Nanosheet Ca2Nb3O20 (ns-CN) layers with pseudo-perovskite-type crystal configuration were applied on the surface of polycrystalline metal substrates to achieve preferential crystal orientation of Pb(Zr,Ti)O3 (PZT) films for the purpose of enhanced ferroelectricity comparable to that of epitaxial thin films. PZT films with tetragonal symmetry (Zr/Ti = 0.40 : 0.60) were fabricated by chemical solution deposition (CSD) on ns-CNbuffered Inconel 625 and SUS 316L substrates, while ns-CN was applied on the the substrates by dip-coating. The preferential crystal growth on the ns-CN layer can be achieved by favorable lattice matching between (001)/(100)PZT and (001)ns-CN planes. The degree of (001) orientation was increased for PZT films on ns-CN/Inconel 625 and ns-CN/SUS 316L substrates, whereas randomly-oriented PZT films with a lower degree of (001) orientation were grown on bare and Inconel 625 films. Enhanced remanent polarization of 60 μC/cm2 was confirmed for the PZT films on ns-CN/metal substrates, ascribed to the preferential alignment of the polar  axis normal to the substrate surface, although it also suffered from higher coercive field above 500 kV/cm caused by PZT/metal interfacial reaction.
ASJC Scopus subject areas
- Physics and Astronomy(all)