Methods and apparatus for cleaning metal contacts

A method for cleaning a contaminated metal surface on a substrate, comprising:

• exposing a substrate comprising a dielectric surface and a metal surface comprising metal nitride residues and metal carbide residues to a process gas comprising an oxidizing agent to form a substrate comprising a dielectric surface and a metal surface comprising metal oxides residues, wherein the process gas comprising an oxidizing agent comprises a mixture of oxygen and argon, or a mixture of oxygen and helium;
• and
• exposing the substrate comprising a dielectric surface and a metal surface comprising metal oxides residues to a process gas comprising a reducing agent to form a substrate comprising a dielectric surface and a substantially pure metal surface, wherein the reducing agent is a mixture of hydrogen and argon, hydrogen and nitrogen or hydrogen and helium.

A non-transitory computer readable medium having instructions stored thereon that, when executed, cause a reaction chamber to perform a method of cleaning a contaminated metal surface on a substrate, the method comprising:

• exposing a substrate comprising a dielectric surface and a metal surface comprising metal nitride residues and metal carbide residues to a process gas comprising an oxidizing agent to form a substrate comprising a dielectric surface and a metal surface comprising metal oxides residues;
• and
• exposing the substrate comprising a dielectric surface and a metal surface comprising metal oxides residues to a process gas comprising a reducing agent to form a substrate comprising a dielectric surface and a substantially pure metal surface.