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A copolymer of methyl methacrylate (MMA) and 3-triethoxysilylpropyl methacrylate (ESPMA) was proposed as a positive-working electron beam (EB) resist of a new type. It was found that it had 4–10 times the resistance of polymethylmethacrylate (PMMA) against CBrF3 plasma damage. The mechanism of etching Nb in reactive-ion-etching (RIE) was deciphered. Using the new EB resist and nanometer process technology, an all-Nb thin film microbridge was fabricated. It shows the a.c. Josephson effect, i.e. the Shapiro steps upto the 11th were observed under millimeter-wave (70 GHz) radiation. In addition the coherently working performance of the series array of these thin-film microbridges were observed definitively.

Experimental studies of an inductively coupled RF-excited CW-HCN laser have been carried out. A maximum output power of 160mW in CW at 337 μm has been obtained using a laser tube 1 m long and 55mm inner dia.

Single micro-contact type Josephson junctions and Josephson triodes composing of three micro-contact type junctions have been investigated with the purpose of its usage for the sensitive heterodyne mixing device. These devices have been fabricated by the self-alignment technology, and the experimental results for the properties for the fabricated devices were reported. It was especially shown that the fabricated triode has revealed some of the fundamental properties as the Josephson triode. Numerical calculations also have been carried out and were in agreement to some extent with the experimental results.