| abstract |
[Problem] To increase the adhesiveness between a resist pattern formed on a resist underlayer film and the resist underlayer film and prevent the formation of an undercut profile in the resist pattern.n[Solution] An additive for a composition for forming a resist underlayer film, which comprises a polymer having a structural unit represented by formula (1); and a composition for forming a resist underlayer film for lithography, which comprises a resin binder, an organic solvent and the additive for a composition for forming a resist underlayer film.n(In the formula, R 1 represents a hydrogen atom or a methyl group; L represents a bivalent linking group; X represents an acyloxy group which has an amino group protected by a tert-butoxycarbonyl group or a nitrogenated heterocyclic ring protected by a tert-butoxycarbonyl group.) |