STUDY OF THE INFLUENCE OF SOLVENT ON TRANSMISSION QUALITY GRAPHENE

The standard methods of transferring graphene onto semiconductor substrates apply acetone to solve the layer of polymethyl methacrylate (PMMA) on the surface of graphene layer at the end of 'wet transfer process'. During this process, however, impurities on the order of nanometres get entrapped and have a subsequent negative effect on the practical utilization of graphene in the field of optoelectronics. To optimize the wet transfer of graphene using PMMA as a supporting polymer, several solvents were compared in terms of resulting contamination. The solvents subjected to the research included: acetone, chloroform, dimethyl succinate (DMG), and n-ethyl pyrrolidone (NEP). The lowest graphene contamination at the end of transfer process was achieved with NEP solvent, which was studied using atomic force microscopy.