Changes in the interface capacitance for fatigued lead–zirconate–titanate capacitors
Changes in the interface capacitance for fatigued lead–zirconate–titanate capacitors
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DOI：
10.1063/1.1367301
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发表时间：
2001-04
影响因子：
4
通讯作者：
X. Meng;J. L. Sun;J. Yu;L. Bo;Chu-Wei Jiang;Quan Sun;S. Guo;J. Chu
中科院分区：
文献类型：
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作者：
X. Meng;J. L. Sun;J. Yu;L. Bo;Chu-Wei Jiang;Quan Sun;S. Guo;J. Chu
从Pt/PbZr0.5Ti0.5O3/Pt电容器的电容电压依赖性出发，通过数学方法将电容分为两部分，分别对应样品的均匀电场区和非均匀电场区。它们分别与体铁电膜区和Pt/PbZr0.5Ti0.5O3肖特基势垒界面区相关。基于串联电容模型的计算表明，疲劳体膜的介电常数略有下降。假设界面区的介电常数比块体膜的介电常数小得多，发现疲劳后界面电容比块体铁电膜明显减小。这主要归因于界面层铁电性的降低，表明疲劳主要是一个界面状态控制的过程。界面电容-电压曲线的不对称性是由于缺陷浓度不同造成的。
From the capacitance–voltage dependence of Pt/PbZr0.5Ti0.5O3/Pt capacitors, we mathematically separated the capacitance into two parts corresponding to two regions of the samples, the uniform electric-field region and the nonuniform region. They are correlated with the bulk ferroelectric film region and the Pt/PbZr0.5Ti0.5O3 Schottky barrier interface region, respectively. The calculations based on the in-series capacitor model show a slight decrease of dielectric permitivity for the fatigued bulk films. By assuming a much smaller dielectric permitivity of the interface region than that of bulk films, it was found that the interface capacitance decreased remarkably compared with that of the bulk ferroelectric film after fatigue. This decrease was attributed to the lowering of ferroelectricity in the interface layer, which suggests that the fatigue is mainly an interface state controlled process. The asymmetricity in the interface capacitance–voltage curve is attributed to the different defect concentratio...