Semiconductor chip and method for fabricating the same

A semiconductor chip comprising:

• a silicon substrate;
• at least one semiconductor device in or over said silicon substrate;
• a first dielectric layer over said silicon substrate;
• a metallization structure over said first dielectric layer, wherein said metallization structure is connected to said at least one semiconductor device, and wherein said metallization structure comprises a first metal layer and a second metal layer over said first metal layer;
• a second dielectric layer between said first and second metal layers;
• a passivation layer over said metallization structure and over said first and second dielectric layers, a first opening in said passivation layer exposing a pad of said metallization structure;
• a polymer bump on said passivation layer and on said pad exposed by said first opening, a second opening in said polymer bump exposing said pad, wherein said polymer bump has a thickness of between 5 and 25 micrometers and a width between 10 and 40 micrometers;
• an adhesion/barrier layer on said pad exposed by said second opening and on a top surface of said polymer bump;
• a seed layer on said adhesion/barrier layer;
• and
• a third metal layer on said seed layer, wherein the material of said third metal layer is the same as that of said seed layer.