Patterning process and resist composition

摘要

A negative pattern is formed by coating a resist composition comprising (A) a polymer having an acid labile group, adapted to change its polarity under the action of acid, (B) a photoacid generator, and (C) an organic solvent onto a substrate, baking, exposing the resist film to high-energy radiation, PEB, and developing in an organic solvent-based developer to selectively dissolve the unexposed region of resist film. The photoacid generator has the formula: R1—COOC(CF3)2—CH2SO3−R2R3R4S+ wherein R1 is a monovalent hydrocarbon group, R2, R3 and R4 are an alkyl, alkenyl, oxoalkyl, aryl, aralkyl or aryloxoalkyl group, or may bond together to form a ring with the sulfur atom.

主权项

1. A process for forming a negative pattern, comprising the steps of coating a resist composition comprising (A) a polymer having an acid labile group, adapted to change its polarity under the action of acid, (B) a photoacid generator, and (C) an organic solvent onto a substrate, baking the coating to form a resist film, exposing the resist film to high-energy radiation to define exposed and unexposed regions, baking, and developing the resist film in a developer selected from the group consisting of ketones and esters to selectively dissolve the unexposed region of resist film,
said photoacid generator (B) having the general formula (1):
R1—COOC(CF3)2—CH2SO3−R2R3R4S+  (1)wherein R1 is a straight, branched or cyclic, monovalent hydrocarbon group of 1 to 50 carbon atoms which may contain a heteroatom, R2, R3 and R4 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 R2, R3 and R4 may bond together to form a ring with the sulfur atom, and
said polymer (A) comprises recurring units having the general formula (2):wherein R5 is hydrogen or methyl, R6 is a straight, branched or cyclic, divalent aliphatic hydrocarbon group of 2 to 16 carbon atoms which may contain an ether or ester bond, R7 is tert-pentyl or neopentyl, m is 0 or 1, and n is 1 or 2.