Structural, optical and electrical properties of undoped polycrystalline hematite thin films produced using filtered arc deposition
| Autor: | Phil J. Martin, Julie Glasscock, I. C. Plumb, Piers R. F. Barnes, Avi Bendavid |
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| Rok vydání: | 2008 |
| Předmět: |
Materials science
business.industry Band gap Metals and Alloys Analytical chemistry Surfaces and Interfaces Activation energy Hematite Arrhenius plot Surfaces Coatings and Films Electronic Optical and Magnetic Materials Optics Electrical resistivity and conductivity Physical vapor deposition visual_art Materials Chemistry visual_art.visual_art_medium Direct and indirect band gaps Thin film business |
| Zdroj: | Thin Solid Films. 516:1716-1724 |
| ISSN: | 0040-6090 |
| Popis: | Thin films of α -Fe 2 O 3 (hematite) were deposited using filtered arc deposition. The structural, optical and electrical properties of the films have been characterized. High-purity hematite films were produced, free from other iron oxide phases and impurities. The films exhibit preferred orientation, with the c-axis of the hexagonal structure aligned perpendicular to the substrate. The films have an upper uncertainty bound of the porosity of 15%, with a microindentation hardness of 17.5 ± 1 GPa and elastic modulus of 1235 ± 5 GPa. The indirect and direct band gap energies were found to be approximately 1.9 eV and 2.7 eV, respectively. The refractive index, and the extinction and absorption coefficients were determined from total reflectance and direct transmittance measurements. The thin films exhibit a high resistivity (≥ 10 5 Ω cm) which indicates pure α -Fe 2 O 3 . An activation energy of 0.7 eV was calculated from an Arrhenius plot of the conductivity. |
| Databáze: | OpenAIRE |
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