High-T/sub c/ superconducting microstrip resonators and filters on LaAlO/sub 3/

The authors discuss recent developments in high-Q microstrip resonators and filters using various deposition processes. They successfully developed sputtering, metalorganic vapor deposition (MOCVD), and laser deposition processes that produces high-quality high-T/sub c/ superconducting (HTS) films on LaAlO/sub 3/. For the double-sided MOCVD process, replacing the Ag ground plane with an HTS ground plane in silver ground plane eliminates extra surface losses due to normal metal ground conductors. These two-sided microwave circuits yield higher microwave performances than one-sided HTS circuits and much higher performance than identical Ag circuits. HTS surface resistances less than 330 mu Omega at 10 GHz were achieved. Q-values of 9600 at 1.3 GHz were achieved in meanderline resonators. >