High-field Carrier Velocity and Current Saturation in Graphene Field-Effect Transistors

TL;DR

This paper models the output characteristics of graphene FETs using a charge-control approach based on the Boltzmann equation, deriving key expressions and validating them against experimental data without assuming velocity saturation.

Contribution

It introduces a novel analytical model for graphene FETs that accurately predicts their behavior without relying on carrier density-dependent velocity saturation assumptions.

Findings

Good agreement with experimental data

Closed-form expressions for conductance and saturation voltage

Model does not require velocity saturation assumption

Abstract

We obtain the output characteristics of graphene field-effect transistors by using the charge-control model for the current, based on the solution of the Boltzmann equation in the field-dependent relaxation time approximation. Closed expressions for the conductance, transconductance and saturation voltage are derived. We found good agreement with the experimental data of Meric et al. [1], without assuming a carrier density-dependent velocity saturation.