International Business Machines Corporation
Bilayer barrier for interconnect and memory structures formed in the BEOL

Abstract:

An interconnect or memory structure is provided that includes a first electrically conductive structure having a concave upper surface embedded in a first interconnect dielectric material layer. A first metal-containing cap contacts the concave upper surface of the first electrically conductive structure. The first metal-containing cap has a topmost surface that is coplanar with a topmost surface of the first interconnect dielectric material layer. A second metal-containing cap having a planar bottommost surface contacts the topmost surface of the first metal-containing cap. A metal-containing structure having a planar bottommost surface contacts a planar topmost surface of the second metal-containing cap. A second electrically conductive structure contacts a planar topmost surface of the metal-containing structure, and a second interconnect dielectric material layer is present on the first interconnect dielectric material layer and is located laterally adjacent to second metal-containing cap, the metal-containing structure, and the second electrically conductive structure.