Structure and method for contact pads having a recessed bondable metal plug over of copper-metallized integrated circuits

A wafer-level method of fabricating a metal structure for a contact pad of an integrated circuit having copper interconnecting metallization protected by an overcoat layer including silicon nitride, comprising the steps of:

• opening a window in said overcoat layer to expose said copper metallization, said window having walls reaching through the thickness of said overcoat layer;
• depositing a barrier metal layer over said wafer to cover said exposed copper metallization, window walls, and overcoat surface;
• depositing a bondable metal layer over said barrier layer in a thickness sufficient to fill said overcoat window;
• chemically-mechanically polishing said wafer so that said layers of bondable metal and barrier metal are removed over said overcoat outside said window;
• and
• chemically-mechanically polishing said wafer to remove the bondable metal and barrier metal to form a structural step of pre-determined height between the overcoat surface and the polished surface of the bondable metal.