TRANSPORT-PROPERTIES OF YBA2CU3O7-DELTA Y0.3PR0.7BA2CU3O7-DELTA/YBA2CU3O7-DELTA JOSEPHSON-JUNCTIONS/

u3O7-delta/Y0.3Pr0.7Ba2Cu3O7-delta/YBa2Cu3O7-delta Josephson junctions have been prepared by a multistep laser ablation process using an imp roved shadow mask technique. Junctions with barrier layer thicknesses larger than 12 nm exhibit current-voltage characteristics which are cl ose to those predicted by the resistively shunted junction (RSJ) model . Under microwave irradiation, clear Shapiro steps, which could be wel l described by the RSJ model, occur in the current-voltage curves. Fro m the exponential decrease of the critical current density with increa sing barrier layer thickness, an order parameter decay length xi(n) of 21 +/- 4 nm at T = 4.2 K has been determined for Y0.3Pr0.7Ba2Cu3O7-de lta. The increase of the junction resistance with decreasing temperatu re indicates that the barrier layer dominates the junction properties.