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In order to develop silicon nitride porous bodies used for the Bio-Filter (the aerobic and anaerobic bacteria consortium supported by a ceramic porous body), suitable sintering aids were examined, which must inhibit densification. It was found that BaCO3, of which decomposition temperature was as high as 1,450 C, was suitable. The porosities of the porous bodies was around 40%, the pore diameter was in a sub-micrometer range (nano-pore), and their strengths were 200~300 MPa. By inserting PE meshes between the green sheets of Si3N4, micro-pores with ~100 micron pore diameter was successfully introduced, and it was found that their strength significantly lowered to around 50MPa.

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WO3-ZrO2 is a promising solid acid catalyst with strong acidity. In this research, tungsten species-dispersed bimodal porous ZrO2 with both continuous macropores and mesopores was prepared by solvothermally introducing tungsten species into the porous ZrO2, which was synthesized by a sol-gel reaction accompanied by phase separation. Subsequent annealing led to precipitation of WO3 fine particles with various size and shape such as nanowires depending on the annealing condition. The acidity and catalytic activity of the prepared WO3-ZrO2 were also investigated.

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Steam electrolysis using strontium zirconate based perovskite type proton conducting oxide was investigated by using different electrode materials, i.e., porous platinum, Sr_0.5Sm_0.5CoO₃ (SSC-55) for the anode and nickel for the cathode, in order to reduce the electrode overpotential and to achieve better energy performance. The SSC-55 anode showed significantly low overpotentials and the nickel cathode exhibited low overpotentials upon the introduction of a SrCe_0.95Yb_0.05O_3-a (SCYb) interlayer. Moreover, a partial substitution of zirconium for cerium in the strontium zirconate electrolyte was found to be effective for improving the current efficiency of the hydrogen evolution rate.

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The microwave tunable capability and its related material optimization of (Ba,Sr)TiO3 thin films in the parallel-plate capacitor form is discussed in terms of the dependence of barium concentration, acceptor doping and in-plane film stress, based on developed wide GHz-band characterization technique under bias field. The barium-content dependence indicates the tradeoff between tunability and dielectric loss, and the notable field-induced loss in SrTiO3 is confirmed as intrinsic Quasi-Debye contribution. The Mg dopant incorporated into perovskite lattice shows almost no effectiveness for tunable device performance except for enhanced insulation as electron acceptor, while less field-sensitivity of the dielectric loss suggests the possibility of partial occupation of the alkaline-earth ion site by Mg. The reduction of in-plane thermal stress controlled by the sputtering deposition pressure leads to higher permittivity and tunability, while the microwave loss remains unchanged, revealing the applicability of sputtering stress control to the microwave device.

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Origins of high Q are considered as high symmetry with inversion, ordering structure, high density, and so on. We would like to discuss the origin of high Q based on the reports concerning to Ba(Mg1/3Ta2/3)O3 (BMT), Ba(Zn1/3Ta2/3)O3 (BZT) and/or Ba(Zn1/3Nb2/3)O3 (BZN) presented by Koga et al., Surendran et al. and Kugimiya.

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FRAM or FeRAM has been in mass production for 15 years primarily in Japan. Yet many challenges remain regarding developing future FRAM devices which require lower voltages, smaller capacitor areas, thinner films, unlimited endurance to read/write cycling and a 10 year lifetime. In this presentation key material and testing challenges for ferroelectric capacitors will be reviewed and discussed. In conclusion, without further R&D on ferroelectric capacitors, FRAM will remain a niche market unable to complete with main stream non-volatile memories such as Flash or EEPROM.

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This presentation describes the design and performance of integrated passives devices (IPDs) on LTCC wiring substrates developed for RF-module applications. The high-Q IPD has been directly fabricated on an LTCC wiring wafer. The LTCC wiring substrate can offer dense interconnects between the integrated passive circuits and the functional devices mounted above the IPD. This technology combines the advantages of LTCC and IPD and is promising for the miniaturization of future RF-modules.

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In recent years, ink-jet(IJ) printing technique is attracted attention as a simple direct wiring and on-demand fabrication method of functional materials for high integration micro electronic devices and micro packaging. In this research, in order to develop a practical IJ wiring technology as material direct writing (MDW), we tried to introduce a laser assistance technique to reduce the expansion of pattern width by wetting properties. By heating a substrate using laser assist, we controlled a spread of a droplet on the several substrates and obtained fine patterning of Ag wire with the width about 10um, high aspect ratio and high throughput over 10mm/sec.

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Aerosol Deposition Method (ADM) is a new technology of ceramics film deposition. For several years, we have been developing this process. In this paper, overview of application to Microwave Imaging sensor on ADM was reported.

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Multi-layer thin film capacitors with multi-terminal electrode structures were prepared directly on various ceramic substrates. SrTiO3 (STO) dielectric thin film, Pt electrodes and the multi-terminal structures in the thin film capacitor were formed respectively by using aerosol CVD, DC sputtering and reactive ion etching (RIE) technologies. The capacitance density of the single-layer thin film capacitor with electrode pad pitch 0.25-1.5 mm reached 60-100 nF/cm2. The effect of surface defects of the substrates on the formation of STO thin film and the performance of the thin film capacitors was discussed.

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In a previous research, the technique of ion-beam-induced in-plane texture control has been successful in buffer layers for superconducting YBCO films. However, few studies have been conducted on ion-beam-induced texture control in piezoelectric films. This technique is important because the piezoelectric and elastic properties of the films change according to their crystallographic orientation. In this study, we will introduce the texture control of (10-10) ZnO films for shear-mode piezoelectric devices.

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Metal oxides with controlled macroporous morphology have been prepared in the monolithic form via the sol-gel process accompanied by phase separation, and light scattering and diffuse transport properties have been investigated. Also, an attempt has been made to induce optical functions by combining optically active molecules and ions.

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We have examined the effect of B₂O₃ addition on 40BaO-20TiO₂-40GeO₂ (BTG40) glass and the BTG40 crystallized glass. With addition of B₂O₃, glass transition temperature of the glass decreased whereas thermal stability against crystallization increased. Although the BTG40 crystallized glass showed bulk crystallization of Ba2TiGe2O8, the BTG40 glass with 10mol% addition of B₂O₃ showed surface crystallization with c-orientation. The correlation between optical nonlinearity and crystallization behavior of the B₂O₃-added BTG crystallized glass will be discussed on the day.

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