Interfaces in nanosize perovskite titanate ferroelectrics — microstructure and impact on selected properties

Abstract

Interfaces in nanosize perovskite titanate ferroelectrics -microstructure and impact on selected propertiesMisfit dislocations in epitaxial Pb(Zr 0.52 Ti 0.48 )O 3 (PZT) nanoislands on SrTiO 3 (001) substrates are shown to involve strain fields that distort the PZT lattice in a tube of material with a cross-section of about 4 nm × 8 nm around each misfit dislocation. As a consequence, 10 nm thin nanoislandsaround half of their volume being distorted -are not ferroelectric. This finding corresponds to an impact of the interfacial dislocations on the ferroelectric size effect. Moreover, an interface-related, size-dependent imprint effecti. e., a vertical shift of the ferroelectric hysteresis loopwas observed in polycrystalline PZT and epitaxial BaTiO 3 nanoislands. In result, interfacial engineering is indispensable to obtain nanostructured ferroelectrics with stable polarization and switching properties.

High Speed SPM Applied for Direct Nanoscale Mapping of the Influence of Defects on Ferroelectric Switching Dynamics

“…But as individual device sizes continue to shrink, the number of grains per device may not be able to scale proportionally, increasing the importance of the switching response for certain populations of, or even distinct, grain boundaries. Of course grain boundaries have been investigated before with PFM, including studies of domains extending beyond grain boundaries, hysteresis loop acquisition at interfaces, the piezoresponse for grains with dimensions in the nanoscale, and the influence of grains and grain boundaries on coercive fields and domain formation . Focusing on domain dynamics at such an interface, Fig.…”

Impact of misfit relaxation and a-domain formation on the electrical properties of tetragonal PbZr0.4Ti0.6O3/PbZr0.2Ti0.8O3 thin film heterostructures: Experiment and theoretical approach

“…In order to integrate ferroelectrics into suitable devices miniaturization is frequently necessary. At some critical size strains occurring at interfaces become important, [5] enabling strain engineering of the ferroelectric properties, [6] e.g. by growing on different substrates.…”