoscopic conductance investigation also reveals that the current flow is dominantly measured at the uneven nano-terrace domains rather than at the even, further signifying the importance of a detailed underlying Cu surface morphology.