In one aspect of the invention, a method for fabricating an advanced metal conductor structure includes a conductive line pattern including a set of conductive line trenches in a dielectric layer. Each conductive line trench of the conductive line pattern has parallel vertical sidewalls and a horizontal bottom. A surface treatment of the dielectric layer is performed. The surface treatment produces an element enriched surface layer in which a concentration of a selected element in a surface portion of the parallel sidewalls and horizontal bottoms of the conductive line trenches is increased. A first metal layer is deposited on the element enriched surface layer. A first thermal anneal is performed which simultaneously reflows the first metal layer to fill a first portion of the conductive line trenches and causes a chemical change at interfaces of the first metal layer and the element enriched surface layer creating a liner which is an alloy of the first metal and selected element. A second metal layer is deposited. A second thermal anneal is performed which reflows the second metal layer to fill a remaining portion of the conductive line trenches. Another aspect of the invention is a device formed by the process.