Synergistic Modulation of Polarization and Leakage Current in MPB‐HZO Capacitors via TiO ₂ Interlayer

Abstract To address critical reliability concerns in ferroelectric devices, the role of a TiO 2 interlayer in modulating the electrical characteristics of Hf x Zr 1‐x O 2 (HZO)‐based metal‐ferroelectric‐metal (MFM) capacitors near the morphotropic phase boundary (MPB) is investigated. The TiO 2 interlayer is inserted at the HZO interface to selectively modulate defect behavior while preserving the desired MPB phase composition. Electrical, structural, and spectroscopic analyses reveal that TiO 2 integration enables 1) suppression of leakage pathways, 2) stabilization of polarization with enhanced dielectric response, 3) modulation of oxygen vacancy (V O ) distribution, and 4) reduction of low‐frequency noise (LFN) amplitude. These synergistic effects collectively improve the reliability and energy efficiency of MPB‐HZO capacitors, offering a promising interface‐engineering strategy for next‐generation ferroelectric DRAM technologies.