Dry Transfer Of Graphene To Dielectrics And Flexible Substrates Using Polyimide As A Transparent And Stable Intermediate Layer

We demonstrate the direct transfer of graphene from Cu foil to rigid and flexible substrates, such as glass and PET, using as an intermediate layer a thin film of polyimide (PI) mixed with an aminosilane (3-aminopropyltrimethoxysilane) or only PI, respectively. While the dry removal of graphene by an adhesive has been previously demonstrated-being removed from graphite by scotch tape or from a Cu foil by thick epoxy (similar to 20 mu m) on Si-our work is the first step towards making a substrate ready for device fabrication using the polymer-free technique. Our approach leads to an article that is transparent, thermally stable-up to 350 degrees C -and free of polymer residues on the device side of the graphene, which is contrary to the case of the standard wet-transfer process using PMMA. Also, in addition to previous novelty, our technique is fast and easier by using current industrial technology-a hot press and a laminator-with Cu recycling by its mechanical peel-off; it provides high interfacial stability in aqueous media and it is not restricted to a specific material-polyimide and polyamic acids can be used. All the previous reasons demonstrate a feasible process that enables device fabrication.