Effect of Interfacial Defects on the Electronic Properties of MoS$_2$ Based Lateral T-H Heterophase Junctions

TL;DR

This study investigates how interfacial point defects influence electronic transport in MoS₂ heterojunctions, revealing that certain vacancies can significantly enhance charge flow by creating new conduction pathways.

Contribution

It provides first-principles insights into defect effects on electronic transport at MoS₂ phase interfaces, highlighting defect-induced transmission improvements.

Findings

Vacancies at the interface can increase current by two orders of magnitude.

Point defects act as scattering centers in semiconducting MoS₂.

Defects modify electronic densities, opening new conduction channels.

Abstract

The coexistence of semiconducting (2H) and metallic (1T) phases of MoS$_{2}$ monolayers have further pushed their strong potential for applications in the next generation of electronic devices based on the two-dimensional lateral heterojunctions. Structural defects have considerable effects on the properties of these 2D devices. In particular, the interfaces of two phases are often imperfect and may contain numerous vacancies created by phase engineering techniques, e.g. under the electron beam. Here, the transport behaviors of the heterojunctions in the existence of point defects are explored by means of first-principles calculations and non-equilibrium Green's function approach. While vacancies in semiconducting MoS$_{2}$ act as scattering centers, their presence at the interface improves the flow of the charge carriers. In the case of $V_{Mo}$, the current has been increased by two orders of magnitude in comparison to the perfect device. The enhancement of transmission was explained by changes in the electronic densities at the T-H interface, which open new transport channels for electron conduction.