Intrinsic Nonlinearity Modulation in Two-Dimensional (Cu,Ag)InP₂S₆ for Selectorless Nonvolatile Memory Array.

Area of Science:

• Materials Science
• Solid-State Electronics
• Nanotechnology

Background:

• Selectorless resistive random-access memory (RRAM) is crucial for high-density crossbar arrays.
• Suppressing sneak path currents (SPCs) without external selectors is a significant challenge.

Purpose of the Study:

• To investigate Cu$_{0.5}$Ag$_{0.5}$InP$_{2}$S$_{6}$ (CAIPS) as a switching layer for selectorless RRAM.
• To compare the resistive switching properties of CAIPS with CuInP$_{2}$S$_{6}$ (CIPS) and AgInP$_{2}$S$_{6}$ (AIPS).

Main Methods:

• Fabrication and characterization of CAIPS, CIPS, and AIPS based devices.
• First-principles density functional theory (DFT) calculations to understand diffusion barriers.
• Systematic comparison of resistive switching performance, including nonlinearity and memory window.

Main Results:

• CAIPS exhibits self-rectifying transport and intrinsic SPC suppression due to asymmetric ion diffusion.
• CAIPS devices show stable bipolar switching, high nonlinearity (>10), large memory window (>9x), and low variability (CV=5.1%).
• Performance of CAIPS surpasses that of CIPS and AIPS.

Conclusions:

• CAIPS is a promising material for scalable selectorless memory arrays.
• Its built-in nonlinearity and excellent switching characteristics are relevant for neuromorphic and edge computing.
• CAIPS offers a pathway to energy-efficient, high-density memory solutions.