Selective Polarity Control of Metal Oxide Semiconductors for Complementary Logic Gates

Area of Science:

• Materials Science
• Semiconductor Physics
• Electronics Engineering

Background:

• Tunable charge carrier polarity is crucial for programmable complementary logic circuits.
• Existing methods using 2D semiconductors face scalability and integration challenges due to interfacial sensitivity.

Purpose of the Study:

• To present a robust polarity-conversion strategy for tin oxide (SnO) semiconductors.
• To demonstrate the feasibility of electrolyte-gated transistors (EGTs) for achieving polarity control.
• To enable the monolithic integration of complementary logic gates on a single SnO layer.

Main Methods:

• Utilized electrolyte-gated transistors (EGTs) with tin oxide (SnO) as the semiconductor material.
• Employed in situ electrochemical doping to convert p-type SnO to n-type SnO₂ via Sn²⁺ to Sn⁴⁺ oxidation.
• Demonstrated spatially selective electrochemical doping for integrated circuit fabrication.

Main Results:

• Achieved p-type and n-type EGTs with excellent electrical characteristics: low-voltage operation, high ON/OFF current ratios, sharp switching, and long-term stability.
• Successfully fabricated integrated complementary logic gates (inverter, NAND, NOR) on a single SnO layer.
• Validated a scalable and versatile polarity-conversion strategy for oxide-based electronics.

Conclusions:

• Electrochemical doping in SnO EGTs offers a robust solution for tunable charge carrier polarity.
• This approach overcomes the limitations of 2D semiconductors for logic circuit applications.
• The developed strategy paves the way for scalable, oxide-based programmable complementary circuits.