J. Phys. IV France 08 (1998) Pr3-297-Pr3-300
Application of silicon substrates for high-Tc Josephson junctions and SQUIDsS. Linzen, Y.J. Tian, U. Hübner, F. Schmidl, J. Scherbel and P. Seidel
Institut für Festkörperphysik, Friedrich-Schiller-Universität Jena, Lessingstrasse 8, 07743 Jena, Germany
We investigated the realization of YBCO Josephson junctions and SQUIDs on 10x10 mm2 silicon bicrystal substrates and on 2 inch single crystalline silicon wafers. All buffer layers, YBCO films, passivation and metallization layers were deposited with the laser ablation technique. Bicrystal junctions with RSJ-like I-V characteristics, ICRN products of 150 µV at 77 K and microwave response up to the THz range were realized. DC-SQUIDs consisting of these junctions have working temperatures up to 80 K and transfer functions up to 30 µV/Φ0; at 77 K. Further we enlarge our standard preparation technique of Josephson step-edge junctions on 5x10 mm2 to 2 inch silicon wafers. YBCO films of this size have a critical temperature Tc > 87 K and critical current densities jc (77K) > 3-106 A/cm2 over the whole wafer area.
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