A Fluorinated Organic-Silica Film with Extremely Low Dielectric Constant

A fluorinated organic-silica film was prepared by quasi hydrogen-free chemical-vapor deposition. The content of methyl groups and fluorine atoms incorporated in the film were as much as 43% and 9% of that of Si. The film had good insulating characteristics with the dielectric constant, k, of as low as 2.5 even under as-prepared conditions. They were improved by vacuum annealing; k was 2.1 and the low-field resistivity was 1016 Ωcm after annealing at 500°C. It was confirmed that the film prepared at 200°C was stable for more than 20 days in the air.