Selection of the best proper DC-SQUIDs in a Multi-SQUID configuration

Applied Superconductivity Conference 2006 -- AUG 27-SEP 01, 2006 -- Seattle, WAWOS: 000248442200142We have carried out experimental investigation of multi-DC-SQUID magnetometer configuration fabricated on YBa2Cu3O7-delta thin films onto 24 degree SrTiO3 bicrystal substrates by directly coupling the pick-up loop to DC-SQUIDs. The layout of the magnetometer pick-up loop was chosen as a square washer configuration by maximizing. loop effective area and minimizing loop inductance. We have used Dc-Magnetron Sputtering technique for deposition of the films and chemical etching process for patterning the Josephson junctions having 4 mu m widths. The use of multi-SQUID configuration is related to the selection of the best proper junctions for SQUID to improve the chip sensitivity with selectivity option of choosing the squid junctions rather than multichannel operation. Selection of the best junctions compared to each other depending on the junction critical currents and noise levels caused by the fabrication process and placements of the junctions on the grain boundary enable having an increased output signal of the DC-SQUID.Amer Superconductor Corp, Univ Wiscosin-Madison, Appl Superconduct Ctr, Florida State Univ, Field Lab, Appl Superconduct Conf Inc, AYI WAH ChANG, Boeing Co, CCAS, Coalit Commercial Applicat Superconductors, Cryogen Ltd, Univ Cambridge, Dept Mat Sci & Metallurgy, Device Mat Grp, GE Global Res Ctr, Electromagnet & Superconduct Lab, IEEE Coucil Superconduct, Univ Cambridge, IRC Superconduct, Oxford Instruments, Superconductor Sci & Technol, Inst Phys Publ, SuperPower Inc, Univ Houston, TcSU