Patent ID: 7498256

Claim:
A contact via structure comprising: an opening through a dielectric to a silicide region; a titanium (Ti) layer in direct contact with the silicide region lining a bottom and sidewalls of the opening; a titanium nitride (TiN) layer lining the titanium (Ti) layer within the opening, wherein the titanium nitride (TiN) layer is in direct contact with a bottom and sidewalls of the titanium (Ti) layer; a tantalum nitride (TaN) layer lining the titanium nitride (TiN) layer, wherein the tantalum nitride (TaN) layer is in direct contact with a bottom and sidewalls of the titanium nitride (TiN) layer; a tantalum (Ta) layer lining the tantalum nitride (TiN) layer, wherein the tantalum (Ta) layer is in direct contact with a bottom and sidewalls of the tantalum nitride (TiN) layer; a seed layer over the tantalum Ta layer, wherein the seed layer is in direct contact with a bottom and sidewalls of the tantalum (Ta) layer; and copper (Cu) filling a remaining portion of the opening.