Phase field modeling of domain dynamics and polarization accumulation in ferroelectric HZO
Phase field modeling of domain dynamics and polarization accumulation in ferroelectric HZO
复制标题
DOI：
10.1063/1.5092707
复制
发表时间：
2019-01
影响因子：
4
通讯作者：
A. Saha;K. Ni;S. Dutta;S. Datta;S. Gupta
中科院分区：
文献类型：
--
作者：
A. Saha;K. Ni;S. Dutta;S. Datta;S. Gupta
本文研究了铁电薄膜在连续亚矫顽场脉冲作用下的累积极化反转特性。通过对Hf0.4Zr0.6O2（HZO）晶体的动态相场模拟（基于含时Landau-Ginzburg模型）和实验测量，分析了电场诱导畴壁运动及其导致的P在铁电晶体中的积累过程。根据我们的分析，即使在没有外加电场的情况下，DW也可能发生自发运动。这种DW不稳定性导致自发的P-激发和弛豫过程，这在FE晶粒中的累积P-开关中起关键作用。我们表明，这种P积累的程度增加，在所施加的电场，激发时间的增加和弛豫时间的减少。最后，通过考虑具有局部和全局矫顽场分布的晶粒系综，我们模拟了大面积HZO样品中的P积累过程。在这样的多晶粒的情况下，P积累对所施加的电场脉冲属性的依赖性遵循类似的功能，作为一个单一的晶粒，虽然自发过程（激发/弛豫）是不太突出的大面积sample.In这项工作中，我们研究了铁电（FE）薄膜的累积极化（P）开关特性的影响下，顺序的亚矫顽电场脉冲。通过对Hf0.4Zr0.6O2（HZO）晶体的动态相场模拟（基于含时Landau-Ginzburg模型）和实验测量，分析了电场诱导畴壁运动及其导致的P在铁电晶体中的积累过程。根据我们的分析，即使在没有外加电场的情况下，DW也可能发生自发运动。这种DW不稳定性导致自发的P-激发和弛豫过程，这在FE晶粒中的累积P-开关中起关键作用。我们表明，这种P积累的程度增加，在所施加的电场，激发时间的增加和弛豫时间的减少。最后，通过考虑本地和全球矫顽场分布的晶粒系综，我们模型的P-积累…
In this work, we investigate the accumulative polarization (P) switching characteristics in ferroelectric (FE) thin films under the influence of sequential sub-coercive electric-field pulses. Performing the dynamic phase-field simulation (based on time-dependent Landau-Ginzburg model) and experimental measurement on Hf0.4Zr0.6O2 (HZO), we analyze the electric field induced domain-wall (DW) motion and the resultant P accumulation process in FE. According to our analysis, even in the absence of an applied electric field, the DW can potentially undergo spontaneous motion. Such a DW instability leads to spontaneous P-excitation and relaxation processes, which play a pivotal role in accumulative P-switching in an FE grain. We show that the extent of such P accumulation increases with the increase in the applied electric field, increase in excitation time and decrease in relaxation time. Finally, by considering an ensemble of grains with local and global coercive field distributions, we model the P-accumulation process in a large area HZO sample. In such a multi-grain scenario, the dependency of P accumulation on the applied electric field pulse attributes follows similar features as that of a single-grain, although the spontaneous processes (excitation/relaxation) are less prominent in large area sample.In this work, we investigate the accumulative polarization (P) switching characteristics in ferroelectric (FE) thin films under the influence of sequential sub-coercive electric-field pulses. Performing the dynamic phase-field simulation (based on time-dependent Landau-Ginzburg model) and experimental measurement on Hf0.4Zr0.6O2 (HZO), we analyze the electric field induced domain-wall (DW) motion and the resultant P accumulation process in FE. According to our analysis, even in the absence of an applied electric field, the DW can potentially undergo spontaneous motion. Such a DW instability leads to spontaneous P-excitation and relaxation processes, which play a pivotal role in accumulative P-switching in an FE grain. We show that the extent of such P accumulation increases with the increase in the applied electric field, increase in excitation time and decrease in relaxation time. Finally, by considering an ensemble of grains with local and global coercive field distributions, we model the P-accumulation...