ETCHANT FOR UNDER BUMP MULTI-METALLIZATION LAYER OF FLIP CHIP

摘要

PURPOSE: An etchant for under bump multi-metallization(UBM) layer of a flip chip is provided to form a bump and the UBM layer having a high reliability by etching the UBM layer using the etchant so as to complete the bump, and solidly package the flip chip accordingly using the bump and UBM layer that are formed by using the etchant. CONSTITUTION: The etchant for under bump multi-metallization(UBM) layer(350) of a flip chip comprises a first etchant for a copper film(356) comprising 0.96 to 4.8 wt.% of sulfuric acid, 0.32 to 1.6 wt.% of hydrogen peroxide and a balance of water; a second etchant for a chromium/copper mixed film(354) comprising 19.2 to 96 wt.% of hydrochloric acid, 0.32 to 1.6 wt.% of hydrogen peroxide and a balance of water; and a third etchant for a chromium film(352) comprising 6.4 to 32 wt.% of hydrochloric acid and a balance of water.