UBM FORMATION FOR INTEGRATED CIRCUITS

摘要

PURPOSE: A method for forming an under-bump-metallurgy on an integrated circuit is provided to increase the lateral size of the under-bump-metallurgy by horizontally growing the under-bump-metallurgy in an initial plating process. CONSTITUTION: A metal pad (30) is formed on a metal layer (24). A passivation layer (32) is formed on the metal pad. A polymer layer (36) is formed on the passivation layer. An opening part is formed on the polymer layer to expose a part of the metal pad. An under-bump-metallurgy (46) is formed by a chemical plating process. The under-bump-metallurgy includes a part which is extended to the opening part to be connected to the metal pad.