Enhanced performance of graphene by using gold film for transfer and masking process

In this study, we tried to reduce the organic contamination of graphene. This organic contamination most likely occurs during the graphene transfer and lithography steps, which in turn degrades the quality of the graphene. Inorganic Au film was applied for Au-assisted transfer instead of the conventional thin poly(methyl methacrylate), and a new fabrication process using the Au-film for the transfer and masking layer was designed in order to minimize the contamination of graphene from organic residues. As a result, we demonstrated that the overall qualities of the transferred graphene film and graphene transistors have been highly improved. These improvements include an enhancement of mobility, and a decrease of defects, unintentional doping, contact resistance, and sheet resistance.