Ultrashort Vertical-Channel van der Waals Semiconductor Transistors

Area of Science:

• Materials Science
• Nanotechnology
• Electrical Engineering

Background:

• Atomically thin 2D van der Waals semiconductors are key for next-generation nanoscale field-effect transistors (FETs).
• Demonstrating nanometer-length-scale devices in these materials remains a challenge despite successful large-area synthesis.

Purpose of the Study:

• To fabricate controllable nanometer-scale transistors with ultrashort channel lengths.
• To demonstrate the feasibility of high-density and large-scale fabrication of these devices.

Main Methods:

• Fabrication of vertical channel transistors by inserting an ultrathin insulating spacer between out-of-plane source and drain electrodes.
• Utilizing monolayer MoS2 synthesized via chemical vapor deposition.

Main Results:

• Achieved transistors with a channel length of approximately 10 nm.
• Obtained a large on-current density of ~70 µA µm⁻¹ nm⁻¹ at 0.5 V.
• Demonstrated high on/off ratios ranging from 10⁷ to 10⁹.

Conclusions:

• The study presents a viable method for creating ultrashort 2D vertical channel FETs.
• This approach offers a promising route for complementary metal-oxide-semiconductor-compatible, wafer-scale fabrication of high-density 2D van der Waals transistors.