Radiation sensitive resin composition and material for forming bumps containing the same

Abstract

A radiation sensitive resin composition comprising: (A) an alkali-soluble copolymer comprising: (a) 10 to 50% by weight of a first unit consisting of a radical polymerizable compound having a carboxylic group, (b) 20 to 60% by weight of a second unit consisting of a radical polymerizable compound having a cycloalkyl group, the unit containing no carboxyl group, and (c) 5 to 40% by weight of a third unit consisting of a radical polymerizable compound other than the radical polymerizable compounds in (a) and (b) above; (B) a polymerizable compound having at least one ethylenically unsaturated double bond; and (C) a radiation sensitive radical initiator. Also is disclosed a material for forming bumps containing the radiation sensitive resin composition. The radiation sensitive resin composition has sufficient developability with an alkali developer and sufficient resolution when the composition is in the form of a 20 .mu.m or more thick film. The composition and material of the present invention have excellent resistance to plating liquids and good wettability to plating liquids, and improved adhesion to substrates upon development. Therefore, the composition and material of the present invention can form bumps having sufficient characteristics by plating and give rise to a cured product which has excellent peelability from the substrate on which it is formed.

Dependencies are inferred from the claim text.