Area-Selective Chemical Doping on Solution-Processed MoS₂ Thin-Film for Multi-Valued Logic Gates

Area of Science:

• Materials Science
• Nanoscience
• Electronics Engineering

Background:

• Molybdenum disulfide (MoS2) is a promising 2D material for advanced electronic applications.
• Developing multi-valued logic gates is crucial for enhancing computational efficiency.
• Existing fabrication methods for MoS2 transistors often lack pathways for complex logic operations.

Purpose of the Study:

• To demonstrate multi-valued logic gates using solution-processed molybdenum disulfide (MoS2) thin films.
• To introduce a chemical doping process for MoS2 to create pseudo-heterojunctions.
• To explore the potential of these devices for ternary logic operations.

Main Methods:

• Solution-processed MoS2 thin films were fabricated.
• A chemical doping process was applied to locally increase the work function of MoS2 by reducing sulfur vacancies.
• Pseudo-heterojunctions were formed between as-processed MoS2 and chemically treated MoS2 (c-MoS2).
• Device geometries (channel thickness and length) were modulated to tune performance.

Main Results:

• The energy-band misalignment between MoS2 and c-MoS2 enabled sequential channel activation.
• A stable intermediate state for ternary operation was achieved.
• Ternary logic gates, including inverter, NMIN, and NMAX, were successfully demonstrated.
• Device performance was tunable via geometric modifications.

Conclusions:

• Chemically doped MoS2 thin films can effectively implement multi-valued logic gates.
• The developed pseudo-heterojunction approach offers a viable route for ternary logic.
• This work advances the development of next-generation electronic devices based on 2D materials.