Enhanced polarization switching and superior endurance in (Hf_0.5Zr_0.5O₂-ZrO₂)_n nanolaminates via interface engineering

Hafnia-based ferroelectric/antiferroelectric (FE/AFE) nanolaminates offer exceptional scalability and complementary-metal-oxide-semiconductor compatibility, making them promising candidates for high-density and low-power memories. However, the deliberate design of periodic interfaces to tailor their ferroelectric performance remains underexplored. Herein, (Hf_0.5Zr_0.5O₂-ZrO₂)_n ((HZO-ZrO₂)_n) nanolaminates with different interface numbers (n = 1, 2, 4, 6) are systematically investigated to unveil its impact on polarization, switching dynamics, and device reliability. The (HZO-ZrO₂)₂ configuration achieves an optimal comprehensive performance, exhibiting a large remnant polarization (25.41 μC/cm²), ultrafast switching speed (0.21 μs at 4.8 V), excellent endurance (negligible polarization degradation after 10⁸ cycles), and high 10-year retention capability (97.4%). Moreover, the heterogeneous interface between ZrO₂ and Hf_0.5Zr_0.5O₂ can effectively modulate the distribution of oxygen vacancies and polarization-switching barriers. Beyond an optimal number, however, additional interfaces can largely increase the coercive field and hinder domain reversal. These findings provide a powerful design principle for realizing reliable and high-performance hafnia-based ferroelectric memories through interface engineering.