No abstract

Microbridges and dc-SQUIDS were fabricated in lift-off technique from rf sputtered YBaCuO films on MgO single crystal substrates. Microwave measurements at 9GHz on microbridges and the magnetic field dependence of their critical current reveal wide bridge behavior up to temperatures near the maximum operating temperature of the bridge. Mostly a linear dependence of the critical current on the temperature is found, which is connected to high intrinsic l/f-noise if the bridge is constant current biased slightly above the critical current. In some bridges and dc-SQUIDS regimes with a temperature dependence proportional to (1-TIT)I.' are found. In this case the l/f noise level i s muck smaller and SQUID modulation can be follswed to about 65K.