定义具有可逆压响应的铁电特征:PUND切换光谱 PFM特性表征
Denis Alikin1, Violetta Safina1, Alexander Abramov1
1School of Natural Sciences and Mathematics, Ural Federal University, Ekaterinburg, Russia.
Nanotechnology
|January 5, 2024
概括
在纳米尺度上检测铁电是非常重要的. 一种新的方法,正上负下 (PUND) 切换光谱学和压响应力显微镜 (SSPFM),克服了自发逆转和静电力方面的问题,以准确地表征材料.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 凝聚物质物理学 凝聚物质物理学
背景情况:
- 在微和纳米尺度上检测铁电对于开发先进的纳米材料至关重要.
- 切换光谱 压响应力显微镜 (SSPFM) 是一种用于局部铁电特征的标准技术.
- 诸如静电力和电流流等寄生因素往往导致SSPFM中不可预测的hysteresis循环形状.
研究的目的:
- 调查SSPFM中不可预测的歇斯底里循环形状的原因.
- 开发一种改进的SSPFM方法,用于准确的铁电特性.
- 将SSPFM的适用性扩展到更广泛的铁电材料.
主要方法:
- 作为扭曲的歇斯底里循环的原因,研究了自发的逆转.
- 分析了SSPFM波形参数 (持续时间,频率,交流电压幅度) 的影响.
- 在"步骤模式"中使用正上负下 (PUND) 方法开发了修改后的SSPFM方法.
主要成果:
- 鉴定出极化逆转后自发的逆转为影响歇斯底里循环形状的关键因素.
- 证明不适当的SSPFM波形参数会加剧自发的反向开关.
- "步骤模式"SSPFM中的PUND方法有效地消除了静电贡献,并探测了真正的压电歇斯底里循环.
结论:
- 重新设计的SSPFM方法与"步骤模式"中的PUND提供可靠的局部压电歇斯底里循环测量.
- 这一进步提高了铁电性质的表征,特别是在半导体铁电和放松器中.
- 这种新方法为纳米级铁电检测提供了一个更准确,更通用的工具.
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