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The electrical properties of perovskite-based ferroelectric films were improved by ion modification using rare-earth cations. Thin films of rare-earth-modified lead zirconate titanate [Pb(Zr,Ti)O3] were fabricated on (111)Pt/Ti/SiO2/(100)Si substrates by a chemical solution deposition technique. The substitution of volatile cations in the simple-perovskite oxides, such as Pb2+ in Pb(Zr,Ti)O3 films, enhanced the insulating properties of the film. The crystal anisotropy of the Pb(Zr,Ti)O3 film could be controlled by varying the species and the amount of replacing cations to enhance the spontaneous polarization. Thus, ion modification using Dy3+ cation could enhance the remanent polarization of Pb(Zr,Ti)O3 film consequently.

Our goal was to clarify the high resolution CT (HRCT) findings of community-acquired pneumonia based on pathologic findings and to make a differential diagnosis between bacterial and atypical pneumonias.

Using scanning X-ray microdiffraction with a 50 µm? micro-beam and a newly developed two-dimensional detector, the crystal and domain structures were analyzed for a 2.4-µm-thick epitaxial Pb(Zr0.43Ti0.57)O3film directly underneath a 200 µm? Pt top-electrode before and after applying an electric field. An obvious extrinsic 90°-domain rotation was observed and the volume fraction of c-domain was increased from ?42 to ?71% by an applied electric field over the coercive field. This phenomenon induced a large ferroelectric remanent polarization (Pr?60 µC/cm2) which is an unforeseeable value from an as-grown state of Pb(Zr0.43Ti0.57)O3film.

(100)/(001)-oriented tetragonal Pb(Zr,Ti)O3(PZT) films, which were thicker than 2 µm, were epitaxially grown on SrRuO3-covered (100)Si, (100)KTaO3, (100)SrTiO3, and (100)CaF2substrates by metal organic chemical vapor deposition. The volume fraction of the (001)-orientation almost linearly increased as the thermal strain increased during the cooling process from the deposition temperature to the Curie temperature. Consequently, perfectly (001)-oriented, i.e., polar-axis-oriented, thick films were obtained on CaF2substrates with a remanent polarization of 71 µC/cm2. This approach to grow polar-axis-oriented PZT thick films enabled the intrinsic piezoelectricity of PZT itself to be clarified, and has potential in novel applications.