Dissipative Transport and Phonon Scattering Suppression via Valley Engineering in Single-Layer Antimonene and Arsenene Field-Effect Transistors

TL;DR

This paper uses quantum transport simulations to analyze phonon scattering in 2D antimonene and arsenene FETs, demonstrating how valley engineering via uniaxial strain can suppress intervalley scattering and enhance device performance.

Contribution

It introduces a valley engineering strategy with uniaxial strain to reduce phonon scattering, improving 2D FET performance beyond traditional approximations.

Findings

Intervalley and optical phonon scattering dominate transport limitations.

Uniaxial strain removes valley degeneracy, suppressing scattering channels.

Valley engineering improves ON current in 2D FETs.

Abstract

Two-dimensional (2D) semiconductors are promising channel materials for next-generation field-effect transistors (FETs) thanks to their unique mechanical properties and enhanced electrostatic control. However, the performance of these devices can be strongly limited by the scattering processes between carriers and phonons, usually occurring at high rates in 2D materials. Here, we use quantum transport simulations calibrated on first-principle computations to report on dissipative transport in antimonene and arsenene $n$-type FETs at the scaling limit. We show that the widely-used approximations of either ballistic transport or simple acoustic deformation potential scattering result in large overestimation of the ON current, due to neglecting the dominant intervalley and optical phonon scattering processes. We additionally investigate valley engineering strategy [Nano Lett. \textbf{19}, 3723 (2019)] to improve the device performance by removing the valley degeneracy and suppressing most of the intervalley scattering channels via an uniaxial strain along the zigzag direction. The method is applicable to other similar 2D semiconductors characterized by multivalley transport.