The Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
ACS Nano. 2012 Jan 24;6(1):491-500. doi: 10.1021/nn203831h. Epub 2011 Dec 9.
Spatially resolved polarization switching in ferroelectric nanocapacitors was studied on the sub-25 nm scale using the first-order reversal curve (FORC) method. The chosen capacitor geometry allows both high-veracity observation of the domain structure and mapping of polarization switching in a uniform field, synergistically combining microstructural observations and probing of uniform-field polarization responses as relevant to device operation. A classical Kolmogorov-Avrami-Ishibashi model has been adapted to the voltage domain, and the individual switching dynamics of the FORC response curves are well approximated by the adapted model. The comparison with microstructures suggests a strong spatial variability of the switching dynamics inside the nanocapacitors.
利用一阶反转曲线 (FORC) 方法，在亚 25nm 尺度上研究了铁电纳米电容器中的空间分辨极化反转。选择的电容器几何形状允许对畴结构进行高精度观察，并在均匀场中对极化反转进行映射，协同结合了与器件操作相关的微观结构观察和对均匀场极化响应的探测。已将经典的 Kolmogorov-Avrami-Ishibashi 模型应用于电压域，并且 FORC 响应曲线的各个开关动力学都可以很好地用所适应的模型来近似。与微结构的比较表明，纳米电容器内部的开关动力学具有很强的空间变异性。
