Nanopatterned Graphene on a Polymer Substrate by a Direct Peel-off Technique

Abstract

: A graphene (Gr) on a polyimide (PI) polymer film (Gr−PI film), obtained by a direct peel-off technique, is proposed and investigated. Thanks to its high transparency, electrical conductivity, mechanical strength, and chemical durability, the Gr−PI film is an ideal substrate for flexible electronic and optoelectronic devices, including transistors, lightemitting diodes, and plasmonic antennas. It is obtained using a straightforward method. After spin coating and curing a PI film on Gr previously grown on Cu, one can separate the Gr−PI film from the Cu foil thanks to the difference in the adhesive energy between the Gr−Cu and Gr−PI interfaces. The resulting Gr−PI film shows an average electrical sheet resistance ranging from 520 to 860 Ω/sq and a very high optical transmission (>90%), which have allowed the demonstration of a transparent heater. The surface morphology of the Gr−PI film follows that of the Cu foil, with the latter maintaining its surface properties and allowing in this way its reuse in subsequent chemical vapor deposition growth. The me