A comparative study of fibre-textured and epitaxial Nb-doped Pb(Zr 0.53Ti 0.47)O 3 thin films on different substrates

Abstract

Fibre-textured and epitaxial Nb-doped Pb(Zr 0.53Ti 0.47)O 3 (PNZT) thin films were grown on the different substrates by a sol–gel process. The [1 0 0]- and [1 1 1]-fibre-textured polycrystalline PNZT films were obtained on platinized silicon substrates by introducing PbO and TiO 2 seeding layers, while the [0 0 1]- and [1 1 1]-oriented epitaxial PNZT films were formed directly on Nb-doped SrTiO 3 (Nb:STO) single-crystal substrates with (1 0 0) and (1 1 1) surfaces, respectively. The preferential orientation and phase structure of the fibre-textured and epitaxial PNZT films, as well as their influences on the electrical properties were investigated. Higher remnant polarization ( P r) and piezoelectric coefficient ( d 33) were obtained for the epitaxial PNZT films on Nb:STO substrates than that for the fibre-textured ones on platinized silicon substrates. For both fibre-textured and epitaxial cases, the PNZT films with [1 0 0]/[0 0 1] orientations show higher piezoelectric responses than [1 1 1]-oriented ones, whereas better ferroelectric properties can be obtained in the latter. The intrinsic and extrinsic contributions were discussed to explain the difference in electrical properties for differently oriented fibre-textured and epitaxial PNZT films on different substrates.