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Beta alumina (Na2O·11 Al2O3) with addition of MgO, NiO, ZnO, CuO and CaO, respectively, together with Na2O are sintered. Ionic conduction of Na+ and X-ray diffraction of these samples are investigated. Additions of above divalent ions, except for Ca2+, increase the amount of Na+ in β-alumina, leading to an increase in the ionic conduction of Na+ in β-alumina. All divalent ions effective to increase the ionic conduction are components of aluminum spinel. The limiting process of the D.C. ionic conduction of these sintered samples may be the grain-boundary conduction.

SnO2 thin films having low resistivity were prepared by chemical vapor deposition. Conductivity, its dependence on temperature, and Hall effect of films were measured. Examination of the surface morphology by scanning electron microscope showed that the SnO2 thin films are made up of many grains. Experimental results were discussed by the grain-boundary model. The carrier transport mechanism across a grain boundary is the tunnel effect rather than the thermionic emission.

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The performance of the planar magnetron sputtering apparatus with the use of a c-axis oriented single-domain Sm123 bulk superconductor with 60 mm in diameter is discussed. A high magnetic field of 4.2 T at the surface of the superconductor coupled with a high electric field of maximum 6 kV enabled us to discharge even at the Ar gas pressure of 1 × 10−3 Pa. A target-to-substrate distance could be extended to 30 mm under low pressures of 10−2–10−3 Pa to allow the deposition with an incidence angle normal to a substrate. The discharging characteristics of Cu, Ni, Fe, Al and carbon targets in the pressure range over 10−1 to 10−3 Pa were studied under different target voltages. The deposition rates of 0.063 nm s−1 (or 38 Å min−1) and 0.013 nm s−1 (or 8 Å min−1) were achieved for Cu and Fe targets with 3 mm in thickness, respectively, under the Ar pressure of 6.6 × 10−2 Pa.