摘要 |
A copper (Cu) wiring forming method includes forming a barrier film on the entire surface of a wafer which has a trench, forming a ruthenium (Ru) film on the barrier film, and filling the trench by forming a pure copper film on the ruthenium film by a physical vapor deposition (PVD). The method further includes forming a copper alloy film on the pure copper film by the PVD, forming a copper wiring by polishing the entire surface by a chemical mechanical polishing, forming a cap layer made of a dielectric material on the copper wiring, and segregating an alloy component included in the copper alloy film in a region including a portion corresponding an interface between the copper wiring and the cap layer. |