A 50 °C shift in Curie temperature has been observed for c-axis oriented PbTiO3 thin films using x-ray diffraction. An analysis of the electrostrictive strain based on the Devonshire thermodynamic formalism showed that the shift in the Curie point for these films can be plausibly explained by an effective two-dimensional compressive stress of ≊400 MPa. The single-domain, single-crystal dielectric susceptibility (η33) and piezoelectric coefficient (d33) were calculated and found to be relatively unaffected, at room temperature, by a compressive stress of this magnitude.

The polarization changes caused by applying mechanical stresses to a lead zirconate titanate (PZT) thin film were investigated. Both the remnant and spontaneous polarizations decreased when the PZT film was loaded with tensile stress. For compressive stresses, the remnant polarization increased, but spontaneous polarization did not change. In fatigue with tensile stress state, the polarization decreased earlier than when there was no stress, which depend on whether or not the initial polarization value was high. Conversely, in fatigue with compressive stress, the initial higher remnant polarization value was maintained compared with the polarization in the unstress condition.

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This paper describes Strain-Imaging observation, using a tunneling acoustic microscope, of lead-zirconate-titanate (PZT) thin films. Strain Imaging detects fine strains generated by the tip voltage in piezoelectric films. This method reveals piezoelectric properties nondestructively with high spatial resolution and is suitable for the characterization of PZT materials for microelectric devices. In Pb(Zr0.5Ti0.5)O3 grown by rf magnetron sputtering, we have observed different properties between round grain structures, so-called “rosettes”, where PZT crystallines have grown from the same cores. This fact shows that not only grain size but also the size of rosettes and the fluctuation of its composition are important factors in the production of homogeneous PZT films.

The origin of orientation in sol-gel-derived PbTi03 films is investigated in detail. Aging of the solution is found to promote (100) orientation of the films. Characterizing the solution by viscometry indicates that the preferred orientation might be attributable to the change of molecular size in the solution. The substrate also influences the film orientation: more strongly (100)-oriented film forms on Pt-coated Si than on fused quartz. Highly c-axis-oriented films with azimuthal orientation are grown on a (100) SrTiO, single-crystal disk.