Modeling and Characterization of a Top Gated Graphene FET for RF Applications

In this research paper, we have developed a circuit model for a top-gated graphene based field effect transistor (GFET) for radio frequency applications. The quantum capacitance (C Q ) of the proposed GFET model depends on the oxide thickness and internal capacitances. The carrier transport model based on drift–diffusion characteristic is used to model the drain current (I DS ) for all operating regions of a GFET. The proposed model has a small signal current gain (H 21) of 200 dB and a transit frequency (f T ) of 90 GHz. Analytical formulas for f T , I DS and C Q are presented which are used for hand calculation of these parameters and are also implementable in circuit level simulators. The model was implemented in Agilent Advance Design Systems. The simulation results show a favorable agreement with the experimental results of the previously published work on GFET models.