A Symmetric Tunnel Field-Effect Transistor Based on MoS2/Black Phosphorus/MoS2 Nanolayered Heterostructures

The fast-developing information technology has imposed urgent need for effective solutions to overcome the increasing power density in further scaled electronic devices and systems. The tunnel field-effect transistor (TFET) built with two-dimensional (2D) semiconductors has been widely studied due to its steep-slope switching capability with ultrathin channel. In this work, a symmetric TFET has been fabricated using the MoS2/black phosphorus/MoS2 heterostructure as the channel material. The TFET device exhibits bidirectional current flow which is distinguished from the conventional asymmetric TFET geometry. Upon the application of top gate structure, the devices show sharp turn-on behavior which originated from the transport properties based on the band-to-band tunneling (BTBT) mechanism. By engineering of the top gate materials, a subthermionic subthreshold slope (SS) below 60 mV/dec at room temperature has been achieved, offering a new pathway to lower the power supply and power density in future integrated circuits based on novel 2D materials.