Processes and systems for engineering a copper surface for selective metal deposition

Abstract

The embodiments fill the need to enhance electro-migration performance, provide lower metal resistivity, and improve metal-to-metal interfacial adhesion for copper interconnects by providing improved processes and systems that produce an improved metal-to-metal interface, more specifically copper-to-cobalt-alloy interface. An exemplary method of preparing a substrate surface of a substrate to selectively deposit a thin layer of a cobalt-alloy material on a copper surface of a copper interconnect of the substrate in an integrated system to improve electromigration performance of the copper interconnect is provided. The method includes removing contaminants and metal oxides from the substrate surface in the integrated system, and reconditioning the substrate surface using a reducing environment after removing contaminants and metal oxides in the integrated system. The method also includes selectively depositing the thin layer of cobalt-alloy material on the copper surface of the copper interconnect in the integrated system after reconditioning the substrate surface. An exemplary system to practice the exemplary method described above is also provided.