Boltzmann Switching MoS2 Metal–Semiconductor Field‐Effect Transistors Enabled by Monolithic‐Oxide‐Gapped Metal Gates at the Schottky–Mott Limit

Abstract A gate stack that facilitates a high‐quality interface and tight electrostatic control is crucial for realizing high‐performance and low‐power field‐effect transistors (FETs). However, when constructing conventional metal‐oxide‐semiconductor structures with two‐dimensional (2D) transition metal dichalcogenide channels, achieving these requirements becomes challenging due to inherent difficulties in obtaining high‐quality gate dielectrics through native oxidation or film deposition. Here, a gate‐dielectric‐less device architecture of van der Waals Schottky gated metal–semiconductor FETs (vdW‐SG MESFETs) using a molybdenum disulfide (MoS2) channel and surface‐oxidized metal gates such as nickel and copper is reported. Benefiting from the strong SG coupling, these MESFETs operate at remarkably low gate voltages, <0.5 V. Notably, they also exhibit Boltzmann‐limited switching behavio…