在HfO2膜中揭示铁电疲劳路径
Yufeng Xue1, Qi Hu1, Zhongfei Xu2
1School of Physics, Beihang University, Beijing, 100191, China.
Small methods
|June 16, 2025
概括
氧化 (HfO2) 铁电疲劳是由直接相位过渡引起的,而不是多个路径. 应用在平面上的应变可以抑制这种疲劳,提高内存设备的可靠性.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 计算材料科学科学 计算材料科学
背景情况:
- 氧化 (HfO2) 在超薄膜中表现出铁电性,这对于下一代非易失性记忆至关重要.
- 极化疲劳和脱极化现象阻碍了HfO2的实际应用,这些应用源于复杂的铁电-电过渡.
研究的目的:
- 系统地探索HfO2中所有潜在的相位过渡路径,从铁电到电状态.
- 阐明HfO2薄膜中铁电疲劳背后的机制.
主要方法:
- 对称性分析与第一原则计算相结合.
- 调查各种过渡途径的能源障碍,包括直接和多步过渡.
主要成果:
- 涉及中间阶段的多个过渡途径需要高能障碍 (0.330.71 eV/单元电池).
- 从铁电OIII阶段直接过渡到电MI阶段的直接过渡具有显著较低的能量屏障 (0.11 eV/单元电池).
- 这种直接过渡涉及大约4%的平面内膨胀.
结论:
- 在HfO2中铁电疲劳主要是由直接过渡路径驱动的.
- 应用飞机内限制或压力应变可以通过阻碍这种直接过渡来有效地抑制疲劳.
- 研究结果为优化HfO2在先进的记忆技术中提供了关键的见解.
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