Growth of large area graphene from sputtered films

Techniques for mass-production of large area graphene using an industrial scale thin film deposition tool could be the key to the practical realization of a wide range of technological applications of the material. Here we demonstrate the growth of polycrystalline graphene from sputtered carbon and metallic layers with in-situ or ex-situ rapid thermal processing. It was found that graphene always grows on the top surface of the stack, in close contact with the Ni or Ni-silicide. Raman spectra typical of high quality exfoliated monolayer graphene were obtained for samples under optimised conditions. A fast cooling rate was found to be essential to the formation of monolayer graphene. Samples with Ni atop SiC produced the best monolayer graphene spectra with ~40% surface area coverage, whereas samples with Ni below SiC produced poorer quality graphene but 99% coverage. The flexibility of the sputtering process allows further optimization of the growth, with possibility of transferring the graphene to any insulator substrate in vacuum. We present a potential route for the production of graphene-on-insulator wafers, which would facilitate easy integration of graphene into modern semiconductor device process flows.