| abstract |
PROBLEM TO BE SOLVED: To provide a positive photoresist composition and a photoresist which are excellent in adhesion to a substrate, plating solution resistance, developability, and peelability from the substrate, and suitable for forming a thick film suitable as a material for forming a bump. Provided are a film and a bump forming method using the same. (A) An alkali-soluble novolak resin, A positive photoresist composition for a thick film having a thickness of 5 to 100 μm, comprising (B) an alkali-soluble acrylic resin and (C) a quinonediazide group-containing compound, wherein the component (B) comprises (b) 1) 30 to 90% by weight of a structural unit derived from a polymerizable compound having an ether bond, and (b2) a structural unit 50 derived from a polymerizable compound having a carboxyl group. ２2% by weight. This composition is applied on a substrate and dried to obtain a photoresist film. Further, the composition is applied on a substrate of an electronic component, patterned, and plated to form a bump. |