Amorphous PZT thin films 600nm thick were rf sputtered from a PbZr0.44Ti0.56O3 ceramic target with excess PbO onto glass substrates maintained at room temperature. After irradiation with a 248 nm KrF pulsed excimer laser with a power density of 2.33107W/m2 at a frequency of 50Hz and a pulsed width of 30ns for 2min, the films crystallized into the PZT perovskite structure to a depth of about 120 nm. Comparisons of this work with PZT crystallization obtained from a traditional oven and 488 nm Ar1 laser postdeposition treatments are also given.

BaTi03 thin films were deposited using the r.f. magnetron sputtering technique on unheated fused quartz, poly-crystalline Pt and (111) Si substrates. The films with different grain sizes were obtained through post-deposition heat treatment. The optical transmittance of the films with different grain sizes on fused quartz substrates was measured and the observed shift of the energy gap with grain size was discussed.

Laser (Ar+, Pulsed excimer KrF) crystallization technique was used on if-sputtered amorphous PZT thin films to decrease the substrate temperature during the fabrication of perovskite PZT thin films. The microstructure of the films was compared with those got through traditional oven treatment and rapid thermal process (RTP).

An uneven distribution of stress in the thickness direction was introduced into Landau theory to investigate the critical behavior of phase transition of ferroelectric thin films. The Curie temperature TC was calculated to increase and decrease for compressive and tensile stress cases, respectively. The dispersion of phase transition was predicted. The diffusivity increased with stress, but showed a non-monotonic relation to film thickness. The results of the calculations were compared with some experimental results.

The effect of uniaxial stress on the ferroelectric properties of SrBi2Ta2O9 films with different thicknesses (330, 440, and 660nm) has been investigated. It is found that both the remnant polarization (Pr) and the spontaneous polarization (Ps) decrease with the application of compressive stress, but increase with the application of tensile stress. And the changes of Pr and Ps become larger for thicker films. For the 660nm film, as the stress changed from 2100MPa (compressive) to 1100MPa (tensile), the Pr increases from 21.8% to 11.8%. Testing voltages in the range of 3-6V showed no impact on the amplitude of change on the polarization under mechanical stress. Mechanical stress also did not show significant impact on the coercive field.

The effect of stress on the physical properties of SBT thin films has been investigated. Both Remnant polarization (Pr) and spontaneous polarization (Ps) increase with the application of tensile stress, while decrease with the application of compressive stress. And the variation of Pr increase with the maximum testing voltage in the range 3-12V. The fatigue testing shows that a large voltage cycling before testing and the applied stress are both helpful to preventing the polarization suppression, and the result is explained by the coarsening of domains. The stress about 100Mpa seems to have no observable destructive effect on the SBT thin films.

The effect of poling on the switching properties of SrBi2Ta2O9 films was investigated via the technique of switching current testing. The samples with 660nm thickness were poled under dc voltage ranging from 1 to 8.25V, and for different duration from 1 to 80min. After poling, both the net-switched charge and switching time first jumped to higher values, then decreased with the elapse of time. The decreases were separated into two regimes, a fast and slow regime. The change of net-switched charge and switching time with poling voltage and poling time showed nonmonotonic behavior. These results were explained by the change of domain kinetics and the redistribution of charge carriers under both the applied and depolarization field.

We report on a novel approach for the investigation of the Pb ZrxTi12x)O3/Pt interface applying scanning force microscopy techniques. Ferroelectric samples PZT film/Pt/SiO2/Si) were polished at a shallow angle (～6.1°) thereby enlarging the film cross section from a 430nm film thickness to a width of more than 4mm. Piezoresponse force microscopy and Kelvin probe force microscopy were applied in order to deduce the dielectric polarization P and local potential distribution over the full cross section. We clearly observe a transition layer with a thickness of; 240nm which manifests itself both in a gradual decrease of the piezoresponse signal as a function of film thickness and in a corresponding variation of the surface potential. Furthermore, after polarization reversal due to a dc voltage applied to the tip, a different retention behavior was observed within the transition layer. The results are tentatively attributed to negatively charged defects accumulated at the PZT/Pt interface.

The ferroelectric properties of Bi3.15Nd0.85Ti3O12 and Bi3.25La0.75Ti3O12 thin films under applied uniaxial stress were investigated. It was observed in both films that the remnant polarization sPrd increased with tensile stress, while it decreased with compressive stress. On the contrary, the coercive field sEcd decreased with the stress changing from maximum compression to maximum tension. Fatigue behavior of the films was improved under either compressive or tensile stress compared with zero stress sfree stated. These results can be well explained in the scenario of domain reorientation under stress; however, the polarization-strain coupling mechanism could not be simply ruled out.

Landau–Devonshire theory is used to investigate the effect of external mechanical stress (or strain) on domain structure and the remanent polarization of Pb(Zr0.35Ti0.65)O3 (PZT) thin films, by considering the competition between the external stress and the intrinsic stresses. A set of intrinsic stress functions in PZT film is obtained by solving elastic mechanical equations. At room temperature, the intrinsic stresses may lead to an alternate a/c/a/c domain structure. While an external in-plane tensile stress increases the Gibbs free energy of the c-phase and decreases that of a-phase. Parts of the c-domains turn to a-domains, so as to reduce the remanent polarization of the PZT films.