A study was made on Nb based Josephson junctions with evaporated Te barriers. As the first step, a Nb-Te-Pb configuration was tested. The smooth surfaced Nb electrode enabled the formation of a pinhole free barrier. Supercurrent density was found to be large compared to that for surface oxidized junctions. As the second step, a Nb-Te-Nb structure was tested. Although the junction uniformity was not as good as that of the Nb-Te-Pb junctions, the aging property was drastically improved. Considerations were made on the origin of the remaining aging. The junctions showed excellent response to 50 GHz signals.
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