Tunneling transport in WSe2-MoS2 heterojunction transistor enabled by a two-dimensional device architecture

Heterojunctions made of two-dimensional (2D) semiconducting materials provide promising properties for the realization of tunnel field effect transistors (TFETs). The absence of dangling bonds allows the formation of sharp hetero-interfaces, which enables the reduction of parasitic components arising due to interface traps. In this work, we demonstrate band-to-band tunneling (BTBT) between layers of WSe2 and MoS2 that are contacted with few-layered graphene (FLG) on both sides of the junction and completely encapsulated with hexagonal boron nitride (h-BN). Additionally, we also use the FLG as a gate electrode, which allows us to realize devices made entirely of different 2D materials. We observe negative differential resistance (NDR) confirming the tunneling transport in our devices showing the potential in terms of further optimization.