Effect of BN seeds on locating and promoting the initial nucleation of graphene on Cu substrate and its mechanism: A theoretical study

Abstract

The controllable location of graphene nucleation is of great significance for preparing graphene arrays and promoting their applications in microelectronic devices and integrated circuits. In this work, we theoretically explore the effect of introducing BN nanoclusters as nucleation seeds on locating and promoting graphene nucleation on Cu(1 1 1) substrate at an initial stage. It was demonstrated that the edge of BN nanoclusters could act as active sites for C adsorption and aggregation. By introducing BN seeds, the C adsorption energies and nucleation barriers could be largely decreased, while the nucleation rate of graphene significantly increased with respect to the graphene spontaneous nucleation on the Cu(1 1 1) substrate. Therefore, the graphene arrays with large domains could be obtained by pre-preparing the regular BN pattern and controlling the experimental conditions. Theoretical results also indicate that controlling the carbon source in a relatively low concentration is beneficial for amplifying the structural inducing effect of BN seeds. It is expected that the prepared graphene arrays by this method can be directly applied to the graphene-based integrated circuit after the transfer process.