POST-PASSIVATION INTERCONNECT STRUCTURE AND METHODS FOR FORMING THE SAME

摘要

A method according to an embodiment includes forming a polymer layer over a passivation layer, wherein the passivation layer further comprises a portion over a metal pad. The polymer layer is patterned to form an opening in the polymer layer, wherein exposed surfaces of the polymer layer have a first roughness. A surface treatment is performed to increase a roughness of the polymer layer to a second roughness greater than the first roughness. A metallic feature is formed over the exposed surface of the polymer layer.