Surface corrugation and stacking misorientation in multilayers of graphene on Nickel

Abstract: Graphene films were grown on thin polycrystalline Ni using a buried amorphous carbon (a-C) layer as C source. Rapid thermal processes (RTP) at temperatures from 600 to 800 degrees C were used to promote C diffusion into Ni and its subsequent segregation on Ni surface, during the sample cool down. RIP at 800 degrees C was the optimal condition for graphene film formation. Micro-Raman spectroscopy showed that the grown film is mostly composed by multilayers of graphene. Atomic force microscopy showed that the film presents peculiar corrugations (wrinkles), isotropically oriented and with heights ranging from from similar to 1 to similar to 15 nm. Selected area diffraction by transmission electron microscopy on the MLG membranes shows a rotational disorder between the stacked graphene layers.