Thermal Stability of Oxide Film Formed on SiC Nanri,

摘要

Cristobalite formed by oxidation of SiC at 1400 deg C for 3h in air showed the mass loss and degradation of the crystallinity by repeatedly heat-treatment in argon atmosphere at 1400 deg C. The tendency in the mass loss was different by its crystallinity. Samples with good crystallinity showed decreasing tendency like a quadratic curve. Though the amount of mass loss was small at the early stage of heat-treatment, it was large at the later stage. On the other hand, mass loss of the samples with poor crystallinity showed decreasing tendency in rectilinear. And the decreasing rate remained almost constant from early stage to later stage of heat-treatment. The main factor of this mass loss is attributed to be the volatile SiO formed by solid state reaction between SiC and SiO_2.