HfO2 nanodots and epitaxial HfO2 thin films with ferroelectric properties were grown on yttria-stabilized zirconia substrates with indium tin oxide bottom electrodes via a pulsed laser deposition (PLD) method. The crystallinity and ferroelectric properties of the epitaxial HfO2 thin films were analyzed to compare ferroelectric properties resulting from crystallinity and the strained structure of HfO2 nanodots. Using the total number of PLD pulses as a control, it was possible to grow HfO2 nanodots with diameters of 7, 12, and 20 nm and heights of 4.9, 7.8, and 14.8 nm. Based on the d33 piezoelectric hysteresis loops and polarization switching phenomena, it was confirmed that the HfO2 nanodots exhibited good ferroelectric properties even for scaling of less than 7 nm in diameter. The observation of the piezoelectric d33 hysteresis loop of the HfO2 nanodots and epitaxial HfO2 thin films revealed that HfO2 nanodots had improved ferroelectric properties due to the size effect.

中文翻译：

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沉积在 ITO 底部电极上的直径小于 10 nm 的 HfO2 纳米点的铁电特性

HfO2 纳米点和具有铁电特性的外延 HfO2 薄膜通过脉冲激光沉积 (PLD) 方法在具有氧化铟锡底部电极的氧化钇稳定的氧化锆衬底上生长。分析了外延 HfO2 薄膜的结晶度和铁电特性，以比较由结晶度和 HfO2 纳米点的应变结构引起的铁电特性。使用 PLD 脉冲总数作为对照，可以生长直径为 7、12 和 20 纳米、高度为 4.9、7.8 和 14.8 纳米的 HfO2 纳米点。基于 d33 压电磁滞回线和极化切换现象，证实 HfO2 纳米点即使在直径小于 7 nm 的缩放时也表现出良好的铁电性能。