COPOLYMER FOR PHOTORESIST COMPRISING THE CROSSLINKING AGENT, WHICH CONTAINS TWO (METH)ACRYLATE UNITS AND CHEMICALLY AMPLIFIED RESIST COMPOSITION CONTAINING IT

摘要

A copolymer, a chemically amplified photoresist composition containing the copolymer, and a method for forming a chemically amplified photoresist pattern by using the composition are provided to improve the contrast between exposed region and unexposed region and resolution and to reduce line edge roughness. A copolymer is represented by the formula 9 and contains a crosslinking agent represented by the formula 1 as a repeating unit, wherein R1, R4, R5 and R6 are independently a substituted or unsubstituted C1-C20 alkyl or cyclic alkyl group containing an ether group, an ester group, a carbonyl group, an acetal group, an epoxy group, a nitrile group, a halogen atom or an aldehyde group; R2 and R3 are independently H or a methyl group; 0.1<l/(l+m+m+o)<0.7; 0.1<m/(l+m+m+o)<0.5; 0.1<=n/(l+m+m+o)<0.5; and 0.01<=o/(l+m+m+o)<0.2.