The contact barrier of a 1T′/2H MoS2 heterophase bilayer and its modulation by adatom and strain: a first-principles study

Abstract

The successful synthesis of a 1T′/2H MoS₂ heterophase bilayer offers potential building blocks for constructing novel nanoelectronic and optoelectronic devices. Here, first principles calculations are applied to explore and modulate its contact nature. The calculated results show a finite Schottky barrier of ∼0.56 eV, and a dominant tunneling barrier of ∼2 eV exists at the contact interface of the 1T′/2H MoS₂ heterophase bilayer. The Schottky barrier can be eliminated by adatoms and strains. Although the two strategies have an insignificant effect on the dominant tunneling barrier, they alter the regions with local potentials lower than that of the inter-layer gap related barrier.