A via-filling material includes a polymer containing a repeating unit represented by ##STR00001## wherein R.sub.1 one of hydrogen, fluorine, chlorine, bromine, and methyl group; R.sub.2 is one of hydrogen, a C.sub.1-3 alkyl group, and a C.sub.1-4 alkyl group in which the hydrogen is replaced by at least one of fluorine, chlorine, and bromine; and X is --C(.dbd.O)O-- or --S(.dbd.O).sub.2O--. This via-filling material does not generate deposits around an opening of a via hole during plasma etching and provides a semiconductor integrated circuit with high reliability, even when a trench wider than the via hole is formed by plasma etching around the via hole filled with the via-filling material.
