A new underlayer composition that exhibits high etch resistance and
improved optical properties is disclosed. The underlayer composition
comprises a vinyl or acrylate polymer, such as a methacrylate polymer,
the polymer comprising at least one substituted or unsubstituted
naphthalene or naphthol moiety, including mixtures thereof. Examples of
the polymer of this invention include: where each R.sub.1 is
independently selected from an organic moiety or a halogen; each A is
independently a single bond or an organic moiety; R.sub.2 is hydrogen or
a methyl group; and each X, Y and Z is an integer of 0 to 7, and Y+Z is 7
or less. The organic moiety mentioned above may be a substituted or
unsubstituted hydrocarbon selected from the group consisting of a linear
or branched alkyl, halogenated linear or branched alkyl, aryl,
halogenated aryl, cyclic alkyl, and halogenated cyclic alkyl, and any
combination thereof. The compositions are suitable for use as a
planarizing underlayer in a multilayer lithographic process, including a
trilayer lithographic process.