Gate-Coupling-Enabled Robust Hysteresis for Nonvolatile Memory and Programmable Rectifier in Van der Waals...

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Ferroelectric field-effect transistors (FeFETs) typically face challenges with interface quality.
• Two-dimensional (2D) layered ferroelectric materials offer potential for high-quality, thin FeFETs via van der Waals heterostructures (vdWHs).

Purpose of the Study:

• To construct and characterize dual-gated 2D ferroelectric vdWHs for advanced electronic applications.
• To investigate the role of hexagonal boron nitride (h-BN) and dual-gating in stabilizing ferroelectric CuInP2S6 (CIPS).

Main Methods:

• Fabrication of dual-gated vdWHs using MoS2, h-BN, and CIPS.
• Electrical characterization of the vdWHs as nonvolatile memory and programmable rectifiers.

Main Results:

• The device demonstrated record performance as nonvolatile memory: large memory window, high on/off ratio (10^7), ultralow programming current (10^-13 A), and excellent endurance.
• As a programmable rectifier, the device exhibited gate-tunable behavior and a large rectification ratio (3 × 10^5) with stable retention.

Conclusions:

• The integration of h-BN and dual-gating effectively stabilizes and polarizes ferroelectric CIPS.
• These engineered ferroelectric vdWHs show significant promise for developing next-generation multifunctional electronic devices.