Modeling Contact Resistivity in Monolayer Molybdenum disulfide Edge contacts

We calculate the resistivity of Schottky edge contacts between a metal and a transition-metal dichalcogenide (TMD) thin layer. The electrostatic potential is obtained by solving numerically the Poisson equation; the transmission probability is computed using the Wentzel–Kramers–Brillouin (WKB) approximation using the full-band density of states obtained from density functional theory (DFT); the effect of the image force is obtained analytically using the Green’s function for the Poisson equation with boundary conditions appropriate to the geometry we have considered. We find that the dielectric environment surrounding the 2D layer largely controls the electrostatics and image-force barrier lowering. Low-resistance metal-TMD Schottky edge contacts are obtained using low-κ top and bottom insulators.