Apparatus, and methods of manufacture thereof, in which metal is deposited into openings, thus forming a plurality of metal pads, a plurality of through-silicon-vias (TSVs), a plurality of metal lines, a plurality of first dummy structures, and a plurality of second dummy structures. Ones of the plurality of first dummy structures each have a first width that is at least about three times greater than a second width of each of the plurality of metal lines, and ones of the plurality of second dummy structures each have a third width that is at least about five times greater than the second width of each of the plurality of metal lines.