Josephson junction and DC SQUID made from superconducting Y-Ba-Cu-O thick film

YBa/sub 2/Cu/sub 3/O/sub 7-x/ thick films were fabricated by the method of screen printing. A zero-resistance state was achieved at 90 K. The highest critical current density was about 150 A/cm/sup 2/ at 77 K. A bridge-type Josephson junction and DC SQUID (superconducting quantum interference device) were fabricated from thick films and operated at 77 K. The induced steps produced by the AC Josephson effect were observed on the I-V (current voltage) curve when microwave radiation was applied to the junction. The clear periodic patterns of a DC SQUID are observable at 77 K. Environmental protection and the stability of thick films and devices are discussed. >