{
  "abstract": "Controlling heat flow in beta-gallium oxide (β-Ga2O3) thin films requires understanding both phonon transport within the semiconductor and heat transfer across metal/semiconductor interfaces. Here, we investigate these pathways in high-temperature radio-frequency magnetron-sputtered β-Ga2O3 films grown on c-plane sapphire with thicknesses from 0.42 to 2.1 μm. The thermal conductivity increases from 5.4–6.9 W m−1 K−1 in the 420 nm film to approximately 10–12 W m−1 K−1 in the thicker films. Structural characterization reveals thickness-dependent microstructural evolution, including grain coarsening and intergranular void-like defects. An analytical Debye–Klemens model incorporating phonon scattering from film boundary and defects reproduces the overall thickness dependence. The Ar plasma-treated samples exhibit Al/β-Ga2O3 thermal boundary conductance values of approximately 100 MW m−2 K−1, about 70% higher than the untreated sample (~60 MW m−2 K−1), while the thermal conductivity of the underlying films remains within a comparable range. Picosecond acoustic measurements, transmission electron microscopy and electron energy loss spectroscopy reveal a corresponding modification of the interfacial acoustic response and formation of an ultrathin amorphous/disordered near-surface region. Although variations between independent deposition runs cannot be excluded, these findings suggest that thickness-dependent microstructure and plasma-associated interface modifications offer promising approaches to tailoring thermal transport in β-Ga2O3-based devices.",
  "abstract_shown": true,
  "affiliations": [
    "Center for Energy and Advanced Materials Science, National Laboratory Astana, Astana 010000, Kazakhstan",
    "Department of Physics, School of Sciences and Humanities, Nazarbayev University, Astana 010000, Kazakhstan",
    "Institute of New Materials and Energy Technologies, 53 Kabanbay Batyr Ave., 010000 Astana, Kazakhstan",
    "Department of Physical Electronics, Faculty of Physics and Technology, Dagestan State University, Makhachkala 367000, Russia",
    "Centre for HRTEM, Nelson Mandela University, Port Elizabeth 6001, South Africa"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 7,
  "authors": [
    {
      "affs": [
        0,
        1,
        2
      ],
      "name": "Azat Abdullaev",
      "orcid": "0000-0001-8603-0937"
    },
    {
      "affs": [
        0,
        1,
        2
      ],
      "name": "Rustem Tlegenov",
      "orcid": "0009-0003-7251-4473"
    },
    {
      "affs": [
        3
      ],
      "name": "Magomed A. Umakhanov",
      "orcid": "0009-0001-7280-6340"
    },
    {
      "affs": [
        4
      ],
      "name": "Jacques O’Connell",
      "orcid": "0000-0002-3758-3997"
    },
    {
      "affs": [
        3
      ],
      "name": "Abubakar M. Ismailov",
      "orcid": "0000-0001-6834-0560"
    },
    {
      "affs": [
        0,
        1,
        2
      ],
      "name": "Kairolla Sekerbayev",
      "orcid": "0000-0001-6376-9851"
    },
    {
      "affs": [
        1
      ],
      "name": "Zhandos N. Utegulov",
      "orcid": "0000-0002-7574-9070"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/a9ads31b611ct.bib",
  "cited_by": 0,
  "doi": "10.3390/nano16211439",
  "fulltext_url": null,
  "id": "a9ads31b611ct",
  "issns": [
    "2079-4991"
  ],
  "landing_url": "https://www.mdpi.com/2079-4991/16/21/1439",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [],
  "openalex": null,
  "pdf_url": null,
  "pmcid": null,
  "pmid": null,
  "published": "2026-11-06",
  "publisher": "MDPI AG",
  "ris": "https://research.draconitic.com/paper/a9ads31b611ct.ris",
  "sources": [
    {
      "first_seen": "2026-11-10T00:21:23Z",
      "native_id": "10.3390/nano16211439",
      "source": "crossref",
      "url": "https://www.mdpi.com/2079-4991/16/21/1439"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "issn:2079-4991",
      "subfield": "materials-polymers"
    }
  ],
  "title": "Tuning Thermal Transport in Radio-Frequency-Sputtered Beta-Gallium Oxide Through Thickness and Plasma-Induced Interface Modification",
  "title_text": "Tuning Thermal Transport in Radio-Frequency-Sputtered Beta-Gallium Oxide Through Thickness and Plasma-Induced Interface Modification",
  "type": "peer-reviewed",
  "updated_at": "2026-11-10T00:21:23Z",
  "url": "https://research.draconitic.com/paper/a9ads31b611ct",
  "venue": "Nanomaterials",
  "versions": []
}