Structure and method for contact pads having an overcoat-protected bondable metal plug over copper-metallized integrated circuits

摘要

A metal structure for a contact pad of an integrated circuit (IC), which has copper interconnecting metallization ( 311 ). A portion ( 301 ) of this metallization is exposed to provide a contact pad to the IC. A conductive barrier layer ( 330 ) is positioned on the exposed portion of the copper metallization. A plug ( 350 ) of bondable metal, preferably aluminum between about 0.4 and 1.4 mum thick, is positioned on the barrier layer. A protective overcoat layer ( 320 ) surrounds the plug and has a thickness ( 320 b) so that the exposed surface ( 322 ) of the plug lies at or below the exposed surface ( 320 a) of the overcoat layer. Optionally, a portion ( 321 ) of the overcoat layer between about 0.1 and 0.3 mum wide may overlap the perimeter of the plug.