Precision quantization of Hall resistance in transferred graphene

We show that quantum resistance standards made of transferred graphene reach the uncertainty of semiconductor devices, the current reference system in metrology. A large graphene device (150 x 30 mu m(2)), exfoliated and transferred onto GaAs revealed a quantization with a precision of (-5.1 +/- 6.3) . 10(-9) accompanied by a vanishing longitudinal resistance at current levels exceeding 10 mu A. While such performance had previously only been achieved with epitaxially grown graphene, our experiments demonstrate that transfer steps, inevitable for exfoliated graphene or graphene grown by chemical vapor deposition, are compatible with the requirements of high quality quantum resistance standards. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4704190]