Anisotropic band alignment and transport in TMDC junctions with 1T’–2H edge contacts

• 1T'-MX 2 /2H-MX 2 homojunctions exhibit anisotropic band alignment with a lower zigzag-direction Schottky barrier. • Lower Schottky barrier in zigzag direction yields higher current than armchair, showing strong transport anisotropy. • The MoTe 2 FET demonstrates anisotropic transport with higher current but lower on/off ratio in the zigzag direction at 0.6V. Transition metal dichalcogenides (TMDCs) exhibit remarkable properties and hold a crucial position in the field of materials science. These compounds not only display rich polymorphism but also possess unique electronic structures that endow them with significant anisotropy. By combining density functional theory with non-equilibrium Green’s function, we investigated the anisotropic band alignment in 1T’-MX 2 /2H-MX 2 homojunctions. It was discovered that the zigzag direction has a relatively lower Schottky barrier compared to the armchair direction. We used MoTe 2 as an example to construct a field-effect transistor. The lower Schottky barrier in the zigzag direction enables the current in this direction to be consistently higher than that in the armchair direction. However, at V ds = 0.6 V, the on/off ratio is lower along the zigzag direction compared to the armchair orientation.