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

Missert, Nancy; Brunke, Lyle; Henry, Michael D.; Wolfley, Steve; Howell, Steve; Mudrick, John; Lewis, Rupert

doi:10.1109/tasc.2017.2669582

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

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Abstract

We investigated properties of NbN and Ta_xN 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 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 N₂ 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:

^[1]; Brunke, Lyle ^[1]; Henry, Michael D. ^[1]; Wolfley, Steve ^[1]; Howell, Steve ^[1]; Mudrick, John ^[1]; Lewis, Rupert ^[1]

Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

Publication Date:: Wed Feb 15 00:00:00 EST 2017

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:: 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

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                    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.

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                    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.  https://doi.org/10.1109/tasc.2017.2669582

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                    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.  https://doi.org/10.1109/tasc.2017.2669582.  https://www.osti.gov/servlets/purl/1356859.

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@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}

}

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

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