Gate-tunable memristive phenomena mediated by grain boundaries in single-layer MoS2

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology
• Electrical Engineering

Background:

• High-speed computing requires advancements in materials and device architectures.
• Memristors offer potential for enhanced logic and memory performance.
• Current metal-insulator-metal (MIM) memristors face limitations in filament control and switching voltage regulation.

Purpose of the Study:

• To introduce a new class of memristors utilizing grain boundaries (GBs) in single-layer molybdenum disulfide (MoS₂).
• To investigate the modulation of resistance at GBs for improved memristive device functionality.
• To explore the potential for gate-controlled voltage tuning in MoS₂-based memristors.

Main Methods:

• Fabrication of memristive devices based on single-layer MoS₂.
• Characterization of resistance modulation at grain boundaries (GBs) connected to contacts.
• Investigation of switching ratios and dynamic negative differential resistance (NDR).
• Utilizing a third gate terminal for field-effect geometry tuning of the set voltage.

Main Results:

• Demonstrated easily and repeatedly modulated resistance at MoS₂ grain boundaries.
• Achieved high switching ratios of up to approximately 10^3.
• Observed dynamic negative differential resistance (NDR) in the devices.
• Showcased gate-tunable set voltage, enabling new functionalities.

Conclusions:

• Grain boundaries in single-layer MoS₂ provide a viable platform for novel memristor development.
• These MoS₂-based memristors exhibit superior switching characteristics and external control capabilities.
• The atomically thin nature and gate-tunability offer unique advantages over conventional memristive devices for future electronics.