RESIST UNDERLAYER FILM FORMING COMPOSITION CONTAINING PYRROLE NOVOLAC RESIN

摘要

[Problem] To provide an excellent resist underlayer film which has a dry etching rate selectivity close to that of a resist, a dry etching rate selectivity lower than that of a resist, or a dry etching rate selectivity lower than that of a semiconductor substrate. [Solution] A resist underlayer film forming composition which contains a polymer that has a unit structure represented by formula (1). (In formula (1), R3 represents a hydrogen atom, a halogen group, a nitro group, an amino group, a carbonyl group, an aryl group having 6-40 carbon atoms, or an aryl group having 6-40 carbon atoms or heterocyclic group which may be substituted by a hydroxy group; R4 represents a hydrogen atom, a halogen group, a nitro group, an amino group, or an alkyl group having 1-10 carbon atoms, aryl group having 6-40 carbon atoms or heterocyclic group which may be substituted by a hydroxy group; R3 and R4 may combine to form a ring together with carbon atoms to which R3 and R4 are bonded; and n represents an integer of 0-2.) In formula (1), R3 is a benzene ring, a naphthalene ring, an anthracene ring or a pyrene ring, and R4 is a hydrogen atom.