We report the experimental realization of ferroelectricity in Al-doped HfO₂ (HAO) with the lowest reported thermal budget of 500 °C. A HAO film annealed at 500 °C for 30 s exhibits ferroelectricity with a remnant polarization ( ${P}_{{\text {r}}}$ ) of $2.95~\mu \text{C}$ /cm². The ${P}_{{\text {r}}}$ increases to $10.40~\mu \text{C}$ /cm² when annealing duration is increased to 5 min, and approaches the values annealed at much higher temperatures of 700 to 1000 °C in other previous works. The presence of ferroelectricity has been confirmed by a series of typical phenomena, including the polarization-switched Positive-Up-Negative-Down measurement, the hysteretic polarization-voltage loop, and the butterfly-shaped C-V curves. In addition, comparable endurance characteristics are also obtained with other HfO₂-based ferroelectric films.

中文翻译：

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在 500 °C 的低热预算下证明掺铝 HfO2 中的铁电性

我们报告了铁电性在 Al 掺杂的 HfO ₂ (HAO) 中的实验实现，其报告的最低热预算为 500 °C。在 500 °C 下退火 30 s 的 HAO 薄膜表现出具有剩余极化的铁电性（ ${P}_{{\text {r}}}$ ） 的 $2.95~\mu \text{C}$ /厘米²。这 ${P}_{{\text {r}}}$ 增加到 $10.40~\mu\text{C}$ /cm ²当退火持续时间增加到 5 分钟时，接近在其他先前工作中在 700 至 1000 °C 的更高温度下退火的值。铁电性的存在已被一系列典型现象所证实，包括极化切换的正上负下测量、磁滞极化电压回路和蝴蝶形简历曲线。此外，其他基于HfO ₂的铁电薄膜也获得了类似的耐久性特性。