Chemical-vapor deposition of OH-free and low-k organic-silica films

A new source gas has been presented for quasi hydrogen-free chemical-vapor deposition of organic-silica films. The content of the methyl groups incorp orated in the film was as much as 25% of that of Si, and the as-deposited f ilm contained only a few silanol and cyanate groups. Thus it had good insul ating characteristics with a dielectric constant, k, as low as 3.5 even und er as-deposited conditions. These characterisitcs were further improved by vacuum annealing. And, the value of k became became 3.0 with a low-field re sistivity of more than 10(15) Ohm cm: after 500 degrees C annealing.