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Barium titanate (BaTiO3) nanoparticles were prepared by 2-step thermal decomposition method from barium titanyl oxalate nanoparticles with a size of 30 nm. When normal oxalate with size of 0.2 mm was used, temperature of 1st step was 500 ˚C while at 2nd step, BaTiO3 was formed over 590 ˚C. On the other hand, when nano oxalate with size of 30 nm was used, temperature of 1st step was 460 ˚C while at 2nd step, BaTiO3 was formed over 550 ˚C. Thus, the use of nano oxalate made temperature of BaTiO3 formation lower.

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In this study, barium titanate (BaTiO3, BT) and strontium titanate (SrTiO3, ST) nanocube particles were successfully prepared by solvothermal method. As the raw materials, barium hydroxide, strontium hydroxide and titanium dioxide nanoparticles were used, and as the solvent, ethanol and 2-methoxy ethanol were used. Size of the obtained BT and ST nanoparticles was around 20 nm, and their crystal structures were assigned to cubic m-3m symmetry. Using these nanoparticles, their accumulation was investigated.

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We have developed manipulation method of nanostructured materials by dielectrophoresis and traveling wave dielectrophoresis system designed on large scale glass substrate using liquid-crystal display related COG (chip on glass) technologies. Fine pitch prallel electrodes were formed with from 1 mm to 15 mm L/S (line/space) on the glass substrate, and then resist passivation film was coated on the electrodes. The high-frequency electric field was applied to the electrodes using flexible circuit board. We successfully demonstrated manipulation and distribution of nanostructured materials, i.e., multiwall carbon nanotubes, TiO2 rutile particles, BaTiO3 nanopowders.

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Recently, we have proposed novel orientation control of sol-gel derived films using oxide nanosheets as a seed layer. In this study, we tried to apply this technique to a film fabrication via dry-process. SrTiO3 thin film was deposited on the nanosheet seed layer by pulsed laser deposition, and succeeded to fabricate well crystallized (100) oriented SrTiO3 thin films.

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Preparation of PbTiO3 nano-crystals have been interesting as investigation of ferroelectric size effect, high quality ultra thin film growth and nano-scale storage media. In this study, formation of atomically flat surface of sapphire and growth of PbTiO3 nano crystals on the surface by sputtering were investigated. The atomically flat surface with step-terrace structure was obtained by annealing at 1000oC, and the PbTiO3 deposition on the surface was performed. The surface morphology of obtained specimen was observed by AFM. The dependences of the morphology on annealing temperature, mis-cut angle and deposition rate were investigated. The nano crystals with near uniformity were grown at step edge at low growth rate deposition, revealing that the self-assembled nano crystals can be obtained on atomically flat substrates of sapphire with optimize growth condition.

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A new compound, pyrochlore phase of tin(II) titanate, was prepared under mild conditions by a microwave assisted solvothermal method. The chemical composition of this compound could be expressed as Sn_1.30Ti_2.00O_3.60(OH)_1.85F_1.55, showing large amount of Sn(II) defect. The powders could be sintered to almost full theoretical density by a hydrothermal hot-pressing method at low temperature such as 270degree.

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Temperature dependence of dielectric loss of the Ba(Mg_1/3Ta_2/3)O₃(BMT). dielectric loss was decreased with temperature decreasing up to 200K and showed increasing having a peak at 40K. It was inferred that this temperature dependence was due to both 2 phonon difference process and local polarization of the BMT. The local polarization had the relaxation at the MW range because this loss increasing did not appear at millimeter wave frequency.

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The diamond photonic crystals with periodic arrangement of dielectric media were fabricated, and millimeter wave localization behaviors in introduced structure defects introduced were investigated. Acrylic diamond lattice structures with TiO2 dispersion at 40 vol. % were fabricated by Microstereolithography. After removing acrylic resin by heating in air at 600 deg C for 2 hours, the sample was sintered at 1350 deg C for 2 hours. The electromagnetic properties of sintered samples were measured with network analyzer and W-band millimeter waveguide in the range from 75 GHz to 110 GHz. The behavior of the defect mode will be reported.

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This talk reviews explorative research of new functionality in ceramics using ubiquitous element utilizing nanostructure. The hidden potential of this strategy is exemplified by showing recent finding of metallic state and superconductivity in 12CaO·7Al2O3 which is known as a component of aluminous cement, and recent progresses in oxide electronics.

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Isotope heterostructures of zinc oxide thin films were used to study diffusion characteristic by means of a secondary-ion mass spectrometry (SIMS). The films were deposited on a-plane sapphire substrates by pulsed laser deposition method. The isotopic depth profiles were fitted a simple solution with error functions that is applied the diffusion of internal layer. The diffusion coefficient was successfully obtained without an evaporation and surface reaction effect.

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Ferroelectric gate transistor is expected as next generation non-volatile memory. There are, however, several issues at the ferroelectric/semiconductor interface. The use of oxide channel should be the solution for the issues. In this paper, ferroelectric gate TET was fabricated using ZnO channel. Bottom gate TFT showed a relatively large ON current. Detailed studies on dielectric properties revealed that the ON current includes ferroelectric polarization together with some other space charge effect.

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We have measured AC-conductance (@50Hz) of ZnO varistor contained about 5mol% additives (Bi203, Sb203, etc.) and obtained the nonlinear conponent of current responses. Activation energy (Ea) was determined by Arrhenius-Plots of peak current values of the nonlinear responses. The Ea against Vp-p was almost constant in the low voltage region, and those in the high voltage region decreased steeply as increase of Vp-p. Ea was about 0.2 eV in the flat region, while the intercept of Ea regarding to the high voltage region was estimated to be about 4 eV by extrapolation of the straight line. We assumed that the intercept of Ea and the flat Ea were corresponding to barrier height at a thin grain-boundary along ZnO grains and activation energy of a thick grain-boundary of triple point neighbor, respectively.

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ZnO thin films were prepared by electrochemical deposition method on Au electrode with constant potential (C.P.) and constant current conditions. The working electrode was irradiated with ultraviolet (UV) light during a deposition. The electrolysis current in C.P. condition was increased by UV irradiation, which is probably caused by photo-carrier generation in the deposited ZnO layer. The film thickness of a film with UV was larger than that grown in dark, because of shorter deposition term and lesser re-solution during a deposition caused by the larger electrolysis current. The edges of hexagonal grains grown under irradiation of UV were sharper than that in the dark.

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Very thick (Zn,Mg)O films with various MgO fraction were grown by a liquid phase epitaxy (LPE) method on ZnO substrates in order to obtain suitable substrate material for development of ZnO based electric devices including light emitters. The highest MgO fraction achieved in this study was about 13% and the properties of the obtained (Zn,Mg)O films followed Vegard's law. Detail of the structural features and electric and optical properties will be discussed.

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To make clear the original characteristics of Pb(Zr,Ti)O3, PZT, single crystalline thick films around 4 m in thickness were grown using the strain from the substrates. This is useful to make clear the piezoelectric properties of PZT itself, but also for the practical applications, using these as seed crystals.

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Full-dense Pb(Zr,Ti)O₃ (PZT) ceramics with thickness of 300 m were successfully obtained by aerosol deposition (AD) employing the starting powder subjected to an adequate pretreatment. It was found that formation of internal pores during the post-deposition firing treatment takes place in the two different mechanisms on different scales. Residual carbons contained in the as-deposited PZT ceramics are responsible for the formation of extra-large pores inducing a severe distortion to the shape of the sample. On the other hand, trapped agglomerated particles in the as-deposited PZT ceramics are responsible for the formation of intermediate pores. The relevant mechanisms are discussed with a focus on the positive/negative correlation between the pretreatment of starting powders and the formation of internal pores.

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A new technique for the separation of metals such as Bi and Pb from borate-based glasses has been proposed, in which metal nitrides such as AlN are added to the glasses containing Bi or Pb ions and melted at temperatures of around 1200oC. Metal nitrides act effectively as reducing reagents for Bi and Pb ions, producing the precipitation of those metals. The relation between the amount of metal nitride additions and the amount of precipitated metals is examined.
This new technique will apply for the recovery of metals in waste glasses and for the fabrication of metal nano-particles in glasses.

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The reactions between refractories and lead glasses were investigated in general for the reaction mechanism at high temperature. These investigations have discussed the corrosion of refractories by glasses. On the other hand, the investigations for the quality of glasses by refractories are not so much. Therefore, for glass quality level up, this report was studied at low temperature for the reaction between refractories and lead glasses. Especially, the glass quality research and the countermeasure suggest the quality level up method according to the improved refractory treatment.

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