| 摘要 |
PROBLEM TO BE SOLVED: To enhance transparency, sensitivity, dry etching resistance, adhesion and resolution by using a new acrylic copolymer having a thiophene residue and an ester residue introduced into a side chain. SOLUTION: The ArF positive type photo-image forming composition contains a copolymer obtained by copolymerizing a 2-thienylalkyl (meth)acrylate and a (meth)acrylic ester and a photo-acid generating agent as essential components. The photo-acid generating agent is 4-phenylthiophenyldiphenylsulfonium hexafluoroantimonate. When an acid propagator is further contained, a proton formed from the photo-acid generating agent acts catalytically to the acid propagator and a large quantity of a new strong acid is released in geometric progression. By the catalytic actions of all the acids, ester groups such as tertiary alkyl ester groups in the acrylic copolymer cause elimination and become (meth)acrylic acid groups by accelerative degradation, accordingly sensitivity is enhanced. |
