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Title: Materials Study of NbN and Ta x N Thin Films for SNS Josephson Junctions

Abstract

We investigated properties of NbN and Ta xN thin films grown at ambient temperatures on SiO 2/Si substrates by reactive-pulsed laser deposition and reactive magnetron sputtering (MS) as a function of N 2 gas flow. Both techniques produced films with smooth surfaces, where the surface roughness did not depend on the N 2 gas flow during growth. High crystalline quality, (111) oriented NbN films with T c up to 11 K were produced by both techniques for N contents near 50%. The low temperature transport properties of the Ta xN films depended upon both the N 2 partial pressure used during growth and the film thickness. Furthermore, the root mean square surface roughness of Ta xN films grown by MS increased as the film thickness decreased down to 10 nm.

Authors:
ORCiD logo [1];  [1];  [1];  [1];  [1];  [1];  [1]
  1. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Publication Date:
Research Org.:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA)
OSTI Identifier:
1356859
Report Number(s):
SAND2017-4568J
Journal ID: ISSN 1051-8223; 652916; TRN: US1702156
Grant/Contract Number:
AC04-94AL85000
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
IEEE Transactions on Applied Superconductivity
Additional Journal Information:
Journal Volume: 27; Journal Issue: 4; Journal ID: ISSN 1051-8223
Publisher:
Institute of Electrical and Electronics Engineers (IEEE)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; atomic force microscopy; electronic transport; NbN; TaN; superconducting materials; scanning electron microscopy; x-ray diffraction

Citation Formats

Missert, Nancy, Brunke, Lyle, Henry, Michael D., Wolfley, Steve, Howell, Steve, Mudrick, John, and Lewis, Rupert. Materials Study of NbN and Ta x N Thin Films for SNS Josephson Junctions. United States: N. p., 2017. Web. doi:10.1109/tasc.2017.2669582.
Missert, Nancy, Brunke, Lyle, Henry, Michael D., Wolfley, Steve, Howell, Steve, Mudrick, John, & Lewis, Rupert. Materials Study of NbN and Ta x N Thin Films for SNS Josephson Junctions. United States. doi:10.1109/tasc.2017.2669582.
Missert, Nancy, Brunke, Lyle, Henry, Michael D., Wolfley, Steve, Howell, Steve, Mudrick, John, and Lewis, Rupert. Wed . "Materials Study of NbN and Ta x N Thin Films for SNS Josephson Junctions". United States. doi:10.1109/tasc.2017.2669582. https://www.osti.gov/servlets/purl/1356859.
@article{osti_1356859,
title = {Materials Study of NbN and Ta x N Thin Films for SNS Josephson Junctions},
author = {Missert, Nancy and Brunke, Lyle and Henry, Michael D. and Wolfley, Steve and Howell, Steve and Mudrick, John and Lewis, Rupert},
abstractNote = {We investigated properties of NbN and TaxN thin films grown at ambient temperatures on SiO2/Si substrates by reactive-pulsed laser deposition and reactive magnetron sputtering (MS) as a function of N2 gas flow. Both techniques produced films with smooth surfaces, where the surface roughness did not depend on the N2 gas flow during growth. High crystalline quality, (111) oriented NbN films with Tc up to 11 K were produced by both techniques for N contents near 50%. The low temperature transport properties of the TaxN films depended upon both the N2 partial pressure used during growth and the film thickness. Furthermore, the root mean square surface roughness of TaxN films grown by MS increased as the film thickness decreased down to 10 nm.},
doi = {10.1109/tasc.2017.2669582},
journal = {IEEE Transactions on Applied Superconductivity},
number = 4,
volume = 27,
place = {United States},
year = {Wed Feb 15 00:00:00 EST 2017},
month = {Wed Feb 15 00:00:00 EST 2017}
}

Journal Article:
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