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)O3 (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 μC 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. Hierarchical PZT nano‐heterostructures are grown on STO:Nb from PZT nano‐seeds using a combined pulsed laser deposition and hydrothermal process. Cross‐linking of the structures result in a dense thin‐film enabling the measurement of the ferroelectric properties without secondary fill‐layer. Well‐saturated and symmetric hysteresis showing high degree of squareness and enhanced remanent polarization are obtained.