Thin film technology of high-critical-temperature superconducting electronics. Annual report 1 Aug 82-30 Oct 83

Technical Report · Mon Dec 05 04:00:00 EST 1983

OSTI ID:6830658

Talvacchio, J; Braginski, A I; Gavaler, J R; Janocko, M A; Manocha, A S

The objective of the first year's work was to investigate A15 superconductor/barrier oxide interfaces, identify oxide depth profiles, and determine resulting tunneling characteristics using soft tunnel junction counterelectrodes. Bilayers consisting of Nb and vanadium-silicon (A15) base electrodes and thin Y, Al, and Si barriers have been deposited in-situ and oxidized in humid air for up to three days. XPS analysis was used to compare the barrier coverage, uniformity, oxidation, and ability to protect the base electrode from oxidation for three deposition techniques: dc magnetron sputtering, dc diode sputtering, and reactive diode sputtering followed by pyrolysis. Y and Al have been found to be fully oxidized due to long oxidation times. In the above conditions the overlayers did not protect the superconductors from oxidation/hydration, and the surface of oxidized vanadium-silicon was also degraded by atomic segregation. The tunneling I-V characteristics exhibited very high leakage currents also suggestive of incomplete superconductor coverage by the metallic overlayer. Mo-Re was investigated for its potential as a high-critical-temperature counterelectrode. A very low oxidation rate was found indicating potential compatibility with yttrium hydroxide-sealed barriers. Low temperature growth (60 C) of MoRe (86 at. % Mo) with only a 5% decline in critical temperature has been demonstrated. Work will continue in a closed system to eliminate the base superconductor degradation, reduce leakage and study high-critical-temperature counterelectrodes.

• Research Organization: Westinghouse Electric Corp., Pittsburgh, PA (USA). Research and Development Center
• OSTI ID: 6830658
• Report Number(s): AD-A-136722/6
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420201* -- Engineering-- Cryogenic Equipment & Devices
420800 -- Engineering-- Electronic Circuits & Devices-- (-1989)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CHEMICAL REACTIONS
ELECTRODES
ELECTRONIC CIRCUITS
ELEMENTS
FABRICATION
FILMS
JOSEPHSON JUNCTIONS
JUNCTIONS
METALS
MOLYBDENUM
NIOBIUM
OXIDATION
SPECTROSCOPY
SPUTTERING
SUPERCONDUCTING DEVICES
SUPERCONDUCTING JUNCTIONS
SUPERCONDUCTORS
THIN FILMS
TRANSITION ELEMENTS
VANADIUM