The synthesis of Bernal-stacked multilayer graphene over large areas is intensively investigated due to the value of this material's tunable electronic structure, which makes it promising for use in a wide range of optoelectronic applications. Multilayer graphene is typically formed via chemical vapor deposition onto a metal catalyst, such as Ni, a Cu-Ni alloy, or a Cu pocket. These methods, however, require sophisticated control over the process parameters, which limits the process reproducibility and reliability. Here, a new synthetic method for the facile growth of large-area Bernal-stacked multilayer graphene with precise layer control is proposed. A thin Ni film is deposited onto the back side of a Cu foil to induce controlled diffusion of carbon atoms through bulk Cu from the back to the front. The resulting multilayer graphene exhibits a 97% uniformity and a sheet resistance of 50 Ω sq-1 with a 90% transmittance after doping. The growth mechanism is elucidated and a generalized kinetic model is developed to describe Bernal-stacked multilayer graphene growth by the carbon atoms diffused through bulk Cu.
Keywords: Bernal stacking; carbon diffusion; copper; multilayer graphene.
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