The scale-free ferroelectricity with superior Si compatibility of HfO₂ has reawakened the feasibility of scaled-down nonvolatile devices and beyond the complementary metal–oxide–semiconductor (CMOS) architecture based on ferroelectric materials. However, despite the rapid development, fundamental understanding, and control of the metastable ferroelectric phase in terms of oxygen ion movement of HfO₂ remain ambiguous. In this study, we have deterministically controlled the orientation of a single-crystalline ferroelectric phase HfO₂ thin film via oxygen ion movement. We induced a topotactic phase transition of the metal electrode accompanied by the stabilization of the differently oriented ferroelectric phase HfO₂ through the migration of oxygen ions between the oxygen-reactive metal electrode and the HfO₂ layer. By stabilizing different polarization directions of HfO₂ through oxygen ion migration, we can gain a profound understanding of the oxygen ion-relevant unclear phenomena of ferroelectric HfO₂.

中文翻译：

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通过氧化物电极的拓扑相变控制铁电 HfO2 薄膜生长的确定性取向


HfO ₂ 的无标度铁电性与优异的硅兼容性重新唤醒了小型化非易失性器件的可行性，超越了基于铁电材料的互补金属氧化物半导体 (CMOS) 架构。然而，尽管发展迅速，但对 HfO ₂ 氧离子运动的亚稳态铁电相的基本理解和控制仍然不明确。在这项研究中，我们通过氧离子运动确定性地控制了单晶铁电相 HfO ₂ 薄膜的取向。通过氧离子在氧反应金属电极和 HfO ₂ 的稳定。 > 层。通过氧离子迁移稳定HfO ₂ 的不同极化方向，我们可以深刻理解铁电HfO ₂ 与氧离子相关的不清楚现象。