Patent ID: 8470511

Claim:
A chemically amplified negative resist composition for EB or EUV lithography, comprising (A) an alkali-soluble polymer, (B) an acid generator capable of generating an acid catalyst, and (C) a nitrogen-containing compound as a basic component, said polymer as component (A) turning alkali insoluble under the action of the acid catalyst in the presence or absence of a crosslinker, wherein a basic polymer PB comprising recurring units of the general formulae (1) and (2) and having a weight average molecular weight of 1,000 to 50,000 serves as both components (A) and (C), wherein A is a single bond or a C 1 -C 10 alkylene group which may be separated by an ethereal oxygen atom, R 1 is each independently hydrogen or methyl, R 2 is each independently a C 1 -C 6 alkyl group, B 1 , B 2 , and B 3 are each independently a single bond, or a linkage selected from the group consisting of a straight or branched C 1 -C 10 alkylene group which may contain an ethereal oxygen atom, a divalent C 5 -C 10 alicyclic group which may be separated by an ethereal oxygen atom, a divalent C 6 -C 14 aromatic group which may be separated by an ethereal oxygen atom, and combinations comprising at least one of the foregoing, Z 1 and Z 2 are each independently a single bond, —CO—O— or —O—CO—, with the proviso that Z 1 and Z 2 do not form a —O—O— structure when B 1 , B 2 , and B 3 contain an ethereal oxygen atom, and B 3 is not a single bond when Z 2 is —CO—O— or —O—CO—, R 3 and R 4 are each independently hydrogen or a monovalent C 1 -C 10 hydrocarbon group which may contain a heteroatom, with the proviso that R 3 and R 4 are not hydrogen at the same time, R 3 and R 4 may bond together to form a ring with the nitrogen atom to which they are attached, and R 3 and R 4 are a divalent C 2 -C 12 hydrocarbon group which may contain a heteroatom when they form a ring, B 3 may bond with R 3 or R 4 to form a ring with the nitrogen atom to which they are attached, and in this case, the nitrogen-containing ring is a 5 to 7-membered ring which excludes a ring of the structure that a lone pair of the nitrogen atom renders the nitrogen-containing ring aromatic, and the nitrogen-containing ring is not an aromatic ring, a is an integer of 0 to 4, b is a positive integer of 1 to 5, p and q are each independently 0 or 1, t is an integer of 0 to 2, with the proviso that when q=0, the atom in B 1 that bonds with a main chain carbon is an ethereal oxygen atom or a carbon atom forming an aromatic ring, and when q=0 and Z 1 and Z 2 are single bonds, one or more of B 1 , B 2 , and B 3 should contain at least two consecutive carbon atoms originating from an alkylene group, or an aromatic group, wherein the recurring units of formula (1) are incorporated in a content of at least 64 mol % and the recurring units of formula (2) are incorporated in a content of 0.005 to 10 mol % based on the total recurring units in overall polymers in the resist composition.