Abstract: A method is provided for preventing the formation of oxides in the process of creating a connection aperture through an insulating layer overlying a copper conductor having a connection surface region. The method deposits at least two insulation layers over the copper connection region including a nitride dielectric material adjacent the connection region, and a second insulating material adjacent the nitride layer. An area of the second insulator is selectively removed to partially form a connection aperture extending to the nitride layer. Next, an area of the nitride layer, and any layer overlying the nitride layer, is selectively removed to form an aperture in registration with the aperture formed in the second layer. The completed connection aperture extends through the entire insulating layer to the connection region. The nitride layer protects the copper from processes that cause oxidation as the layers overlying the nitride layer are removed.

Abstract: A method has been provided for improving the adhesion of Cu to a diffusion barrier material, such as TiN, in an integrated circuit substrate. The diffusion barrier is exposed to either a reactive oxygen species, or a plasma containing oxygen. A thin layer of the diffusion barrier is oxidized, typically less than 50 .ANG., in response to exposure to the oxygen environment. CVD copper is then deposited over the oxidized diffusion barrier surface. The oxide layer improves bonding between the copper and diffusion barrier surfaces. The oxide layer permits the control of tolerances in the diffusion barrier preparation processes, and copper precursor, to be relaxed. An integrated circuit comprising an oxide layer between the diffusion barrier and the copper layer is also provided.