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The effect of Pb and La contents on the lattice configuration in La-substituted Pb([Zr.sub.0.65],[Ti.sub.0.35])[O.sub.3] (La-PZT) films is examined and La-PZT films with various La and Pb contents are prepared on Pt/Ti/Si[O.sub.2]/Si substrates by chemical solution deposition (CSD). The studies have shown that excess Pd has prevented the A-site substituent of La ions.

The magnetic properties and ferroelectric properties of fabricated BiFe[O.sub.3]-based composite films are discussed. Results suggest the maximum remanent magnetization of approximately 20 emu/[cm.sup.3] and magnetic coercive field of 1.5 kOc.

A chemical solution deposition (CSD) method was used for the fabrication of a multiferroic BiFe[O.sub.3] film on a Pt/Ti/Si[O.sub.2]/Si(100) substrate. Findings reveal the saturation magnetization of less than 1 emu/[cm.sup.3] at room temperature.

The influence of Pb and La contents on the lattice configuration in La-substituted Pb(Zr0.65, Ti0.35)O3 (La- PZT) films was systematically investigated. La-PZT films with various La and Pb contents were fabricated on Pt/Ti/SiO2/Si substrates by chemical solution deposition (CSD). In the La- PZT films with a Pb content ratio of 125% relative to a stoichiometric value, La ions were substituted for riot only A-site ions but also B-site ions at La contents greater than 3 mol%. La substitution for B-site seems to cause larger reduction of the unit cell size. In addition, we found that in the La-PZT films with a La content of 3 mol%, the Pb content of 116 mol% (120% relative to a stoichiometric value) was optimum from the viewpoint of site occupancy. This indicates that excess Pb prevented the A-site substitution of La ions. [ABSTRACT FROM AUTHOR]

BiFeO3-based composite films were fabricated onto the Pt/Ti/SiO2/Si(100) substrates by a chemical solution deposition (CSD) method using the precursor solutions with various excess iron composition followed by annealing at 923 K for 30 minutes under oxygen gas flow. Coexistence of spontaneous magnetization and remanent polarization could be obtained in the BiFeO3-based composite films with high excess iron composition. The remanent magnetization of almost 20 emu/cm³ and the magnetic coercive field of 1.5 kOe were obtained at the iron composition ratio of Fe/Bi = 1.25. In this specimen, the remanent polarization at 90 K was approximately 10 µC/cm² at the electric field of 1500 kV/cm. Structural analysis suggested that the remanent polarization has a possibility to increase by suppressing the formation of the secondary phases of Bi2Fe4O9 and α-Fe2O3, these are the nonferroelectric material as well as antiferromagnetic phase. [ABSTRACT FROM AUTHOR]

A multiferroic BiFeO3 film was fabricated on a Pt/Ti/SiO2/Si(100) substrate by a chemical solution de- position (CSD) method, and this was followed by postdeposition annealing at 923 K for 10 mm in air. X-ray diffraction analysis indicated the formation of the polycrystalliae single phase of the BiFeO3 film. A high remanent polarization of 89 µC/cm² was observed at 90 K together with a relatively low electric coercive field of 0.32 MV/cm, although the ferroelectric hysteresis loops could not be observed at room temperature due to a high leakage current density. The temperature dependence of the ferroelectric hysteresis loops indicated that these hysteresis loops lose their shape above 165 K, and the nominal remanent polarization drastically increased due to the leakage current. Magnetic measurements indicated that the saturation magnetization was less than 1 emu/cm³ at room temperature and increased to approximately 2 emu/cm³ at 100 K, although the spontaneous magnetization could not appear. The magnetization curves of polycrystalline BiFeO3 film were nonlinear at both temperatures, which is different with BiFeO3 single crystal. [ABSTRACT FROM AUTHOR]

Abstract: R 3Ga5SiO14 (RGS, R: rare-earth elements) and RCa4O(BO3)3 (RCOB) single crystals were synthesized by the Czochralski technique and their piezoelectric properties were investigated. The piezoelectric moduli, d 11 and d 14, of La3Ga5SiO14 are higher than those of Nd3Ga5SiO14. Moreover, in the RGS-type crystal, we found that the piezoelectric modulus, d 11, increased with the lattice parameter a. The ionic size preferences of all cation sites in the RGS-type structure were also clarified. Based on these results, a new RGS-type Ba3TaGa3Si2O14 crystal was synthesized. We have successfully grown RCOB (R =La, Nd, Gd, Dy, and Y) single crystals with 1 and 2in. diameter dimensions. The surface acoustic wave (SAW) properties of RCOB filters were investigated. In RCOB, the NdCOB single crystal showed the highest electromechanical coupling factors and lowest temperature coefficient of delay of the RCOB crystals. [Copyright &y& Elsevier]