摘要 |
During the preparation of a Josephson junction device, one of the steps for making a base electrode is to deposit a superconducting material on a substrate and to anneal the deposited material to make it a continuous homogeneous polycrystalline grain-like electrode material. Ordinarily, the base electrode and the counter electrode materials are deposited in a vacuum system at a vacuum pressure which is below onex10-6 torr to remove all contaminants such as oxygen, oxides of carbon and water vapor. It has been discovered that depositing conventional superconducting base electrode and counter electrode materials in the presence of an inert gas at much high vacuum pressures around 20x10-3 torr produce a superior lead-gold superconductive electrode which is substantially immune to thermal cycling.
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