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Polycrystalline holmium iron garnet Ho3Fe5O12 with grain size of about 2 μm was prepared by a solid-state reaction method. A dielectric relaxation behavior was observed and it can be ascribed to the charge carrier hopping between Fe2+ and Fe3+. In addition, a spin-glass transition at about 110 K associated with the coexistence of Fe2+ and Fe3+ was also observed in Ho3Fe5O12 ceramics. Both the dielectric relaxation behavior and spin-glass transition were further verified by the internal friction spectrum.

Nanoscale ferroelectric materials are candidates for ultrahigh density ultralarge scale integrated memory chips. In this paper, we fabricated one coating of neodymium substituted Bi4Ti3O12 nanostructures on Pt/Ti/SiO2/Si substrates. The method we used here was spin coating precursors with a series of concentration on the substrates and then annealing at 750°C, 800°C and 850°C in the oxygen atmosphere to get the self-patterning nano particles. X-ray diffraction (XRD), scanning probe microscope (SEM) and Scanning probe microscope (SPM) detections were performed on the high temperature annealed samples to reveal the surface morphologies and the crystalline microstructures. It is found that when the annealing temperature is higher than 800°C, the Pt substrates nearly have no effect on the surface of the samples; and the average height of the nano particles is enhanced to approximately 50 nm.

δ-Bi2O3 has attracted extensive attention in recent years for its high ionic conductivity especially at high temperatures. The bismuth sesquioxide can serve as the potential top electrodes of the Bi-containing ferroelectric thin films. In order to investigate the property of self-patterning Bi2O3, the self-assembled bismuth oxide was fabricated on Pt/Ti/SiO2/Si substrates and the Bi3.25La0.75Ti3O12 thin films. The method we used here was spin coating the Bi-containing precursors on the substrates and then annealing in the oxygen atmosphere to get the self-patterning Bi2O3 particles. To avoid the affection of the substrate to the largest extent, the substrates were annealed first for different time in oxygen atmosphere in order to select appropriate conditions. Scanning probe microscope (SPM), scanning electron microscope (SEM) and the x-ray diffraction (XRD) were used to detect the morphology and the structure of the particles mentioned above. It showed that the change from separated particles to...

For the sake of fabricating the ultrahigh density ultralarge scale integration (ULSI) memory chips, the ferroelectric nanostructures growth through self-assembly are studied. In this paper, we synthesize the lanthanum and niobium substituted Bi4Ti3O12 nanostructures on Pt/Ti/SiO2/Si substrates. The method we used here was spin coating precursors with a serious of concentration on the substrates and then annealing at 700°C or 750°C in the oxygen atmosphere to get the self-patterning nano particles. Scanning probe microscope (SPM), and x-ray diffraction (XRD) were used to detect the morphology and the crystalline structure of the nano particles. The well-separated Bi3.15Nd0.85Ti3O12 particles have a typical lateral size about 100–150 nm and height about 20–25 nm. XRD reveals pyrochlore phase in the low concentration samples. The lower the precursor's concentration is, the higher the excess of Bi element is needed to form the pure perovskite nanoparticles.

The Bi 3.25 La 0.75 Ti 3 O 12 (BLT) thin films prepared by metal-organic decomposition method on Pt/Ti/SiO 2 /Si substrates were investigated. Electrical measurements demonstrated that the polarization decay increased with increasing the write/read voltages within the first 100 seconds. This phenomenon was attributed to the depolarization field, which increases with increasing the retained polarization. Long time retention measurement showed that the BLT films possessed outstanding retention character, the polarization loss ratio was quite small with respect to the initial values.

Laser (Ar+, Pulsed excimer KrF) crystallization technique was used on rf-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)

Structural phase transformations from pyrochlore and amorphous phases to perovskite phase were studied in PZT thin films deposited by RF magnetron sputtering technique. We have investigated the effect of fabrication conditions on this transformation usingX-ray diffraction, SEM and ICP techniques, and paid special attention to the differences between transformation from pyrochlore to perovskite and that from amorphous to perovskite. The possible reasons for affecting this transformation were discussed.