Impact of Electrostatic Doping Level on the Dissipative Transport in Graphene Nanoribbons Tunnel Field-Effect Transistors

TL;DR

This study investigates how electrostatic doping levels influence dissipative transport in graphene nanoribbon TFETs, revealing that proper doping engineering can suppress phonon-assisted tunneling and optimize device switching at various temperatures.

Contribution

It demonstrates that doping level engineering can effectively inhibit phonon absorption-assisted tunneling in GNR-TFETs, improving their switching performance.

Findings

Doping levels significantly affect phonon contribution to transport.

Proper doping can suppress phonon-assisted tunneling.

Optimal doping levels depend on temperature for best switching.

Abstract

The impact of electrostatic doping level on the dissipative transport of Armchair GNR-TFET is studied using the Quantum Perturbation Theory (QPT) with the Extended Lowest Order Expansion (XLOE) implementation method. Results show that the doping level of the source and drain sides of the GNR-TFET has a significant impact on the phonon contribution to the carrier transport process. Unlike in other similar studies, where phonons are believed to have a constant detrimental influence on the ION/IOFF ratio and Subthreshold Swing (SS) of the TFET devices due to the phonon absorption-assisted tunneling, we show that by a proper engineering of the doping level in the source and drain, the phonon absorption assisted tunneling can be effectively inhibited. We also show that as temperature increase, the device switching property deteriorates in both the ballistic and dissipative transport regimes, and there exists a temperature-dependent critical doping level where the device has optimal switching behavior.