Patent ID: 7176571
Filing Date: 2007-02-13
Classification: H01L

Abstract:
1. A damascene structure that includes a composite barrier layer formed on a substrate, comprising: (a) a substrate comprised of a cooper layer; (b) a composite barrier layer comprised of an upper silicon nitride layer and a lower silicon carbide layer on said substrate; (c) a dielectric layer formed directly on the upper silicon nitride layer; (d) an opening with sidewalls in said dielectric layer that extends through said composite barrier layer and exposes a portion of said copper layer; (e) a conformal diffusion barrier layer on the sidewalls of said opening; and (f) a planarized conductive layer on said conformal diffusion barrier layer that fills said opening, said planarized conductive layer is coplanar with the top of said dielectric layer, wherein an interface between said copper layer and said composite barrier layer is free of CuSi