High performance and gate-controlled GeSe/HfS2 negative differential resistance device

Abstract

Transition metal dichalcogenides (TMDs) have received significant attention owing to their thickness-dependent folded current–voltage (I_ds–V_ds) characteristics, which offer various threshold voltage values. Owing to these astonishing characteristics, TMDs based negative differential resistance (NDR) devices are preferred for the realization of multi-valued logic applications. In this study, an innovative and ground-breaking germanium selenide/hafnium disulfide (p-GeSe/n-HfS₂) TMDs van der Waals heterostructure (vdWH) NDR device is designed. An extraordinary peak-to-valley current ratio (≈5.8) was estimated at room temperature and was used to explain the tunneling and diffusion currents by using the tunneling mechanism. In addition, the p-GeSe/n-HfS₂ vdWH diode was used as a ternary inverter. The TMD vdWH diode, which can exhibit different band alignments, is a step forward on the road to developing high-performance multifunctional devices in electronics.