Subthreshold Schottky-barrier transistor based on monolayer molybdenum disulfide

Area of Science:

• Materials Science
• Electrical Engineering
• Nanotechnology

Background:

• The Internet of Things (IoT) requires efficient sensors with precise signal amplification and rapid transmission.
• Thin-film transistors (TFTs) are crucial for IoT interfaces, demanding high voltage gain and wide operating frequency.

Purpose of the Study:

• To develop a novel source-gated transistor (SGT) architecture for high-performance, low-power IoT applications.
• To demonstrate the scalability and performance of MoS2-based SGTs at nanoscale channel lengths.

Main Methods:

• Fabrication of a source-gated transistor (SGT) using chemical vapor deposition (CVD)-grown monolayer MoS2 integrated with thin high-k dielectrics.
• Characterization of transistor performance, including intrinsic gain, output resistance, transconductance, and subthreshold swing, across various channel lengths (LCH).
• Microwave measurements to determine the cut-off frequency and evaluation of a monolithically integrated common-source amplifier.

Main Results:

• Achieved subthreshold operation with high intrinsic gain (>2.4x10^3) and wide operating frequency range, even at an 80 nm channel length (LCH).
• Demonstrated no degradation in gain as LCH scaled from 1000 nm down to 80 nm.
• Observed a high cut-off frequency of 208 MHz in the subthreshold regime and a high amplifier gain of 249 V/V at 0.5 V supply voltage and ~0.17 nW power consumption.

Conclusions:

• The developed MoS2-based SGT architecture offers a promising universal solution for high-gain, high-frequency, and ultra-low-power applications.
• The transistor's performance scalability down to 80 nm LCH highlights its potential for next-generation IoT devices.
• This work paves the way for advanced integrated circuits operating efficiently in the subthreshold regime.