Oxidation of SiC

✍ Scribed by J. Li; P. Eveno; A. M. Huntz

• Book ID: 102937444
• Publisher: John Wiley and Sons
• Year: 1990
• Tongue: German
• Weight: 909 KB
• Volume: 41
• Category: Article
• ISSN: 0947-5117
• DOI: 10.1002/maco.19900411212

✦ Synopsis

Abstract

The oxidation behaviour of SiC monocrystalline and polycrystalline samples differing by their structure and the impurity content, was studied in O~2~, in air and in O~2~ + H~2~O atmospheres, between 1050 and 1400°C.

Classical techniques for determining the oxidation kinetics and for analyzing the morphology, the nature and the composition of the scales were used. In order to determine the oxidation mechanism, complementary tests were also made: they mainly consisted in successive oxidations in ^16^O~2~, ^18^O~2~, or ^29^Si and ^13^C implantations, followed by SIMS analyses.

It was shown that the SiO~2~ scale growth is controlled by lattice oxygen diffusion, the defect responsible for the oxygen diffusion are oxygen vacancies. Carbon in the silica scale is in an elementary form (C‐C bonds), and neither CO or SiO outward diffusion are a rate controlling process for the scale growth. Bubbles on the outer surface of the scale are due to the presence of boron.