A Fitting Model for Asymmetric I-V Characteristics of Graphene Field-Effect Transistors for Extraction of Intrinsic Mobilities

TL;DR

This paper introduces a fitting model for the asymmetric I-V characteristics of graphene FETs, enabling accurate extraction of intrinsic mobilities and device parameters, which improves understanding of device behavior.

Contribution

The paper presents a novel model that accounts for asymmetries in G-FET I-V curves due to thermionic emission and tunneling, facilitating precise parameter extraction.

Findings

Model accurately fits experimental I-V data

Enables extraction of intrinsic mobility and device parameters

Demonstrates effectiveness on graphene FETs with SiC substrates

Abstract

A fitting model is developed for accounting the asymmetric ambipolarities in the I-V characteristics of graphene field-effect transistors (G-FETs) with doped channels, originating from the thermionic emission and interband tunneling at the junctions between the gated and access regions. Using the model, the gate-voltage-dependent intrinsic mobility as well as other intrinsic and extrinsic device parameters can be extracted. We apply it to a top-gated G-FET with a graphene channel grown on a SiC substrate and with SiN gate dielectric that we reported previously, and we demonstrate that it can excellently fit its asymmetric I-V characteristic.