STRUCTURE AND PROCESS FOR METALLIZATION IN HIGH ASPECT RATIO FEATURES

A high aspect ratio metallization structure is provided in which a noble metal-containing material is present at least within a lower portion of a contact opening located in a dielectric material and is in direct contact with a metal semiconductor alloy located on an upper surface of a material stack of at least one semiconductor device. In one embodiment, the noble metal-containing material is plug located within the lower region of the contact opening and an upper region of the contact opening includes a conductive metal-containing material. The conductive metal-containing material is separated from plug of noble metal-containing material by a bottom walled portion of a U-shaped diffusion barrier. In another embodiment, the noble metal-containing material is present throughout the entire contact opening.