Theoretical limit of how small we can make MoS2 transistor channels

Abstract

As the size of electronic devices is reduced below 3 nm, contact resistance and tunnel leakage current have become crucial factors affecting device performance. The 2D material MoS2 is a potential semiconductor to substitute conventional silicon. In this work, the density functional theory combined with the non-equilibrium Green’s function was used to simulate the transport properties of 2H semiconductor phase MoS2 connected to 1T metal phase MoS2 lead. It is found that when the channel length is greater than or equal to 2.736 nm, the leakage current can be negligible, marking this length as miniaturization limit for a conventional transistors or diodes. When the channel length is smaller than 2.736 nm, the transport is dominated by the direct tunneling. The junctions can be used to design the devices based on the tunneling effect.