Modeling of transistors based on lateral heterostructures of 2D materials

Transition Metal Dichalcogenides, TMD, represent a class of materials that can be made atomically thin, like graphene, but still show a bandgap. The presence of a bandgap allows TMDs to be investigated in digital electronics applications, since their thinness makes them viable for devices with channel lengths of a few nanometers which can be used for transistors based on lateral and vertical heterostructures. This work studies the modeling and electrical simulation of a transistor based on a lateral heterostructure of TMD composed of NbS2 for the contact and WSe2 for the channel. The modeling of the structure was made through a tight-binding description of the materials, whose parameters were extracted from Density Functional Theory results. The tight-binding description was fed to NanoTCADViDES, a code developed at University of Pisa which solves the Schrödinger-Poisson equations in the Non Equilibrium Green’s Function formalism