Polarity Engineering in a Single MoTe₂ Device for Homogeneous Complementary Circuit Applications.

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Two-dimensional (2D) materials offer unique electronic properties due to their atomic thinness.
• Precise control over n-type and p-type conductivity in a single 2D material is crucial for complementary circuits but remains challenging.

Purpose of the Study:

• To develop a versatile polarity engineering strategy for Molybdenum Ditelluride (MoTe2).
• To demonstrate the fabrication of both n-type and p-type field-effect transistors (FETs) on a single MoTe2 flake.
• To explore the potential for integrated complementary circuits and reversible polarity switching.

Main Methods:

• Utilized poly(methyl methacrylate) (PMMA)-assisted molecular adsorption for p-type doping of MoTe2.
• Employed focused electron beam irradiation for n-type doping of MoTe2.
• Fabricated and characterized MoTe2 p-FETs and n-FETs on a single flake.

Main Results:

• Achieved high ON-currents (>2 μA at 1 V), low subthreshold swings (<451.3 mV/dec), and high ON/OFF ratios (>10^4) for both polarities.
• Demonstrated functional complementary circuits including inverters (gain ~48), NAND/NOR gates, and full-wave rectifiers.
• Showcased reversible polarity conversion in a single MoTe2 device through controlled doping.

Conclusions:

• The developed polarity engineering strategy is effective for creating high-performance MoTe2-based electronic devices.
• This approach facilitates the integration of 2D materials into complex complementary circuits.
• The ability to switch polarity reversibly opens new avenues for reconfigurable and versatile 2D semiconductor devices.