Advertisement

Il Nuovo Cimento D

, Volume 19, Issue 8–9, pp 1375–1380 | Cite as

Superconductive thin-film devices for microwave applications

  • D. Andreone
  • L. Brunetti
  • V. Lacquaniti
  • S. Maggi
  • E. Monticone
  • R. Steni
Article
  • 28 Downloads

Summary

At IEN, two types of superconductive microwave sensors have been developed. Nb microbridge bolometers, working in the frequency range between 26 and 40 GHz, have been fabricated on polyimide substrates. For these devices we have measured a responsivity of 7 X 103 V/W. With a careful choice of device parameters, it is possible to achieve a noise equivalent power (NEP) of about 10-12 \(W/\sqrt {Hz} \), 3 orders of magnitude lower than that obtained with conventional bolometers. SIS mixers for radioastronomical observations at 94 GHz based on Nb/Al-AlOx/Nb Josephson tunnel junctions have been also realized. Josephson junctions, both single and two junctions stacks, have been fabricated using a SNAP process where liquid anodization is used not only for insulation and area patterning, but also for trimming the junction dimensions at a micrometer level. In order to use these junctions as SIS mixers for astrophysical observations at 94 GHz and possibly at higher frequencies, we have fabricated junctions with an area of a few square micrometer and current densities up to 104 A/cm2. The junctions are integrated with a low-pass filter made with a stripline technique, designed by means of a 3D electromagnetic simulator. The reflection coefficient of the filter has been evaluated to be 0.2 in the best case.

PACS 74.25

General properties correlations between physical properties in normal and superconducting states 

PACS 01.30.Cc

Conference proceedings 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. [1]
    Claeke J., Hoffer G. I., Richards P. L. andYeh N. H.,J. Appl. Phys.,48 (1977) 4865.CrossRefADSGoogle Scholar
  2. [2]
    Tucker J. R. andFeldman M. J.,Rev. Mod. Phys.,57 (1985) 1055.CrossRefADSGoogle Scholar
  3. [3]
    Lacquaniti V.,Monticone E. andSteni R.,inProceedings of the VII International Symposium IMEKO on Modern Electrical and Magnetic Measurement, Prague, 1995, Part I, pp. 38–41.Google Scholar
  4. [4]
    Pisani U., Rosso F. andBrunetti L.,Measurement,19 (1996) 21.CrossRefGoogle Scholar
  5. [5]
    Lacquaniti V., Maggi S., Monticone E. andSteni R.,IEEE Trans. Appl. Supercond.,6 (1996) 24.CrossRefGoogle Scholar

Copyright information

© Società Italiana di Fisica 1997

Authors and Affiliations

  • D. Andreone
    • 2
  • L. Brunetti
    • 2
  • V. Lacquaniti
    • 1
  • S. Maggi
    • 1
  • E. Monticone
    • 1
  • R. Steni
    • 1
  1. 1.Thin Film DepartmentIstituto Elettrotecnico Nazionale “G. Ferraris”TorinoItaly
  2. 2.Time and Frequency Metrology DepartmentIstituto Elettrotecnico Nazionale “G. Ferraris”TorinoItaly

Personalised recommendations