Ultra-high Tunneling Electroresistance Ratio (2 × 104) & Endurance (108) in Oxide Semiconductor-Hafnia Self-rectifying (1.5 × 103) Ferroelectric Tunnel Junction

Abstract

In this study, we present a remarkable improvement in the performance of hafnia-based ferroelectric tunnel junctions (FTJs) using oxygen scavenging technology and extremely low-damage (ELD) deposition, leading to a significant increase in the tunneling electroresistance ratio $({\mathrm {TER}}) (\gt 2 \times 10^{4})$, on-current density $(\gt 10^{-2}\mathrm{A} /cm^{2})$, and self-rectifying ratio $({\mathrm {RR}}) (\gt 1.5 \times 10^{3})$. First-principles DFT simulations were also used to evaluate how the asymmetric oxygen vacancy (VO) distribution affected FTJs. As an array-level demonstration of the proposed approach, we experimentally built an FTJ-based XNOR synapse array and verified its operation for binary neural networks (BNN).