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Title: Gallium Oxide Nanostructures for High Temperature Sensors

Abstract

Gallium oxide (Ga 2O 3) 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 Ga 2O 3 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 Ga 2O 3 films. XRD and SEM analyses indicate that the Ga 2O 3 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 Ga 2O 3 films at T s=300-800 °C. The electronic structure determination indicated that the nanocrystalline Ga 2O 3films exhibit a band gap of ~5 eV. Tungsten (W) incorporated Ga 2O 3 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 Ga 2O 3 films. W-induced effects were significant on the structure and electronic properties of Ga2O3 films. The band gap of Ga 2O 3 films without W-incorporation was ~5 eV. Oxygen sensor characteristics evaluated using optical andmore » electrical methods indicate a faster response in W-doped Ga 2O 3 films compared to intrinsic Ga 2O 3 films. The results demonstrate the applicability of both intrinsic and W-doped Ga-oxide films for oxygen sensor application at temperatures ≥700 °C.« less

Authors:
 [1]
  1. Univ. of Texas, El Paso, TX (United States)
Publication Date:
Research Org.:
Univ. of Texas, 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.
Chintalapalle, Ramana V. Gallium Oxide Nanostructures for High Temperature Sensors. United States. doi:10.2172/1261782.
Chintalapalle, Ramana V. 2015. "Gallium Oxide Nanostructures for High Temperature Sensors". United States. doi:10.2172/1261782. https://www.osti.gov/servlets/purl/1261782.
@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},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2015,
month = 4
}

Technical Report:

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