Effect of copper foil annealing process on large graphene domain growth by solid source-based chemical vapor deposition

Controlling the metal catalyst surface structure is a critical factor to achieve growth of large graphene domains. In this prospect, we explored the annealing process to create an oxide layer and subsequent recrystallization of Cu foil for growth of large graphene domain by the atmospheric pressure chemical vapor deposition (AP-CVD) technique. We revealed the transformation of Cu surface crystallographic structures in every step of annealing process by electron back-scattered diffraction analysis. Initially, electroless polished Cu foils are annealed in Ar and then in H₂ atmosphere to obtain a smoother surface with reduced graphene nucleation sites. The transformation of Cu grain structures at various annealing steps was confirmed, where the gas atmosphere and annealing duration have significant influence. Graphene domains with the size more than 560 µm are obtained on the processed Cu surface using polystyrene as solid precursor. It is obtained that the oxidation and recrystallization process of Cu foil surface significantly influence the nucleation density, which enable growth of larger graphene domain in the developed CVD process.