Polarity control of 2D semiconductor for reconfigurable electronics

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Controllable carrier polarity modulation is crucial for reconfigurable electronic devices.
• Ambipolar two-dimensional (2D) semiconductors offer excellent gate modulation but lack reversible polarity control methods.
• Existing polarity control techniques face challenges in achieving reversible modulation during device operation.

Purpose of the Study:

• To introduce a novel strategy for reversibly modulating the polarity of ambipolar 2D semiconductors.
• To demonstrate the feasibility of gate-controlled charge trapping for polarity switching.
• To explore the application of this method in advanced electronic devices.

Main Methods:

• Fabrication of a double-gate TaO_x/WSe₂/h-BN field-effect transistor.
• Utilizing electric-field-driven bipolar charge trapping at the TaO_x/WSe₂ interface for polarity modulation.
• Characterization of the transistor's switching behavior between n-type and p-type transport.

Main Results:

• Demonstrated reversible switching between n-type and p-type transport characteristics in a single WSe₂ flake.
• Achieved an electrically configurable complementary inverter with ultra-low power consumption (0.7 nW).
• Realized a programmable p-n/n-p diode with a significant change (>100,000-fold) in rectification ratio.

Conclusions:

• Gate-controlled bipolar charge trapping offers a viable route for reversible polarity modulation in ambipolar 2D semiconductors.
• This technique paves the way for highly efficient and reconfigurable electronic devices.
• The demonstrated devices highlight the potential for advancing next-generation electronics.