▎ 摘　　要

A model to calculate the DC characteristics of large-area graphene field-effect transistors is presented. It applies the carrier-density-dependent quantum capacitance to calculate the carrier density, uses a steady-state velocity-field characteristics with soft saturation to describe carrier transport, and takes the carrier density dependence of the saturation velocity into account. Different from previous approaches to model graphene transistors, here the DC characteristics are obtained by feeding a drain current into the device and calculating the drain voltage for a given gate bias. The modeling results are compared with experimental data and very good agreement is obtained. (C) 2011 American Institute of Physics. [doi:10.1063/1.3606583]