Conductive structures and method of manufacture thereof are disclosed. A barrier layer can line the first recess of a substrate. A first seed layer can be formed on the barrier layer and line a bottom of the first recess and partially line sidewalls of the recess. A first conductive material can partially fill the first recess to form a second recess. The top surface of the first conductive material can coincide with a vertical extent of the first seed layer and have a depression formed therein. A second seed layer can be formed on the barrier layer and line the second recess. A second conductive material can fill the second recess.