Chemical-Vapor Deposition of OH-free and Low-k Organic-Silica Films

A new sourcegas has been presented for quasi hydrogen-free chemical-vapor deposition of organic-silica films. The content of the methyl groups incorporated in the film was as much as 25% of that of Si, and the as-deposited film contained only a few silanol and cyanate groups. Thus it had good insulating characteristics with a dielectric constant, k, as low as 3.5 even under as-deposited conditions. These characterisitcs were further improved by vacuum annealing. And, the value of k became became 3.0 with a low-field resistivity of more than 1015 Ωcm, after 500°C annealing.