Electrical Compact Modelling of Graphene Transistors

An electrical compact model for graphene FET device is proposed. Starting from Meric's compact model, a trap model is introduced and the equivalent circuit is improved. We show that traps have an effect on the transconductance and influence consequently most figures of merit in circuit design. The model has been verified by comparison to DC and AC measurements versus bias and frequency on an advanced GFET having a transit frequency of about 10 GHz. Then, the compact model has been used to evaluate the transistor in a circuit context. A LNA has been designed and despite the poor voltage gain of the GFET, the LNA shows interesting performances when input and output matching of the circuit is performed. A power gain of vertical bar S21 vertical bar = 4.2 dB is obtained, the reverse isolation is about vertical bar S12 vertical bar = -10.6 dB, the Rollet stability factor K is 1.25 and the noise figure is 3.9 dB at 800 MHz. (C) 2012 Elsevier Ltd. All rights reserved.