A polyphenylcarbosilane (PPCS) precursor was heated under an oxidizing atmosphere to form a silicon dioxide thin film, although the PPCS precursor coated on silicon carbide fiber is usually heated under a reducing atmosphere for high strength ceramics. The PPCS phase decomposed and then recombined with numerous oxygen and phenyl groups. Finally, it was converted from hybrid to inorganic material in a temperature range of 400 degrees C to 550 degrees C under an oxidizing atmosphere. Based on our results, the PPCS precursor can be changed into silicon dioxide via heat treatment under an oxidizing atmosphere, and can serve as an alternative to SiO(2) for high performance electric devices. (C) 2011 Elsevier B.V. All rights reserved.