TICABACUO HIGH-TC SUPERCONDUCTING MICROSTRIP RING RESONATORS DESIGNEDFOR 12 GHZ

Microwave properties of sputtered Tl-Ca-Ba-Cu-O thin films were invest igated by designing, fabricating and testing microstrip ring resonator s. Ring resonators designed for 12 GHz fundamental resonance frequency , were fabricated and tested. From the unloaded Q values for the reson ators, the surface resistance was calculated by separating the conduct or losses from the total losses. The penetration depth was obtained fr om the temperature dependence of resonance frequency, assuming that th e shift in resonance frequency is mainly due to the temperature depend ence of penetration depth. The effective surface resistance at 12 GHz and 77 K was determined to be between 1.5 and 2.75 mOMEGA, almost an o rder lower than Cu at the same temperature and frequency. The effectiv e penetration depth at 0-degrees-K is approximately 7000 angstrom.