A method for fabricating an advanced metal conductor structure is described. A pattern in a dielectric layer is provided. The pattern includes a set of features in the dielectric for a set of metal conductor structures. An adhesion promoting layer is created over the patterned dielectric. A ruthenium layer is deposited over the adhesion promoting layer. Using a physical vapor deposition process, a cobalt layer is deposited over the ruthenium layer. A thermal anneal is performed which reflows the cobalt layer to fill the set of features to form a set of metal conductor structures.