Low Resistivity Contacts to Superconducting Oxide Using Ag2O Powder

Low resistivity contacts to the bulk specimens of YBa2Cu3O7-y with Ag have been developed. In order to obtain homogeneous mixtures of YBa2Cu3O7-y and Ag we used Ag2O powder, The contact resistivity of 0.19μΩ·cm2 was obtained by annealing the specimen at 1, 100°C. The current versus voltage characteristic of the contact was found to be ohmic. The contact was made to the specimen which is exposed to air for 110 days; the contact resistivity after this period had elapsed was almost the same as the contact made to the fresh specimen. Using physical and chemical analysis it was found that all the Ag2O in YBa2Cu3O7-y was separated to Ag and that Ag existed in all voids.