A simple technique for micromachining and its application to the fabrication of Nb based superconducting bridges are described. The technique is based on the use of oblique deposition of SiO film for the mask of anodization. By this technique variable thickness bridges with the length of about 0.1 to 1 μm have been successfully fabricated. Superconducting properties of a bridge with the length of about 0.3 μm are descrived. Zero voltage current is obserbed up to 7.2 K which is about 3 K above the critical temperature of thinned region of Nb film. Microwave induced steps on the V-I curve are also observed. The technique described in this paper is found to be suitable for the fabrication of variable thickness bridge type Josephson junctions.

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The surface coverage of Te deposits on the cleaved KBr surfaces irradiated by various electron beams has been studied by transmission electron microscopy. The surface coverage is improved effectively by the irradiation both before and during deposition. The effects of high energy electrons (500-1, 000 eV) are remarkable rather than that of low energy electrons (20-250 eV) in the range of irradiation density less than 10¹¹ electrons/cm²/s. The low energy electrons are also effective in the range from 10¹¹ to 10¹² electrons/cm²/s and a maximum value of the surface coverage is obtained at 10¹² electrons/cm²/s. The maximum value is independent of the incident electron energy. These phenomena can be explained by preferential nucleation sites which are produced by the electron irradiation.

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A noble method for preparing rhenium thin film on a permalloy substrate has been proposed.
Main processes of the method include melting pressed rhenium powders on a substrate by a pulsed Nd-YAG laser beam to form around 30 μm thick rhenium films, tightly bound to the substrate. Optimum conditions for the film preparation were examined by correlating both matrix structures and surface chemical purities with the laser irradiation parameters.
Although some difficulties are still remaining, the proposed laser heating will be usefull for preparing high temperature melting films on low temperature melting substrate materials.

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