Enhancement of Ferroelectricity in Hf 0.5 Zr 0.5 O 2 via Pre-Crystallization and Interface Engineering at Ultra-Low Temperature (300 °C) Annealing

作者：Keyou Tong, Jing Xu, Bohan Chen, Xu Chen, Binbin Xu, Shuai Yang, Xiaolei Wang, Jun Luo · 发表于：IEEE Electron Device Letters · 年份：2025 · DOI：10.1109/led.2025.3563376 · 被引用次数：3 · 研究领域：Ferroelectric and Negative Capacitance Devices、Semiconductor materials and devices、MXene and MAX Phase Materials

The interface degradation between ferroelectric film and surrounding layers limits the endurance of hafnia ferroelectric devices significantly. This letter proposes a promising TiN/TZHZT/TiN structure with TiO2/ZrO2bi-interlayers on both sides of a sub-7 nm Hf0.5Zr0.5O2(HZO). The TZHZT sample underwent ultra-low temperature annealing at 300 °C demonstrates exceptional ferroelectric properties,i.e.significant remnant polarization (2Pr=28.2 μC/cm2), appropriate coercive field (Ec=1.7 MV/cm), and excellent endurance exceeding 1010cycles. Achieved results are attributed to the synergistic effects of dual interlayer engineering. Specifically, the ZrO2interlayer promotes the growth of ferroelectric grains through the formation of seed crystals, leading to larger grain size after annealing. Meanwhile, the TiO2interlayer enhances tensile stress and oxygen enrichment, thereby improving both 2Prand endurance. Moreover, the ZrO2interlayer effectively compensates the deficiency of breakdown strength for TiO2layer.