STUDY OF IN-SITU PREPARED HIGH-TEMPERATURE SUPERCONDUCTING EDGE-TYPE JOSEPHSON-JUNCTIONS

High-T-c edge-type Josephson junctions usually have ex-situ interfaces , that probably contain damaged layers caused by etching process and/o r by exposure to air. The ex-situ interface layer may be an origin of poor reproducibility and uniformity of the device characteristics, as well as an excess interface resistance and a suppression of the critic al current. We have developed an insitu edge preparation process to im prove the uniformity and electrical characteristics of the edge juncti ons. In our in-situ process, the base YBaCuO electrode edge is not exp osed to air after the preparation of the edge and subsequently followe d by the deposition of a barrier layer and a counter electrode. The in -situ YBaCuO/PrBaCuO/YBaCuO junctions showed larger critical current d ensity (J(c)) and normal state conductance (G(n)) than the ex-situ jun ctions. In addition, smaller J(c) and G(n) spreads have been obtained for the in-situ junctions.