Gate-Tunable and Multidirection-Switchable Memristive Phenomena in a Van Der Waals Ferroelectric

Area of Science:

• Materials Science
• Solid State Physics
• Nanotechnology

Background:

• Memristive devices are crucial for nonvolatile memory, logic circuits, and artificial synapses.
• Optimizing memristor performance requires precise control over conducting paths and resistance switching.
• Hexagonal α-In₂Se₃ is a semiconducting van der Waals ferroelectric material with potential for advanced electronic applications.

Purpose of the Study:

• To demonstrate gate tunability and multidirectional switching in memristors using hexagonal α-In₂Se₃.
• To modulate conducting paths for enhanced memristor performance, including ON/OFF ratios.
• To explore the potential of ferroelectric α-In₂Se₃ memristors for logic circuits and neuromorphic computing.

Main Methods:

• Fabrication and characterization of planar memristors utilizing in-plane (IP) polarization of α-In₂Se₃.
• Integration and testing of vertical α-In₂Se₃ memristors based on out-of-plane (OOP) polarization.
• Development and evaluation of a multidirectionally operated α-In₂Se₃ memristor.

Main Results:

• Planar α-In₂Se₃ memristors exhibited switchable photocurrent, gate-tunable channel conductance, ferroelectric polarization, and resistance-switching ratio.
• Vertical α-In₂Se₃ memristors achieved high device density (7.1 × 10⁹ in.⁻²) and a resistance-switching ratio exceeding 10³.
• A novel multidirectional α-In₂Se₃ memristor allowed direct control of OOP (or IP) resistance states via IP (or OOP) pulses, a capability not seen in other memristors.

Conclusions:

• Ferroelectric hexagonal α-In₂Se₃ is a promising material for developing advanced memristive devices.
• The demonstrated gate tunability and multidirectional switching offer new pathways for device optimization.
• These α-In₂Se₃ memristors show significant potential for future logic circuits and complex neuromorphic computing systems.