Reversible Charge‐Polarity Control for Multioperation‐Mode Transistors Based on van der Waals Heterostructures

Abstract

Van der Waals (vdW) heterostructures-in which layered materials are purposely selected to assemble with each other-allow unusual properties and different phenomena to be combined and multifunctional electronics to be created, opening a new chapter for the spread of internet-of-things applications. Here, an O₂ -ultrasensitive MoTe₂ material and an O₂ -insensitive SnS₂ material are integrated to form a vdW heterostructure, allowing the realization of charge-polarity control for multioperation-mode transistors through a simple and effective rapid thermal annealing strategy under dry-air and vacuum conditions. The charge-polarity control (i.e., doping and de-doping processes), which arises owing to the interaction between O₂ adsorption/desorption and tellurium defects at the MoTe₂ surface, means that the MoTe₂ /SnS₂ heterostructure transistors can reversibly change between unipolar, ambipolar, and anti-ambipolar transfer characteristics. Based on the dynamic control of the charge-polarity properties, an inverter, output polarity controllable amplifier, p-n diode, and ternary-state logics (NMIN and NMAX gates) are demonstrated, which inspire the development of reversibly multifunctional devices and indicates the potential of 2D materials.