All van der Waals Semiconducting PtSe₂ Field Effect Transistors with Low Contact Resistance Graphite Electrodes

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Contact resistance is a major hurdle in developing high-performance 2D electronic devices.
• Large Schottky barrier heights and gap-state pinning impede device functionality.

Purpose of the Study:

• To present semiconducting Platinum Diselenide (PtSe2) field-effect transistors with all-van-der-Waals interfaces.
• To demonstrate a solution for contact resistance in 2D materials.

Main Methods:

• Fabrication of PtSe2 field-effect transistors using graphite electrodes.
• Characterization of device performance, including on/off ratios, current, mobility, stability, and contact resistance.

Main Results:

• Achieved high on/off ratios (up to 10^9) and currents (>100 microA/microm).
• Demonstrated high mobilities (50 cm^2/Vs at room temp, >400 cm^2/Vs at 10K).
• Exhibited excellent device stability (hysteresis < 36 mV nm^-1) and low contact resistance (< 700 Ohm*microm).

Conclusions:

• PtSe2 with graphite contacts offers a promising pathway for high-performance 2D circuits.
• This integrated approach addresses critical contact resistance issues in 2D electronics.
• The developed devices show potential for future all-2D electronic applications.