Gallium Oxide Nanostructures for High Temperature Sensors

Chintalapalle, Ramana V.

doi:10.2172/1261782

Title: Gallium Oxide Nanostructures for High Temperature Sensors

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Abstract

Gallium oxide (Ga₂O₃) thin films were produced by sputter deposition by varying the substrate temperature (T_s) in a wide range (T_s=25-800 °C). The structural characteristics and electronic properties of Ga₂O₃ films were evaluated using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDS), Rutherford backscattering spectrometry (RBS) and spectrophotometric measurements. The effect of growth temperature is significant on the chemistry, crystal structure and morphology of Ga₂O₃ films. XRD and SEM analyses indicate that the Ga₂O₃ films grown at lower temperatures were amorphous while those grown at T_s≥500 oC were nanocrystalline. RBS measurements indicate the well-maintained stoichiometry of Ga₂O₃ films at T_s=300-800 °C. The electronic structure determination indicated that the nanocrystalline Ga₂O₃films exhibit a band gap of ~5 eV. Tungsten (W) incorporated Ga₂O₃ films were produced by co-sputter deposition. W-concentration was varied by the applied sputtering-power. No secondary phase formation was observed in W-incorporated Ga₂O₃ films. W-induced effects were significant on the structure and electronic properties of Ga2O3 films. The band gap of Ga₂O₃ films without W-incorporation was ~5 eV. Oxygen sensor characteristics evaluated using optical and electrical methods indicate a faster response in W-doped Ga₂O₃ films compared to intrinsic Ga₂O₃ films. The results demonstrate the applicability of bothmore »« less

Authors:

Chintalapalle, Ramana V. ^[1]

Univ. of Texas, El Paso, TX (United States)

Publication Date:: Thu Apr 30 00:00:00 EDT 2015

Research Org.:: Univ. of Texas at El Paso, TX (United States)

Sponsoring Org.:: USDOE

OSTI Identifier:: 1261782

DOE Contract Number:: FE0007225

Resource Type:: Technical Report

Country of Publication:: United States

Language:: English

Subject:: 47 OTHER INSTRUMENTATION

Citation Formats


                    Chintalapalle, Ramana V. Gallium Oxide Nanostructures for High Temperature Sensors.  United States: N. p., 2015. 
        Web.  doi:10.2172/1261782.

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                    Chintalapalle, Ramana V. Gallium Oxide Nanostructures for High Temperature Sensors.  United States.  https://doi.org/10.2172/1261782

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                    Chintalapalle, Ramana V. 2015.  
        "Gallium Oxide Nanostructures for High Temperature Sensors".  United States.  https://doi.org/10.2172/1261782.  https://www.osti.gov/servlets/purl/1261782.

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@article{osti_1261782,

  title        = {Gallium Oxide Nanostructures for High Temperature Sensors},

  author       = {Chintalapalle, Ramana V.},

  abstractNote = {Gallium oxide (Ga2O3) thin films were produced by sputter deposition by varying the substrate temperature (Ts) in a wide range (Ts=25-800 °C). The structural characteristics and electronic properties of Ga2O3 films were evaluated using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDS), Rutherford backscattering spectrometry (RBS) and spectrophotometric measurements. The effect of growth temperature is significant on the chemistry, crystal structure and morphology of Ga2O3 films. XRD and SEM analyses indicate that the Ga2O3 films grown at lower temperatures were amorphous while those grown at Ts≥500 oC were nanocrystalline. RBS measurements indicate the well-maintained stoichiometry of Ga2O3 films at Ts=300-800 °C. The electronic structure determination indicated that the nanocrystalline Ga2O3films exhibit a band gap of ~5 eV. Tungsten (W) incorporated Ga2O3 films were produced by co-sputter deposition. W-concentration was varied by the applied sputtering-power. No secondary phase formation was observed in W-incorporated Ga2O3 films. W-induced effects were significant on the structure and electronic properties of Ga2O3 films. The band gap of Ga2O3 films without W-incorporation was ~5 eV. Oxygen sensor characteristics evaluated using optical and electrical methods indicate a faster response in W-doped Ga2O3 films compared to intrinsic Ga2O3 films. The results demonstrate the applicability of both intrinsic and W-doped Ga-oxide films for oxygen sensor application at temperatures ≥700 °C.},

  doi          = {10.2172/1261782},

  url          = {https://www.osti.gov/biblio/1261782},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Thu Apr 30 00:00:00 EDT 2015},

  month        = {Thu Apr 30 00:00:00 EDT 2015}

}

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