Abstract
Double oxidation of SiC single crystal was carried out in oxidizing gas (O2 or H2O) at 1673 K first and then in isotopic water (H218O or D2O) at 1473 K or 1573 K to trace diffusing species during oxidation at high temperatures. SIMS analysis revealed that deuterium was enriched near SiO2/SiC interface when SiC was oxidized in Ar/D2O gas mixture at the second oxidation step, indicating that water molecules or hydroxyls diffused in SiO2 layer to the SiO2/SiC interface. Large amount of carbon in SiO2 scale near the SiO2/SiC interface after oxidation in dry Ar/O 2 gas mixture suggests a possibility that outward diffusion of carbonaceous species can be rate-controlling step during oxidation in dry Ar/O2 atmosphere. Decrease in the amount of the carbon with oxidation time in Ar/H218O gas mixture at the second oxidation step implies that the outward diffusion of carbon-aceous species in SiO2 scale was promoted during oxidation in atmosphere containing water vapor.
Original language | English |
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Pages (from-to) | 960-964 |
Number of pages | 5 |
Journal | Journal of the Ceramic Society of Japan |
Volume | 116 |
Issue number | 1357 |
DOIs | |
Publication status | Published - 2008 Sept |
Externally published | Yes |
Keywords
- Diffusion
- Isotope
- Oxidation
- SIMS
- Silica
- Silicon carbide
- Water
ASJC Scopus subject areas
- Ceramics and Composites
- Chemistry(all)
- Condensed Matter Physics
- Materials Chemistry