Design structure embodied in a machine readable medium for designing, manufacturing, or testing a design. The design structure comprises an insulating layer of a dielectric material, an opening having sidewalls extending from a top surface of the insulating layer toward a bottom surface of the insulating layer, and a conductive feature disposed in the opening. The design structure includes a top capping layer disposed on at least a top surface of the conductive feature and a conductive liner layer disposed between the insulating layer and the conductive feature along at least the sidewalls of the opening. The conductive liner layer of the design structure has sidewall portions that project above the top surface of the insulating layer adjacent to the sidewalls of the opening.