| abstract |
There is provided a novel resist underlayer film forming composition comprising a polymer having a repeating structural unit of formula (1a) and/or (1b): n n[wherein two R 1 s are each independently a C 1-10 alkyl group, a C 2-6 alkenyl group, an aromatic hydrocarbon group, a halogen atom, a nitro group, or an amino group, two R 2 s are each independently a hydrogen atom, a C 1-10 alkyl group, a C 2-6 alkenyl group, an acetal group, an acyl group, or a glycidyl group, R 3 is an aromatic hydrocarbon group optionally having a substituent or a heterocyclic group, R 4 is a hydrogen atom, a phenyl group, or a naphthyl group, two ks are each independently 0 or 1, m is an integer of 3 to 500, p is an integer of 3 to 500, X is a benzene ring, and two —C(CH 3 ) 2 — groups bonded to the benzene ring are in a meta position or a para position], and a solvent. |