Atomic threshold-switching enabled MoS2 transistors towards ultralow-power electronics

Qilin Hua,Guoyun Gao,Junlu Sun,Zhong Lin Wang,Chunsheng Jiang,Weiguo Hu,He Qian,Huaqiang Wu,Qijun Sun,Jinran Yu,Renrong Liang,Weijun Cheng,Bin Gao,Taiping Zhang

doi:10.1038/s41467-020-20051-0

Abstract

Power dissipation is a fundamental issue for future chip-based electronics. As promising channel materials, two-dimensional semiconductors show excellent capabilities of scaling dimensions and reducing off-state currents. However, field-effect transistors based on two-dimensional materials are still confronted with the fundamental thermionic limitation of the subthreshold swing of 60 mV decade−1 at room temperature. Here, we present an atomic threshold-switching field-effect transistor constructed by integrating a metal filamentary threshold switch with a two-dimensional MoS2 channel, and obtain abrupt steepness in the turn-on characteristics and 4.5 mV decade−1 subthreshold swing (over five decades). This is achieved by using the negative differential resistance effect from the threshold switch to induce an internal voltage amplification across the MoS2 channel. Notably, in such devices, the simultaneous achievement of efficient electrostatics, very small sub-thermionic subthreshold swings, and ultralow leakage currents, would be highly desirable for next-generation energy-efficient integrated circuits and ultralow-power applications.

Highlights

Power dissipation is a fundamental issue for future chip-based electronics
The seamless device architecture based on a 2D field-effect transistors (FETs) and threshold switch (TS) may realize the simultaneous achievement of efficient electrostatic control, small sub-thermionic subthreshold swing (SS), and low leakage current, leading to efficiently minimizing power dissipation
The common HfO2 thin film is deposited with atomic layer deposition (ALD), functioning as both the dielectric layer of the FET and the electrolyte of the TS

Summary

Introduction

Power dissipation is a fundamental issue for future chip-based electronics. As promising channel materials, two-dimensional semiconductors show excellent capabilities of scaling dimensions and reducing off-state currents. We present an atomic threshold-switching field-effect transistor constructed by integrating a metal filamentary threshold switch with a two-dimensional MoS2 channel, and obtain abrupt steepness in the turn-on characteristics and 4.5 mV decade−1 subthreshold swing (over five decades). This is achieved by using the negative differential resistance effect from the threshold switch to induce an internal voltage amplification across the MoS2 channel. In such devices, the simultaneous achievement of efficient electrostatics, very small sub-thermionic subthreshold swings, and ultralow leakage currents, would be highly desirable for nextgeneration energy-efficient integrated circuits and ultralow-power applications. The proposed ATS-FET has great potential to be extended to scalable and monolithic steep-slope transistor arrays and is of great significance in energy-efficient and high-performance electronic switches with ultralow-power dissipation

Methods

Results

Conclusion