Residue-free suspended graphene transferred by perforated template.

A residue-free transfer method for graphene is proposed in this study, especially for the fabrication of suspended structures. Using perforated polymer templates, graphene can be precisely transferred onto the specific position in the perforated target SiO/Si substrates without the need for polymer removal and the subsequent thermal annealing process. The surface of the transferred graphene by the proposed method was analyzed and corroborated via Raman spectroscopy, Fourier transform infrared spectroscopy, transmission electron microscopy. The results of these analyses suggest that the graphene surface has no polymeric residues resulting from the transfer process. The proposed method provides a powerful approach for the transfer of 2D materials and it enables the exploitation of their suspended structures for device applications as well as the physical characterizations without worry on the effect of contaminants.