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Effects of the thermal treatment and the fabrication process of Pb(Zr0.3Ti0.7)O3 (PZT) thin films using chemical solution deposition on Pt/TiOx electrode stacks were investigated using complementary analytical techniques including atomic force microscopy (AFM), x-ray photoelectron spectroscopy, high-resolution transmission electron microscopy, and grazing incidence x-ray reflectivity of synchrotron radiation. The surface and interface structures of the Pt/TiOx electrode stacks with different thermal treatments, and the PZT/Pt/TiOx sample were examined. The propagation of Pt hillocks on the bare Pt/TiOx electrode stacks upon the annealing was observed. AFM observations also revealed that the upper surface of the Pt bottom electrode under PZT thin film became rougher than that of the bare Pt electrode with the same thermal history. Global structural information including the density, surface or interface root-mean-square roughness, and thickness of each constituent layer in the samples were determined using x-ray reflectivity. A density decrease of the Pt layer upon the annealing or during the fabrication of PZT thin films was found from fitting the specular reflectivity, and further confirmed by the negative shift of the Yoneda peak of Pt in the diffuse reflectivity. The formation of Pt hillocks on the bare Pt electrodes was attributed to the compressive stress during the high-temperature annealing caused by the limited incorporation of Ti and O into the Pt layer. Roughening of the PZT/Pt interface was ascribed to the interaction between the compressive stress in Pt and the indentation by the PZT crystallization and grain growth during the annealing. [ABSTRACT FROM AUTHOR]

The effects of thermal annealing on Pb(Zr0.3Ti0.7)O3 ferroelectric thin film capacitors derived by chemical solution deposition with Pt electrodes were investigated. Sample-averaged structural information of the capacitors with different thermal histories was obtained from fitting the X-ray specular reflectivity using a homogeneous stratified multilayered structure model of Pt/PZT/Pt/TiOx/SiO2. Electrical measurements showed a remarkable remanent polarization reduction of up to 8.8% and an increase of the dielectric constant at low biases with increasing annealing time from 5 to 10 min. However, no evident change to the fatigue endurance was found except for the reduced initial remanent polarization. The effects of the thermal annealing on the electrical propel-ties of the ferroelectric capacitors are discussed in correlation with the structural changes in the ferroelectric thin films. [ABSTRACT FROM AUTHOR]

The effects of thermal annealing on the structure of polycrystalline Pb(Zr0.3Ti0.7)O3 (PZT) ferroelectric thin films prepared by chemical solution deposition on Pt/TiO x electrode stacks were studied using scanning electron microscopy, transmission electron microscopy (TEM), and grazing incidence X-ray specular and diffuse reflectivity of synchrotron radiation. The stratified multilayered structure and element diffusions in the sample were characterized by TEM. Global statistical structural parameters including the density, surface or interface roughness and thickness of each layer in the samples were obtained from fitting the X-ray specular reflectivity using a homogeneous stratified multilayer model of PZT/Pt/TiO x/SiO2. The results showed that the PZT surface and PZT/Pt interface roughness changed slightly during thermal annealing in oxygen at 700°C. By contrast, the density increase of the PZT ceramic and density decrease of the Pt-bottom electrode during annealing were observed. A high density value of the PZT ceramic film after the annealing was found, up to 99.8% of the theoretical value of the corresponding bulk ceramics. The density changes of the PZT and Pt layers were further confirmed by X-ray diffuse reflectivity. The influences of the annealing treatment on the density changes of the PZT and Pt layers were attributed to the further densification of the PZT ceramic and incorporation of light elements such as Zr, Ti and O from the neighboring layers into the Pt layer, respectively, as discussed in correlation with the TEM analyses. [ABSTRACT FROM AUTHOR]

Structural investigations of Pb(Zr,Ti)O3 (PZT) ferroelectric thin films derived by chemical solution deposition on Pt/TiOx electrode stacks were performed using grazing incidence x-ray specular reflectivity of synchrotron radiation and transmission electron microscopy. A density inhomogeneity, i.e., a sublayer structure, in the PZT thin films was observed; the upper PZT sublayer had a lower density and the lower sublayer had a higher density. The influence of the density inhomogeneity, as a possible extrinsic contribution to size effects in ferroelectric thin films, was discussed. [ABSTRACT FROM AUTHOR]

A correction to the article "Effects of Thermal Annealing on the Structure of Ferroelectric Thin Films," published in the 2006 issue is presented.