Nucleation and growth of single crystal graphene on hexagonal boron nitride

Direct graphene growth was demonstrated on exfoliated hexagonal boron nitride (h-BN) single crystal flakes by low pressure CVD. The size of the hexagonal single crystal graphene domain increases with deposition time, with maximum size of ∼270 nm. Most domains were found to nucleate at screw dislocation sites, and a step-flow growth mechanism was observed at atomic steps on the h-BN surface. Understanding the nucleation and growth mechanisms is an important step towards the synthesis of large single crystal graphene on h-BN substrates.