Antimony doped tin oxide thin films were prepared on alumina substrates by magnetron sputtering, and their temperature dependence of electrical resistance at elevated temperature were investigated in relation to the preparation condition. The electrical resistance of as grown films decreased as the substrate temperature during the deposition was increased. By the first temperature cycle of heating and cooling to 500°C, the resistance of the films decreased, and semiconducting properties were observed at following temperature cycles up to 1000°C. A broad resistance increase at 500-600°C region was observed on the films during the measurement in air, on the other hand, the resistance increase was small on the films measeared in low vacuum (-10^-2Torr) . Hence the temperature dependence of resistance of the films showed two linear relations. The films prepared on higher temperature substrates were found to have stable electrical properties than those on lower ones. The as grown and annealed films in air have high transparency at visible region, on the other hand the annealed films in vacuum showed low transparency which recovered the original value by the following annealing in air.

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For a thick film substrate, residual stress generates at the adhesive interfaces of different material on the substrate. It is predicted that cracks occur due to the stress and that a resistance value change of the resistors occur. The authors analyzed the stress of the substrate by using a FEM and clarified the causes based on a FEM analysis result of a substrate cross-section design and reviewed countermeasures. By optimizing the thermal expansion coefficient of each material, they can decrease the residual stress mentioned above and prevent the occurrence of cracks.

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We developed a new catalyst of silver, and examined the characteristics. The silver catalyst was synthesized without expensive palladium and without tin which becomes a catalytic poison. Therefore, the silver catalyst had various characteristics which are different from usual Pd-Sn catalyst. As applying the silver catalyst to the printed circuit board, the superiority of this catalyst became conspicuous. The adsorption-ability and the electroless copper plating deposition-ability of this catalyst were almost equal to those of Pd-Sn catalyst. Moreover, it was proved that most of the adsorbed silver catalyst dissolved in the copper foil etching process during circuit forming of the printed circuit board. As a result, the decrease in the insulation resistance value between the circuits and the deposition over the areas on which no deposition is required (the bridge and so on) can be prevented by using the silver catalyst.

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This paper shows, by experiment, that the use of PCB made of lossy material can efficiently reduce radiated noise from digital circuit. The lossy materials used in our experiment have a dielectric constant of 13 or so, with a wide variety of loss tangents ranging from 0.016 to 0.04. Results of the experiment show that the radiated emission from the circuit is considerably affected by the kind of lossy materials used. It is also found in the experiment that a larger face-to-face area, which has been defined by the author as the area of the Vcc patterns facing the ground plane, will lead to a larger reduction in the noise.

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Anisotropic conducting adhesive technology for flip chip interconnection, being actively investigated now. The new kind of Anisotropic Conductive Film (ACF) we are now developing has the following features:
1. Minimum pitch between conductive material is 0.025mm
2. Conductive material consists of linear metal material (not used small conductive particles)
3. Adhesive material consists of thermoplastic resin
4. Conductive material coated by insulator, which is a high heat distortion resin, is completely separated from the adhesive.

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