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Temperature dependence of the PMN-PNN-PZT thin films prepared by chemical solution deposition are investigated. Polarization hysteresis loops are slim and non-linear. Dielectric constant of the films is 2000. Linear field-induced displacement curves are obtained, and coprreswponding d33 is 70pm/V.

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Temperature dependence on the property of lead-free piezoceramics, (1-x)(Na_0.5K_0.5)NbO₃-xLiNbO₃ (LNKN), has been investigated. The measured piezoelectric properties were quite defferent among the chemical compositions near its morphotropic phase boundary (x=0.06). It was found that the variable elastic compliance strongly correlated to these changes, and was originated from a slight amount of changes in the crystal structure as well as secondary phases. This was also discussed by the Raman spectroscopic analysis.

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BatiO3 sample of the nanopowder fabricated by hydrothermal synthesis has a high piezoelectric constant d33 due to fabribation by microwave sintering. The maximum value of the piezoelectric constant d33 of a specimen fabricated by microwave sintering was apporoximately 350pC/N for a grain size of 0.0021mm. The size of ferroelectric domains in the samples showing superior piezoelectric properties was less than 50nm. Grain boundaries characteristic confirmed that the fraction of random boundaries was higher by approximaterly 10% in microwave sintered samples than in conventionally sintered ones.

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Embedding various passive elements, such as capacitors, filters, and inductors, in one system module, is an effective way to achieve miniaturization, cost reduction, and higher performance in RF communication products. Low Temperature Cofired Ceramics (LTCC) is one of the current promising technologies for obtaining the embedded module. However, one drawback is relatively high-cost. For low-cost RF modules in next generation, we propose a resin built-up circuit board embedding the ceramic passive film using the unique aerosol deposition (AD). This circuit board makes it possible to obtain all of the above demands simultaneously. AD making use of the solidification with bombardment of nano-size ceramic particles can form a ceramic-film below endurance temperature of resin. Therefore, this deposition is the key method for our proposed printed wiring board (PWB) embedding the passive elements. We present the microstructure and properties of the BaTiO3 AD film for the decoupling capacitor in a PWB.

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We characterized the crystallographic structure of oxidized layer of TiN thin film that exhibits high-speed resistive switching using high-resolution scanning transmission electron microscopy (HR-STEM). The electron energy dispersive spectroscopy (EDS) mapping indicates a few nano-meter thick of TiO2 nano-crystalline layer on TiN thin film. Further, the the nanocrystalline layer was identified as TiO2 anatase from the electron energy loss near-edge structure (ELNES) of electron energy loss spectroscopy (EELS) and high-resolution transmission electron microscopy (HR-TEM) image. The obtained results concide with the temperature dependence of of resistivity of the film which suggests Mott transition of TiO2 anatase.

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Relaxor ferroelectrics are used as dielectrics in Y5V MLCCs and the shell of X7R MLCCs. The relaxor behavior affects the properties of MLCCs. In this presentation, the mechanism of diffuse phase transition in relaxors is reviewed as introduction. Properties of X7R MLCCs with different dielectric grain sizes were measured analyzed using spline and least-squares analyses to evaluate the properties of MLCCs with dielectric grains less than 100 nm. The results showed a thickness limit of dielectric layers exists for the improvement of the capacitance density. Domain effects on the dielectric properties and the possibility to use lead-free relaxors in the core of X7R MLCCs are discussed as a design concept of the future MLCCs.

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In the material with photorefractive effect, refractive index is changed according to the light intensity distribution. With the combination of the large piezo electric effect and photo elastic effect, huge photorefractive effect is expected in relaxor ferroelectric crystals. We will report some experimental results of photorefractive effect in 0.91Pb(Zn_1/3Nb_2/3)O₃-0.09PbTiO₃ and effect of dopings.

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Lead free PTC ceramics was developed by adding (Bi_1/2Na_1/2)TiO₃ instead of PbTiO₃ to BaTiO₃ as a Tc shifter. The high quality lead free PTC ceramics was obtained by preparing under the optimized conditions. The electrical properties, grain boundary resistance, ICTS spectra and so on were measured in this investigation.

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Metamaterials are a new class of ordered composites that exhibit exceptional electromagnetic properties no readily observed in nature. Especially, these artificial materials with simultaneously negative permittivity and permeability properties have attracted widespread interest in recent years. Recent research activities on metamaterials have not only demonstrated interesting physical phenomena but also lead to the developments of design procedure and the realization of promising new type of microwave and millimeter-wave components and devices. In this presentation, we make a survey of metamaterials and RF applications.

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The reflection intensity measurement was carried out using non-contact probe for BaTiO3 single crystal and inner dielectric and electrode layers for cross section of multi-layer ceramic capacitor. The spatial resolution of dielectric measurement using non - contact microwave probe was improved following the basis of Kirchhoff's diffraction formula with decreased diameters of the coaxial cable and probe. Using reflection intensity mappings, the dielectric permittivity distribution in micro-region at 9.4 GHz was measured for the cross section of multi-layer ceramic capacitor at room temperature. The spatial resolution was experimentally estimated to be about 10um from mappings of the dielectric and inner electrode layers in the multi - layer ceramic capacitor.

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Recently MgTiO3 has gotten a lot of attention for High Q value material of electrical resonator. We focus that point and we are researching that material, especially nano-size one. Nano-size MgTiO3 was synthesized by sol-gel method using citric acid as matrix. A TiCl4 solution was hydrolyzed and a stoichiometric amount citric acid and MgO were first dissolved under stirring condition. The dried gel was heat-treated at temperatures between 300 and 900 oC. X-ray powder diffraction (XRD) was used to characterize the samples. Transmission electron microscope (TEM) was used to directly observe surface morphology, respectively. The high crystalline nano-size product could be obtained at these conditions. The particle sizes of the powders are between 80 and 200 nm, respectively, which were obtained from the TEM micrographs. The agglomerates of the particles disturb the estimate of the size, and the appearance of large particles might be the agglomerate of the small ones. Further, in poster presentation, the dielectric constant affected by crystallinity will be reported.

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Nano-sized barium titanate particles have prepared by sol-gel method. And barium titanate thin films have been prepared by coating the nano-sized barium titanete particles dispersed solution. In this study, in order to fabricate the film capacitor, we made barium titanate thin films onto copper substrate, and the characteristic evaluation was carried out. Then, the dielectric constant was 150, and the dielectric loss was 3%.

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