Screening and interlayer coupling in multilayer graphene field-effect transistors.

Abstract

With the motivation of improving the performance and reliability of aggressively scaled nanopatterned graphene field-effect transistors, we present the first systematic experimental study on charge and current distribution in multilayer graphene field-effect transistors. We find a very particular thickness dependence for I(on), I(off), and the I(on)/I(off) ratio and propose a resistor network model including screening and interlayer coupling to explain the experimental findings. In particular, our model does not invoke modification of the linear energy-band structure of graphene for the multilayer case. Noise reduction in nanoscale few-layer graphene transistors is experimentally demonstrated and can be understood within this model as well.