Patent ID: 8232647

Claim:
A semiconductor structure comprising: at least one semiconductor device located on a surface of a semiconductor substrate, said at least one semiconductor device including at least a material stack comprising, from bottom to top, a gate dielectric, a gate conductor, and a metal semiconductor alloy; a dielectric material located on said surface of said semiconductor substrate, said dielectric material including a contact opening that extends from an upper surface of the dielectric material to the metal semiconductor alloy of said material stack, said contact opening having an aspect ratio of greater than 3:1; a metal present within a lower region of said contact opening, said metal is in direct contact with said metal semiconductor alloy of said material stack and wherein said metal is selected from the group consisting of at least one of Ru, Rh, In, Pd, Co and Pt; and a conductive metal-containing material located within an upper portion of said contact opening, said conductive metal-containing material is separated from said metal by a bottom wall portion of at least a U-shaped diffusion barrier, and wherein said conductive metal-containing material and said U-shaped diffusion barrier each having an upper surface that is coplanar with an upper surface of the dielectric material.