Extension of the bi-epitaxial Josephson junction process to various substrates

Journal Article · Mon Oct 21 04:00:00 EDT 1991 · Applied Physics Letters; (United States)

DOI:https://doi.org/10.1063/1.106411· OSTI ID:5197641

Char, K; Colclough, M S; Lee, L P; Zaharchuk, G ^[1]

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1. Conductus, Inc., 969 West Maude Avenue, Sunnyvale, California (USA)

We report an extension of the bi-epitaxial Josephson junction process that permits the use of a variety of substrate materials and allows junctions to be placed at any level of a multilayer structure. The new materials, SrTiO{sub 3}, MgO, and CeO{sub 2}, serve as a base layer, a seed layer, and a buffer layer, respectively, and replace Al{sub 2}O{sub 3}, MgO, and SrTiO{sub 3} in the original bi-epitaxial process. This new process offers much more flexibility in designing a circuit. Bi-epitaxial junctions made with the new set of materials show much improved electrical properties, especially at 77 K. We attribute the improved electrical characteristics to a better thermal expansion match between the substrate and the thin-film layers. Important junction properties such as critical currents and junction resistances are compared to other types of grain boundary junctions.

• OSTI ID: 5197641
• Journal Information: Applied Physics Letters; (United States), Journal Name: Applied Physics Letters; (United States) Vol. 59:17; ISSN APPLA; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

426001* -- Engineering-- Superconducting Devices & Circuits-- (1990-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALKALINE EARTH METAL COMPOUNDS
CERIUM COMPOUNDS
CERIUM OXIDES
CHALCOGENIDES
CRITICAL CURRENT
CRYSTAL STRUCTURE
CURRENTS
ELECTRIC CURRENTS
ELECTRICAL PROPERTIES
ELECTRONIC EQUIPMENT
EQUIPMENT
FABRICATION
FILMS
FLUXMETERS
GRAIN BOUNDARIES
JOSEPHSON JUNCTIONS
JUNCTIONS
LOW TEMPERATURE
MAGNESIUM COMPOUNDS
MAGNESIUM OXIDES
MEASURING INSTRUMENTS
MICROSTRUCTURE
MICROWAVE EQUIPMENT
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
RARE EARTH COMPOUNDS
SQUID DEVICES
STRONTIUM COMPOUNDS
STRONTIUM OXIDES
SUPERCONDUCTING DEVICES
SUPERCONDUCTING FILMS
SUPERCONDUCTING JUNCTIONS
TITANIUM COMPOUNDS
TITANIUM OXIDES
TRANSITION ELEMENT COMPOUNDS