Hierarchically Ordered Nano-Heterostructured PZT Thin Films with Enhanced Ferroelectric Properties

Realization of ferroelectric (FE) devices based on the polarization effects of Pb(Zr0.52Ti0.48)O-3 (PZT) has reinforced the investigation of this material in multiple dimensions and length scales. Multi-level hierarchical nanostructure engineering in PZT thin films offer dual advantages of variable length-scale and dimensionality. Here, the growth of hierarchically ordered PZT nano-heterostructures (Nhs) from PZT seed-layer deposited on SrTiO3:Nb (100) substrates, using a physical/chemical combined methodology involving pulsed laser deposition (PLD) and hydrothermal processes, is reported. Systematic SEM, TEM, and Raman spectroscopy studies reveal mixed hetero- and homo-epitaxial growth mechanism. In the final stage, 3D Nh units cross-link and form a dense network-like Nh PZT thin-film. FE polarizations are measured without using any polymer fill-layer which otherwise introduces huge dielectric losses and lowers the polarization values for a FE device. In benefit, well saturated and symmetric FE hysteresis loops are observed with high degree of squareness and a high remnant polarization (54 C cm(-2) at a coercive field of 237 kV cm(-1)). This work provides a pathway towards preparing hierarchical PZT Nhs offering coherent design of high-performance FE capacitors for data storage technologies in future.