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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 structural, magnetic and ferromagnetic properties of polycrystalline BiFe[O.sub.3] films, which are fabricated by a chemical solution deposition on Pt/Ti/Si[O.sub.2]/Si(100) substrates, are analyzed. The magnetoelectric effect of the BiFe[O.sub.3] film is examined by measuring the ferroelectric hysteresis loop under the magnetic field of 5 kG at room temperature.

We report the preparation of (Bi,Pr)(Fe,Mn)O3(BPFM)/SrRuO3 (SRO)-Pt/CoFe2O4(CFO) layered film structure on (100) SrTiO3 substrate by pulsed laser deposition method and their structural and electrical properties. Favorable ferroelectric properties of BPFM were observed in the layered film structure with (100)-oriented growth of BPFM, SRO, and CFO. Variation of polarization vs electric field loops of BPFM by applying DC magnet field was observed, and the remnant polarization was found to increase by 3% with increasing the applied magnetic field from 0 to 10 kOe. The magnetoelectric coefficient in the present structure was estimated to be 1.5 V/(cmOe). [ABSTRACT FROM AUTHOR]

BiFeO3-CoFe2O4 composite thin films were formed on Pt/Ti/SiO2/Si(100) substrates by chemical solution deposition from a mixed precursor solution. X-ray diffraction and transmission electron microscopy analyses confirmed that CoFe2O4 nanoparticles less than 10 nm were uniformly distributed in the BiFeO3 matrix. The BiFeO3-CoFe2O4 composite films exhibited the same ferroelectric switching charge as BiFeO3 thin films, although a larger applied electric field was necessary. However, the magnetic properties were significantly improved by incorporation of CoFe2O4 nanoparticles into BiFeO3; a saturated magnetization of 80 emu/cm3 and a magnetic coercive field of 450 Oe were attained at 300 K. Furthermore, the composite films did not show superparamagnetic behavior in zero-field-cooling and field-cooling measurements, which suggest that the thermal fluctuation of CoFe2O4 nanoparticles was suppressed by exchange coupling with BiFeO3. [ABSTRACT FROM AUTHOR]

Epitaxial (1-x)BaTiO3-xBi(Mg0.5Ti0.5)O3 films with x = 0 - 0.9 were grown on (111)cSrRuO3//(111)SrTiO3 substrates by pulsed laser deposition (PLD). Plotting the temperature where dielectric constant reaches a maximum {T[&eh;r(max.)]} versus Bi(Mg0.5,Ti0.5)O3 content present minimum at x = 0.1. On the other hand, the remanent polarization (Pr) and the effective transverse piezoelectric constant [d33(eff.)] showed minimum at 0.1 and 0.2, respectively, but increased with the increase of x in (1-x)BaTiO3-xBi(Mg0.5Ti0.5)O3 above these values. These results show the simultaneous increase of T[&eh;r(max.)] and d33(eff.) for the films above x = 0.2 that normally showed treads off characteristics. [ABSTRACT FROM AUTHOR]

xBiCoO3–(1-x)BiFeO3 films were deposited by metalorganic chemical vapor deposition. Although the film composition changed with deposition temperature, the composition could be adjusted by varying the input source gas composition at 700 °C. Moreover, adjusting the deposition time could change 0.16BiCoO3–0.84BiFeO3 film thickness. The crystal symmetry changed from rhombohedral to tetragonal as the film thickness decreased for 0.16BiCoO3–0.84BiFeO3 films grown on both (100)SrTiO3 and (100)cSrRuO3∥(100)SrTiO3 substrates, implying that the x value of the crystal symmetry boundaries between the tetragonal and rhombohedral structures changes with film thickness. [ABSTRACT FROM AUTHOR]

Magnetic and magnetoresistance (MR) properties of spin valves composed of Co/Cu/Co/iron oxide layer were studied using epitaxial Fe3O4 (110) grown on MgO (110) as the pinning layer. It was confirmed from the in-plane magnetization curves that the epitaxial Fe3O4 (110) films have the easy axes along the <110> direction and the hard axes along the <001> direction. The spin valves composed of Co/Cu/Co/Fe3O4 (110) showed quite different MR curves depending upon the direction of the magnetic field applied in the plane of Fe3O4 (110). Butterflylike MR curves, which imply the difference in the coercive fields between the top and bottom Co layers, were observed when the field was applied along the <001> direction of Fe3O4. On the other hand, flat MR curves, which implied the difference of the saturation fields between top and bottom Co, were observed when the field was applied along the <110> direction of Fe3O4. The magnetization easy axis of Co layers might be perpendicular to that of Fe3O4. These magnetic and MR properties could be explained by assuming the 90° coupling between the bottom Co and the Fe3O4 layers, and the ferromagnetic coupling (so-called Néel-type coupling) between the top and bottom Co layers. [ABSTRACT FROM AUTHOR]

An interfacial epitaxial BiMn[O.sub.3] layer is prepared by chemical solution deposition on SrTi[O.sub.3] (100) substrate and the microstructure of the film is analyzed by x-ray diffraction (XRD) and cross-sectional transmission electron microscopy (TEM). The analyses have shown that the mismatch between the epitaxial BiMn[O.sub.3] and the SrTi[O.sub.3] substrate have caused a distortion in lattice parameters of BiMn[O.sub.3] and a large compressive strain in the BiMn[O.sub.3] layer.

BiFe[O.sub.3]-based composite films with excess iron content are prepared and the dependence of their magnetic and ferroelectric properties on the excess iron content is examined. The analysis has shown that the specimens are composed of large antiferromagnetic BiFe[O.sub.3] grains and small ferromagnetic component and the grain growth is the main factor for increasing the saturation magnetization and [P.sub.r] along with observing antiferromagnetic coupling at room temperature in BiFe[O.sub.3]-based composite films.

xBiCo[O.sub.3]-(1-x)BiFe[O.sub.3] films are deposited by metalorganic chemical vapor deposition, where the composition is adjusted by varying the input source gas composition and the film thickness is changed by adjusting the deposition time. The crystal symmetry has changed from rhombohedral to tetragonal as the film thickness has decreased, implying that the x value of the crystal symmetry boundaries between the tetragonal and rhombohedral structures have changed with film thickness.

Both the ferroelectric and magnetic properties of polycrystalline BiFe[O.sub.3] films fabricated by chemical solution deposition can be increased by adding small amounts of cobalt. The results have shown that both ferroelectric and magnetic properties are increased when only a small amount of cobalt is added to the films.

Magnetic and magnetoresistance properties of spin values composed of Co/Cu/Co/iron oxide layer were studied using epitaxial Fe3O4 (110) grown on MgO (110) as the pinning layer. It was confirmed from the in-plane magnetization curves that the epitaxial Fe3O4 (110) films have the easy axes along the direction and the hard axes along the direction.