Gaseous Catalyst Assisted Growth of Graphene on Silicon Carbide for Quantum Hall Resistance Standard Device

Direct growth of graphene on silicon carbide (SiC) is a very promising method for preparing high-quality graphene. However, high quality single crystal epitaxial graphene films on SiC always form at a temperature higher than 1800 degrees C. Here, the synthesis of graphene on the silicon surface (0001) of SiC at approximate to 1300 degrees C by gaseous catalyst-assisted chemical vapor deposition (CVD) method is reported. As the step height of terraces on SiC surface can influence the performance of graphene Hall devices, low-temperature growth of graphene benefits for keeping the steps of the SiC surface at a small height, which can be achieved by a pre-treatment before growth. A graphene quantum Hall resistance standard (G-QHRS) device fabricated on the SiC surface with a small step height of approximate to 0.5 nm exhibits an accuracy of 1.15 x 10(-8) and a reproducibility of 3.6 x 10(-9) within 7 days in the measurement of quantum resistance at B = 6 T and T = 4.5 K. The gaseous catalyst-assisted CVD on SiC is an effective scalable growth approach that produces high-quality graphene for the resistance metrology, and it represents a promising step toward a low magnetic field QHRS setting the basis of low-cost and transportable QHRS in a near future.