Re-nucleation and Etching of Graphene During the Cooling Stage of Chemical Vapor Deposition

Graphene growth on copper foil via chemical vapor deposition (CVD) is extensively used because the low carbon solubility of Cu leads to uniform, single-layer graphene formation. However, re-nucleation and etching, which dramatically weaken the quality of graphene, occur in some cooling conditions. CVD graphene growth on Cu is influenced by the cooling stage. In this work, the role of cooling in CVD graphene domain growth on Cu foil was studied, and the effects of cooling rate and atmosphere on the growth of graphene during the cooling stage were investigated. The re-nucleation and etching of graphene domains were observed in some cooling processes. These phenomena occur due to the processes related with the varying cooling rate and hydrogen (H2) and methane (CH4) concentrations in the reactor.