A plug connector has an insulative housing, a plurality of first terminals, a plurality of second terminals and a positioning bracket. The optical device includes a bracket secured with a stator of the spindle motor. The plugging tool includes an outer housing containing an eutectic metal alloy. Upon proper framing, a converter converts the pentad back to a DS3 frame at the output for processing with other interfaces. A plurality of second non-dielectric pillars and first vias are formed in a first low-k dielectric layer underlying the topmost low-k layer in the scribe line region, wherein the second non-dielectric pillars electrically connect the first non-dielectric pillars by the first vias, respectively.