MECHANISMS FOR FORMING COPPER PILLAR BUMPS USING PATTERNED ANODES

摘要

This disclosure relates to a bump structure on a substrate including a copper layer, wherein the copper layer fills an opening created in a dielectric layer and a polymer layer. The bump structure further includes an under-bump-metallurgy (UBM) layer lines the opening and the copper layer is deposited over the UBM layer. The bump structure further includes a surface of the copper layer facing away from the substrate is curved. This disclosure also relates to two bump structures with different heights on a substrate where a thickness of the first bump structure is different than a thickness of the second bump structure. This disclosure also relates to a semiconductor device including a bump structure.