Patent ID: 8241701

Claim:
A method of preparing a substrate surface of a substrate to deposit a metallic barrier layer to line a copper interconnect structure of the substrate and to deposit a thin copper seed layer on a surface of the metallic barrier layer in an integrated system to improve electromigration performance of the copper interconnect, comprising: cleaning an exposed surface of a underlying metal to remove surface metal oxide in a first module of the integrated system, wherein the underlying metal is part of a underlying interconnect electrically connected to the copper interconnect structure; reducing a surface of the metallic barrier layer to convert metallic barrier oxide on the surface of the metallic barrier layer to make the surface of the metallic barrier layer to be metal-rich in the integrated system, wherein reducing the surface of the metallic barrier layer is performed after the exposed surface of the underlying metal is cleaned; depositing the metallic barrier layer to line the copper interconnect structure in a second module of the integrated system; depositing the thin copper seed layer in a third module of the integrated system; and depositing a gap-fill copper layer over the thin copper seed layer in a fourth module of the integrated system, wherein transfers along the first, second, third, and fourth modules occurring in an inert gas filled environment, and wherein the transfers occurring in the inert gas filled environment reduce formation of metal oxides over the copper interconnect structure, the metallic barrier layer, and the thin copper seed layer before the gap-fill copper layer is deposited, and wherein the fourth module is a copper plating process system used for depositing the gap-fill copper layer and the copper plating process system is filled with an inert gas to ensure low levels of oxygen in the processing environment, and wherein the copper plating process system used to process the substrate uses dry-in/dry-out processing of the substrate to allow the substrate to go in and to come out of the copper plating process system in a dry state.