Chemically amplified negative resist composition and patterning process

摘要

A chemically amplified negative resist composition is provided comprising (A) an alkali-soluble base polymer, (B) an acid generator, and (C) a nitrogen-containing compound, the base polymer (A) turning alkali insoluble under the catalysis of acid. A polymer having a fluorinated carboxylic acid onium salt on a side chain is included as the base polymer. Processing the negative resist composition by a lithography process may form a resist pattern with advantages including uniform low diffusion of acid, improved LER, and reduced substrate poisoning.

主权项

1. A chemically amplified negative resist composition comprising (A) a base polymer which is soluble in an aqueous alkaline developer, (B) an acid generator capable of generating an acid catalyst, and (C) a nitrogen-containing compound as a basic component, said base polymer as component (A) turning alkali insoluble under the action of the acid catalyst in the presence or absence of a crosslinker, wherein
a polymer comprising recurring units of a fluorinated carboxylic acid onium salt having the general formula (1) and having a weight average molecular weight of 1,000 to 50,000 is included as at least a portion of said base polymer,wherein R1 is a structure derived from a basis skeleton capable of providing the polymerization activity of a polymerizable monomer, represented by any one of the formulae:wherein the valence bond extending from the oxygen atom in the structure designates a bond to W1,
R2 is fluorine or a fluoroalkyl group, W1 is a divalent organic group, and Q+ is a sulfonium cation of the general formula (a) or (b) or a iodonium cation of the general formula (c):wherein R3, R4 and R5 are each independently a substituted or unsubstituted, straight or branched C1-C10 alkyl, alkenyl or oxoalkyl group or a substituted or unsubstituted C6-C18 aryl, aralkyl or aryloxoalkyl group, or at least two of R3, R4 and R5 may bond together to form a ring with the sulfur atom,wherein R6 is a substituted or unsubstituted, straight, branched or cyclic C1-C20 alkyl or alkenyl group or a substituted or unsubstituted C6-C14 aryl group, m is an integer of 1 to 5, n is 0 or 1, R6 may have a carbonyl group, hydroxyl group, ester structure, lactone structure, amino group, amide group or ether-bonding oxygen atom substituted thereon,wherein R6 is a substituted or unsubstituted, straight, branched or cyclic C1-C20 alkyl or alkenyl group or a substituted or unsubstituted C6-C14 aryl group, m is an integer of 1 to 5, n is 0 or 1, R6 may have a carbonyl group, hydroxyl group, ester structure, lactone structure, amino group, amide group or ether-bonding oxygen atom substituted thereon.