Versatile\nElectronic Devices Based on WSe₂/SnSe₂ Vertical\nvan der Waals Heterostructures

Abstract

Van\nder Waals heterostructures formed by stacking of various two-dimensional\nmaterials are promising in electronic applications. However, the performances\nof most reported electronic devices based on van der Waals heterostructures\nare far away from those of existing (Si, Ge, and III–V bulk\nmaterial based) technologies. Here, we report high-performance heterostructure\ndevices based on vertically stacked tungsten diselenide and tin diselenide.\nDue to the unique band alignment and the atomic thickness of the material,\nboth charge carrier transport and energy barrier can be effectively\nmodulated by the applied electrical field. As a result, the heterostructure\ndevices show superb characteristics, with a high current on/off ratio\nof ∼3 × 10⁸, an average subthreshold slope\nof 126 mV/dec over 5 dec of current change due to band-to-band tunneling,\nan ultrahigh rectification ratio of ∼3 × 10⁸, and a current density of more than 10⁴ A/cm². Furthermore, a small signal half-wave rectifier circuit based on\na majority-carrier-transport-dominated diode is successfully demonstrated,\nshowing great potential in future high-speed electronic applications.