Influence of SiO₂ or h-BN substrate on the room-temperature electronic transport in chemically derived single layer...

The substrate effect on the electronic transport of graphene with a density of defects of about 0.5% (^0.5%G) is studied. Devices composed of monolayer ^0.5%G, partially deposited on SiO₂ and h-BN were used for transport measurements. We find that the ^0.5%G on h-BN exhibits ambipolar transfer behaviours under ambient conditions, in comparison to unipolar p-type characters on SiO₂ for the same flake. While intrinsic defects in graphene cause scattering, the use of h-BN as a substrate reduces p-doping.