{
  "abstract": "Tantalum thin films are used in low-loss superconducting quantum circuits, yet the growth conditions governing selection of $α$-Ta(110), $α$-Ta(111), and metastable $β$-Ta on c-plane sapphire remain uncertain. We deposited 100 nm Ta films by dc magnetron sputtering on Al$_2$O$_3$(0001) at 300-900 $^\\circ$C while varying the O$_2$ partial pressure from a $5.5\\times10^{-11}$ Torr ultrahigh-vacuum baseline to $2.23\\times10^{-4}$ Torr. Absorption-corrected X-ray diffraction texture coefficients were used to construct a ternary phase-orientation growth map in terms of temperature and the oxygen-to-Ta impingement flux ratio ($2Φ_{O_2}/Φ_{Ta}\\leq4.8\\times10^{-6}$ to 19). Without added oxygen, $α$-Ta(110) dominated at every temperature. At an O$_2$ pressure of only $2.5\\times10^{-9}$ Torr ($2Φ_{O_2}/Φ_{Ta}=2.2\\times10^{-4}$), $α$-Ta(111) accounted for 98-99% of the normalized texture weight from 300 to 700 $^\\circ$C, decreasing to 65% at 900 $^\\circ$C. Substantial $β$-Ta formed only at the highest oxygen dose, dominating at 300 $^\\circ$C and disappearing at 900 $^\\circ$C. The apparent $β$(001)/$α$(110) selection energy of $1.07\\pm0.16$ eV is comparable to the activation energy for oxygen diffusion in Ta, consistent with oxygen transport influencing phase selection. Oxygen also produced orientation-dependent changes in crystallite size and microstrain. These findings establish oxygen-controlled processing windows for phase- and orientation-selective growth of Ta films for superconducting devices.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.35768",
  "author_total": 4,
  "authors": [
    {
      "name": "Marius O. Eji"
    },
    {
      "name": "Tyler J. Kirkpatrick"
    },
    {
      "name": "Ty J. Cawein"
    },
    {
      "name": "Joseph P. Corbett"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/3351px5148th1.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.35768",
  "fulltext_url": null,
  "id": "3351px5148th1",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.35768",
  "language": null,
  "licence": "LicenseRef-arXiv-nonexclusive-1.0",
  "licence_label": "arXiv licence",
  "licence_source": "article",
  "licence_url": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "cond-mat.mtrl-sci"
    ],
    [
      "arxiv",
      "cond-mat.supr-con"
    ],
    [
      "arxiv",
      "quant-ph"
    ],
    [
      "openalex",
      "3107|Surface and Thin Film Phenomena"
    ]
  ],
  "openalex": "W7223816135",
  "pdf_url": "https://arxiv.org/pdf/2610.35768",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-26",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/3351px5148th1.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:35:35Z",
      "native_id": "2610.35768",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.35768"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.mtrl-sci",
      "subfield": "condensed-matter"
    },
    {
      "field": "physics",
      "origin": "arxiv:quant-ph",
      "subfield": "quantum"
    }
  ],
  "title": "Growth Phase Map of α and \\b{eta} Tantalum as a Function of Growth Temperature and Oxygen Partial Pressure",
  "title_text": "Growth Phase Map of α and \\b{eta} Tantalum as a Function of Growth Temperature and Oxygen Partial Pressure",
  "type": "preprint",
  "updated_at": "2026-10-30T12:35:35Z",
  "url": "https://research.draconitic.com/paper/3351px5148th1",
  "venue": "arXiv",
  "versions": []
}