Nonvolatile Sequential Logic Enabled by CuInP₂S₆ van der Waals Ferroelectric Field-Effect Transistors

Area of Science:

• Materials Science
• Solid State Physics
• Computer Engineering

Background:

• Nonvolatile flip-flops and latches are crucial for reliable, energy-efficient computing, especially with intermittent power.
• Ferroelectric field-effect transistors (FeFETs) using van der Waals (vdW) heterostructures offer a path to integrate memory into logic, reducing degradation.

Purpose of the Study:

• To fabricate and characterize CuInP2S6-based vdW FeFETs.
• To demonstrate a nonvolatile ferroelectric latch for reliable state restoration after power loss.
• To establish a platform for nonvolatile sequential logic and energy-efficient computing.

Main Methods:

• Fabrication of CuInP2S6 vdW FeFETs in MFIMS and MFS configurations.
• Realization of ferroelectric nonvolatile inverters and a nonvolatile ferroelectric latch.
• Utilizing ambipolar MoTe2 channels for inherent rail-to-rail voltage driving in the latch design.

Main Results:

• Demonstrated robust ferroelectric switching and stable nonvolatile behavior in the fabricated FeFETs.
• Successfully realized a nonvolatile ferroelectric latch that reliably restores its logic state post-power loss.
• The latch achieved state restoration using simple control signals due to intrinsic circuit operation and clean vdW interfaces.

Conclusions:

• 2D vdW FeFETs show strong performance for nonvolatile applications.
• The demonstrated nonvolatile latch is a viable platform for nonvolatile sequential logic.
• This work advances energy-efficient computing architectures through integrated nonvolatile memory and logic.