Patent ID: 8216940

Claim:
A method for manufacturing a semiconductor device, comprising: forming a first insulating film on a substrate; forming a first interconnect trench in said first insulating film; forming a first copper containing metal film in said first interconnect trench; forming a second insulating film on said first copper containing metal film and said first insulating film; forming a connection hole reaching an upper face of said first copper containing metal film, and a second interconnect trench located on said connection hole, in said second insulating film; forming a barrier metal film within said connection hole and contacting said upper face of said first copper containing metal film; removing a portion of said barrier metal film contacting said first copper containing metal film to expose a portion of said upper surface; forming a seed metal film including a copper element and different metal elements so as to come into contact with the exposed upper face of said first copper containing metal film, on inner portions of said connection hole and said second interconnect trench; forming a second copper containing metal film so as to come into contact with an upper face of said seed metal film, on inner portions of said connection hole and said second interconnect trench; and carrying out heat treatment of said first copper containing metal film and said seed metal film, thereby distributing the different metal elements into the first copper containing metal film.