Patent ID: RE40983

Claim:
A method for plating a second metal directly to a first metal, said method comprising the steps of : providing a semiconductor substrate including at least one metal feature and at least one insulating layer covering said metal feature and said substrate; forming at least one recess in said at least one insulating layer thereby exposing at least a portion of said metal feature; forming at least one conductive barrier layer over said insulating layer and said exposed portion of said metal feature; forming a plating seed layer of a first metal over said at least one barrier layer; depositing a photoresist layer over said plating seed layer and in said at least one recess ; removing portions of said photoresist layer and portions of said plating seed layer outside of said at least one recess; removing photoresist remaining in said at least one recess; and electroplating a second metal to said plating seed layer in said recess without utilizing a lithographic mask.