Ultrahigh conductivity of large area suspended few layer graphene films

Room-temperature (atmospheric-pressure) electrical conductivity measurements of wafer-scale, large-area suspended (few layer) graphene membranes with areas up to 1000 mu m(2) (30 mu m x 30 mu m) are presented. Multiple devices on one wafer can be fabricated with high yield from the same chemical vapor deposition grown graphene sheet, transferred from a nickel growth substrate to large opening in a suspended silicon nitride support membrane. This represents areas two to orders of magnitude larger than prior transport studies on any suspended graphene device (single or few layer). We find a sheet conductivity of similar to 2500 e(2)/h (or about 10 Omega/sq) of the suspended graphene, which is an order of magnitude higher than any previously reported sheet conductance of few layer graphene. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4772797]