US Patent 9984919 Inverted damascene interconnect structures

Interconnect structures and methods of fabricating an interconnect structure. A first section of a mandrel is covered with a feature of an etch mask. A top surface of a second section of the mandrel is exposed by the feature of the etch mask and is recessed with an etching process. A conductive via is formed that reproduces a shape of the first section of the mandrel, and a conductive line is formed that reproduces a shape of the second section of the mandrel. The mandrel is removed to release the conductive via and the conductive line.