One-Axis-Oriented Crystal Growth of Lead Zirconate Titanate Thin Films on Metal Substrates Using Perovskite-Type Oxide Nanosheet Layer

Abstract

One-axis-oriented Pb (Zr,Ti)O3(PZT) films were fabricated using a chemical solution deposition technique on (111)Pt/TiO2/(100)Si and Inconel625 substrates buffered by nanosheet Ca2Nb3O10(ns-CN). The (001)-oriented PZT crystals (Zr/Ti=0.40:0.60, tetragonal) were preferentially grown on (001)ns-CN/Inconel625, whereas the PZT crystals deposited on (001)ns-CN/(111)Pt/ TiO2/(100)Si exhibited preferential PZT(100) orientation. The resulting PZT film on (001)ns-CN/Inconel625 indicated remanent polarization of approximately 59 μC/cm2, which was significantly larger than that on (001)ns-CN/(111)Pt/TiO2/(100)Si.

Influence of the Template Layer on the Structure and Ferroelectric Properties of PbZr0.52Ti0.48O3 Films

“…These functional properties of PZT thin films are highly dependent on several material properties, such as the stoichiometry, crystal orientation, and microstructure. The most favorable properties of PZT are found in the x = 0.48 morphotropic phase boundary (MPB) composition. − It has been shown theoretically , and experimentally − that the PZT grown in the (001) orientation, which is the out-of-plane direction, exhibits a higher functional response than do other orientations, hence the PZT films have been initially grown on lattice-matched SrTiO 3 substrates to promote such oriented growth. , To grow (001)-oriented PZT on low-cost substrates such as Si, glass, and metals, several buffer layers have been explored. − In particular, it has been shown that chemically synthesized unit-cell-thick oxide nanosheets can be used to achieve the desired out-of-plane crystal orientation on silicon and glass substrates. − Given the right stoichiometry and orientation, the ferroelectric response is further affected by the microstructure of the film, which is affected by the grain size and domain structure. ,, The film microstructure also influences the application-relevant piezoelectric properties by influencing the elastic parameters of the film. − Therefore, it is important to explore the methods that allow the film microstructure and consequent influences on the film’s functional properties to be controlled.…”