Research On A New Method Of Clean Transfer Of Graphene

Since first isolated in 2004,graphene has received a lot of attention due to its unique properties.At present,the preparation of high-quality graphene has been achieved by chemical vapor deposition(CVD).In order to realize applications of graphene,it is necessary to separate and transfer the CVD grown graphene from the metal substrate to the target substrate.However,during the transfer process,graphene will come into contact with various pollutants,which makes the transferred graphene film prone to defects and contamination,seriously affecting its performance in applications.Therefore,realizing clean transfer of graphene is a key issue for large-scale industrial application of graphene.In view of the above problems,this paper studies the possible contamination of graphene caused by the traditional wet transfer process,and proposes a graphene transfer method using PVA as the support layer,which can achieve relatively clean graphene1.CVD grown graphene on copper was transferred using polymethyl methacrylate(PMMA)as the support layer.Results of Raman spectrum of the transferred graphene show,that even acetone used to remove PMMA would cause contamination on the transferred graphenedue to the C=O bond.2.In order to solve the contamination problem caused by the traditional PMMA transfer method,polyvinyl alcohol(PVA)/polymethyl methacrylate(PMMA)composite structure was used.This transfer method solves the problem of PMMA residue on the graphene surface,but the effect of acetone on graphene still exists.3.Finally,graphene transfer was performed using only PVA as the support layer.Raman results showed that no PVA,PMMA residues and contamination caused by C=O were found.Compared with the above transfer methods,using only PVA as the support layer can achieve relatively clean transfer of graphene.