Improvement of thermal stability and critical current of superconducting Nb multi-layer wiring

Keiji Tsukada, Jun Kawai, Hisashi Kado

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

A spiral coil of double-Nb layers is fabricated to investigate the thermal degradation mechanism of Nb multi-layer wiring. The superconductivity of the coil with a sputtered SiO2 insulation layer easily deteriorates as a result of surface oxidation where the step coverage is incomplete. Higher critical current and thermal stability are obtained by a combination of planarization using spin-coated SiO2 for the insulation between Nb wiring, surface nitridation of Nb, and taper etching of the contact hole. The critical current of the coil with a spin-coated SiO2 film is about twice that of a coil with sputtered SiO2; even though it was baked at 300°C for 30 min for each layer.

Original languageEnglish
JournalJapanese Journal of Applied Physics, Part 2: Letters
Volume32
Issue number12 B
Publication statusPublished - 1993
Externally publishedYes

Fingerprint

wiring
Critical currents
Electric wiring
Insulation
critical current
Thermodynamic stability
thermal stability
coils
Nitridation
Superconductivity
insulation
Etching
Pyrolysis
Oxidation
thermal degradation
tapering
electric contacts
superconductivity
etching
oxidation

ASJC Scopus subject areas

  • Physics and Astronomy (miscellaneous)

Cite this

Improvement of thermal stability and critical current of superconducting Nb multi-layer wiring. / Tsukada, Keiji; Kawai, Jun; Kado, Hisashi.

In: Japanese Journal of Applied Physics, Part 2: Letters, Vol. 32, No. 12 B, 1993.

Research output: Contribution to journalArticle

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