THIN POLYIMIDE PROTECTIVE COATING FOR HTS-THIN FILM DEVICES

To protect the HTS-thin film microwave-frequency passive and active de vices from traces of acids and humidity in the atmosphere, the oxide s uperconductors must be passivated. Electric parameters of the films an d Q-factor of tile resonators have been measured before and after pass ivation cycle, and thermocycles. The relative decrease of the critical current density for different quality HTS films after passivation tre atment is explained by water penetration between grains during imidiza tion cycle.