| abstract |
Provided is a composition for forming a resist underlayer film, the composition exhibiting strong etching resistance, having a good dry etching rate ratio and a good optical constant, and being capable of forming a film that provides good coverage over a so-called multilevel substrate and that is flat with reduced difference in thickness after embedding. Also provided are: a resist underlayer film that uses said composition for forming a resist underlayer film; and a method for producing a semiconductor device. The composition for forming a resist underlayer film contains: a polymer having the partial structure represented by formula (1); and a solvent. (In the formula, Ar represents an optionally substituted C6-20 aromatic group.) |