Phase structure of epitaxial Pb(Zr,Ti)O3 thin films on Nb-doped SrTiO3 substrates

Abstract

Epitaxial Pb(Zr,Ti)O3 (PZT) films were deposited on Nb-doped SrTiO3 (Nb:STO) monocrystalline wafers by a sol-gel method. It was observed that phase structure of prepared films depends on the orientation of Nb:STO substrates. Interestingly, tetragonal structure was only found for [001]-oriented PZT film on Nb:STO(100) substrate, whereas Nb:STO(111) substrate resulted in a [111]-oriented rhombohedral PZT film, regardless of Zr∕Ti ratios ranging from 40∕60 to 60∕40. The influence of substrate orientation on phase structure of epitaxial PZT films was discussed on basis of the lattice matching. Ferroelectric and piezoelectric properties of PZT films on different Nb:STO substrates were also studied.

Shifting of the morphotropic phase boundary and superior piezoelectric response in Nb-doped Pb(Zr, Ti)O3 epitaxial thin films

“…However, it is difficult to fabricate epitaxial PZT thin films with an MPB phase structure which may be caused by biaxial compressive stress in epitaxial films resulting in changes in the phase structure, as suggested by Oh et al [9]. The prediction is consistent with our previous study [13,14] where we found that epitaxial PZT thin films could be formed on Nb-doped SrTiO 3 substrates by a sol-gel process. Their phase structures can be substantially affected by the substrate orientations due to the mechanical constraints, motivating us to systematically investigate the compositional dependence of the phase structure and electromechanical properties of epitaxial PZT thin films in a broad compositional range using combined experimental and theoretical approaches as are shown in this report.…”

“…The observed fourfold symmetry (not shown) clearly indicates a well epitaxial relationship between the deposited PNZT films with different Zr/Ti ratios and the Nb:STO(1 0 0) substrates. This result is consistent with our previous work [14]. In order to examine a possible phase transition when the Zr/Ti ratio is changed, the (0 0 4)-reflections of films are precisely step-scanned (Fig.…”

“…In addition, ab initio studies revealed a previously unknown phase transition in zerodimensional PZT nanoparticles which is profoundly different from bulk PZT materials [12]. Compared to bulk polycrystalline counterparts, epitaxial PZT thin films are more useful due to their monocrystalline-like characteristics, and much research has been conducted to study epitaxial PZT films [13][14][15]. However, it is difficult to fabricate epitaxial PZT thin films with an MPB phase structure which may be caused by biaxial compressive stress in epitaxial films resulting in changes in the phase structure, as suggested by Oh et al [9].…”

Ordered Mesoporous Thin Film Ferroelectrics of Biaxially Textured Lead Zirconate Titanate (PZT) by Chemical Solution Deposition

“…In the range of 2θ from 18° to 52°, only two peaks -namely, the (001) and (002) reflections -corresponding to the perovskite PZT phase can be observed. 55 In addition, HRXRD indicates the epitaxial growth of single-phase, fully strained LSMO(00l) with lattice parameter c = 3.85 Å on (001)-oriented STO:Nb; more details are given elsewhere. 43 To better characterize the crystallinity of the mesoporous PZT with regard to texture and uniformity, both a φ scan, by tilting to 44.56°, on the (110) reflection and an ω scan (rocking curve measurement) on the (001) reflection at 2θ = 21.84° were conducted.…”

The effect of misfit strain on the phase diagram and pyroelectric effect in (110) oriented Pb(Zr1−xTix)Qiu1, Chen2, Wang3 et al. 2016Solid State Communications11010View full textAdd to dashboardCite

“…Many of these properties are maximized near the morphotropic phase boundary (MPB) with a Ti composition of 0.48 [3][4][5][6]. Moreover, orientation engineering is a suitable approach to improve the physical properties of the PbðZr 1 À x Ti x ÞO 3 thin films [7][8][9][10]. Therefore, control of the composition and film orientation can be used to modulate the physical properties of the ferroelectric thin films.…”