Facet-Engineered Atomic Interface and On-Chip Continuous-Amplitude Modulated Recovery Enabling Ultra-High Endurance for Hafnium-Based Ferroelectric Memories.

Abstract

Ferroelectric hafnia-based materials have made considerable progress toward ultradense nonvolatile memories and beyond-Moore devices. While doping, intercalation, and strain engineering have successfully stabilized the metastable orthorhombic phase─essential for ferroelectricity, device resilience against fatigue under repeated electric field cycling remains a critical challenge. The fatigue is primarily attributed to issues related to continuous interfacial charge injection, oxygen vacancy formation and aggregation, and subsequent polarization pinning and phase degradation. Here, we propose a comprehensive solution to mitigate fatigue in Hf_0.5Zr_0.5O₂ memory arrays by combining facet-engineered TiN electrodes and well-coordinated on-chip continuous-amplitude modulated recovery (CAMR) designs. The deliberate controlling of TiN nanocolumn morphology with preferential {111} facet orientation and matched surface oxidation can inhibit interfacial charge injection, polarization pinning, and irreversible phase change fatigue due to elevated interfacial barrier, more orderly interface electrostatic environment, and enhanced tandem restriction of out-of-plane volume expansion. Leveraging these stable atomic interfacial states in conjunction with the CAMR circuit for efficient oxygen vacancy redistribution, the ferroelectric capacitors exhibit excellent intrinsic residual polarization (2<i>P</i>_r = 52 μC/cm²), negligible wake-up effects, and ultra-high endurance exceeding 10¹³ cycles, maintaining excellent sustainability. The synergistic design provides a valid pathway for the integration and large-scale applications of hafnium-based ferroelectric nonvolatile memories.