Extraction of the voltage-dependent quantum capacitance and kinetic inductance of GNRFETs: a first-principles study

Graphene nanoribbon field effect transistors (GNRFETs) are prominent candidates for the near future nanoelectronics technology. In thiswork, a sample GNRFET is simulated utilizing density functional theory with nonequilibrium Green's function formalism (NEGF) to obtain the current-voltage relationship, the variation of the channel charge and the electrostatic potential with respect to applied voltage. It is shown that a 5th order polynomial model, which can be utilized in circuit design tools, accurately models the current-voltage relationship of GNRFETs. More importantly, the variations of the kinetic inductance, quantum capacitance and the Fermi velocity dependent on both the source-drain (V-DS) and source-gate voltages (V-GS) are extracted. Numerical values of these parameters are found to be consistent with the theoretical and experimental average values existing in the literature. The paper is concluded with the discussion of the voltage-dependencies of the kinetic inductance and the quantum capacitance for the circuit design using GNRFETs.