High Critical Current Densities in Nb3Sn Films with Engineered Microstructures — Artificial Pinning Microstructures

  • D. R. Dietderich
  • M. Kelman
  • J. R. Litty
  • R. M. Scanlan
Part of the Advances in Cryogenic Engineering book series (ACRE, volume 44)

Abstract

Films with layers of Nb, Cu, and Sn have been fabricated to simulate a Nb3Sn bronze-type process. These Nb3Sn films have produced critical current densities greater than 1 × 106 A/cm2 at 4.2 K and 7.5 T. Niobium films doped with Y, Sc, Dy, Al2O3, and Ti have been deposited with e-beam co-evaporation onto 75 mm diameter Si wafers with a 100 nm SiO2 buffer layer. The Nb layer was followed by a layer of Cu and a layer of Sn to complete the bronze-type process. The films with the highest Jc had about 8 vol. % Sc and about 18 vol. % Al2O3. Characterization of the microstructure by TEM shows that these high Jc films contained high density of inclusions about 5 nm in size and that the grain size of the Nb3Sn is about 20–25 nm for samples heat treated at 700°C for up to eight hours.

Keywords

Coefficient Ofthermal Expansion Critical Current Density Undoped Film High Critical Current Density Wafer Processing 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

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Copyright information

© Springer Science+Business Media New York 1998

Authors and Affiliations

  • D. R. Dietderich
    • 1
  • M. Kelman
    • 1
  • J. R. Litty
    • 1
  • R. M. Scanlan
    • 1
  1. 1.Lawrence Berkeley National LaboratoryBerkeleyUSA

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