Graphene films grown at low substrate temperature and the growth model by using MBE technique

By depositing atomic C atoms on the grained Cu foil by using molecular beam epitaxy technique (MBE), high-quality graphene is obtained at low substrate temperature 300 °C. A model of initial graphene flake formation as crystal seeds and following lateral graphene growth is established to explain the growth mechanisms. After atomic C atom deposition, no significant difference is observed before and after MBE growth. The results suggest that the deposition of atomic C atoms will not improve the crystalline quality of pre-formed C films. The low substrate temperature required would be advantageous for the practical application of graphene.

► Large-area graphene films are grown by using the MBE technique. ► Low-temperature growth can be easily achieved by using this approach. ► Choice of substrates is a key issue for graphene growth by using MBE.