Effect of interfacial defects on the electronic properties of MoS2 based lateral T–H heterophase junctions

Abstract

The coexistence of semiconducting (2H) and metallic (1T) phases of MoS₂ monolayers has further pushed their strong potential for applications in the next generation of electronic devices based on 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 an electron beam. Here, the transport behaviors of the heterojunctions with the existence of point defects are explored by means of first-principles calculations and non-equilibrium Green's function approach. While vacancies in semiconducting MoS₂ 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.