Abstract: A method for forming a silicone polymer insulation film having a low dielectric constant, high thermal stability, high humidity-resistance, and high O2 plasma resistance on a semiconductor substrate is applied to a plasma CVD apparatus. The first step is introducing a silicon-containing hydrocarbon compound expressed by the general formula Si&agr;O&agr;−1(R)2&agr;−&bgr;+2(OCnH2n+1)&bgr; (&agr;, &bgr;, x, and y are integers) and then introducing the vaporized compound to the reaction chamber of the plasma CVD apparatus. The residence time of the material gas is lengthened by, for example, reducing the total flow of the reaction gas, in such a way as to form a silicone polymer film having a micropore porous structure with a low dielectric constant.

Abstract: A method for forming a silicone polymer insulation film having a low relative dielectric constant, high thermal stability and high humidity-resistance on a semiconductor substrate is applied to a plasma CVD apparatus. The first step is introducing a silicon-containing hydrocarbon compound expressed by the general formula Si&agr;O&bgr;CxHy (&agr;, &bgr;, x, and y are integers) to the reaction chamber of the plasma CVD apparatus. The silicon-containing hydrocarbon compound has at most two O—CnH2n+1 bonds and at least two hydrocarbon radicals bonded to the silicon. The residence time of the material gas is lengthened by, for example, reducing the total flow of the reaction gas, in such a way as to form a silicone polymer film having a micropore porous structure with a low relative dielectric constant.