The chemical amplification die negative die photoresist constituent for the thick film, the photoresist backing material and the bump formation manner which uses this

摘要

To provide a chemically amplified negative photoresist composition for thick films having high sensitivity and good plating resistance and suitable for the formation of thick films favorable for use as materials for forming bumps and re-wiring and a metal post used in a CSP manufacturing technique and to provide a photoresist base material and a method for forming bumps using the same. SOLUTION: In the chemically amplified negative photoresist composition for thin films having 20-150 μ m thickness including (A) an alkali-soluble resin, (B) a compound which generates an acid upon irradiation with a radiant ray and (C) a compound which takes part in a crosslinking reaction in the presence of an acid and the component (A) comprises a mixture of (a1) a novolak resin having a weight average molecular weight of 5,000-10,000 and (a2) a copolymer containing at least a hydroxystyrene constitutional unit and having a weight average molecular weight of =5,000.