VERTICAL C-AXIS MICROBRIDGE JUNCTIONS IN YBA2CU3O7 PRBA2CU3O7 THIN-FILMS/

The fabrication and measurement of microbridge junctions in the vertic al c-axis direction of YBCO/PBCO/YBCO evaporated thin films is describ ed, Single junctions show critical current modulation with applied mag netic field, the period scaling with junction size, The IV characteris tics show Shapiro steps to high order when irradiated with microwaves. Initial measurements of linear arrays suggest that with further optim isation of the processing steps a reproducible junction technology cou ld emerge. Very low inductance (L approximate to 5-15pH) SQUIDs have b een demonstrated with dV/d Phi>1mV/Phi(0) at 50K, The vertical SQUID l oop geometry of these SQUIDs has allowed a direct determination of the penetration depth as a function of temperature.