RF Performance Projections of Graphene FETs vs. Silicon MOSFETs

TL;DR

This paper compares the RF performance of graphene FETs and silicon MOSFETs, revealing that GFETs lag slightly behind CMOS due to nonlinear capacitance effects, and identifying conditions for GFETs to match CMOS performance.

Contribution

It provides a detailed RF performance comparison between GFETs and silicon MOSFETs using calibrated models, highlighting the impact of nonlinear capacitance on device speed.

Findings

GFETs lag slightly behind CMOS in RF speed.

Nonlinear gate capacitance affects GFET performance.

GFETs need mobility ≥ 3000 cm²/V·s to match CMOS.

Abstract

A graphene field-effect-transistor (GFET) model calibrated with extracted device parameters and a commercial 65 nm silicon MOSFET model are compared with respect to their radio frequency behavior. GFETs slightly lag behind CMOS in terms of speed despite their higher mobility. This is counterintuitive, but can be explained by the effect of a strongly nonlinear voltage-dependent gate capacitance. GFETs achieve their maximum performance only for narrow ranges of VDS and IDS, which must be carefully considered for circuit design. For our parameter set, GFETs require at least {\mu} = 3000 cm2 V-1 s-1 to achieve the same performance as 65 nm silicon MOSFETs.