Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle (Saale), Germany.
ACS Nano. 2011 Jul 26;5(7):6032-8. doi: 10.1021/nn2018528. Epub 2011 Jun 23.
Spontaneous polarization of ferroelectric materials has been for a long time proposed as binary information support, but it suffers so far from destructive readout. A nondestructive resistive readout of the ferroelectric polarization state in a metal-ferroelectric-metal capacitor would thus be advantageous for data storage applications. Combing conducting force microscopy and piezoelectric force microscopy, we unambiguously show that ferroelectric polarization direction and resistance state are correlated for epitaxial ferroelectric Pb(Zr(0.2)Ti(0.8))O(3) nanoscale capacitors prepared by self-assembly methods. For intermediate ferroelectric layer thickness (∼9 nm) sandwiched between copper and La(0.7)Sr(0.3)MnO(3) electrodes we achieved giant electroresistance with a resistance ratio of >1500 and high switching current densities (>10 A/cm(2)) necessary for effective resistive readout. The present approach uses metal-ferroelectric-metal devices at room temperature and, therefore, significantly advances the use of ferroelectric-based resistive switching.
铁电材料的自发极化长期以来被提议作为二进制信息支持,但迄今为止,它受到破坏性读出的困扰。因此,在金属-铁电体-金属电容器中对铁电极化状态进行非破坏性电阻读出对于数据存储应用是有利的。结合导电力显微镜和压电力显微镜,我们明确地表明,对于通过自组装方法制备的外延铁电 Pb(Zr(0.2)Ti(0.8))O(3)纳米级电容器,铁电极化方向和电阻状态是相关的。对于夹在铜和 La(0.7)Sr(0.3)MnO(3)电极之间的中间铁电层厚度(约 9nm),我们实现了具有>1500 的大电阻比和有效电阻读出所需的高开关电流密度(>10A/cm(2))的巨大电电阻。本方法在室温下使用金属-铁电体-金属器件,因此显著推进了基于铁电体的电阻开关的应用。