A physics-based, small-signal model for graphene field effect transistors

In this letter, a small-signal model for the graphene-based field effect transistor based on a physical description of the device’s operation is presented. The small-signal model contains circuit elements similar to classical small-signal models for field effect transistors but these elements differ vastly in their behavior with bias, owing to the different physical behavior of these devices. Intrinsic and extrinsic small-signal models are presented. The high-frequency performance of the models in terms of short-circuit current gain and Mason’s unilateral gain, and associated frequency figures-of-merit, are examined.

► Small-signal model development for graphene FETs. ► Based on quasi-static admittance parameters derived from theoretical operation of the device. ► Unique properties of graphene result in unconventional behavior of elements (gm, CG, gd, CGD). ► Intrinsic and extrinsic frequency performance: high gd limits the operation of the device. ► Effect of varied gate length (L); RG, RS, RD; and μn, μp examined.