A method of manufacture of an integrated circuit system includes: providing a substrate with a face surface having a via therein and a back surface having a trench therein; filling the via with a conductive pillar; forming a recessed contact pad in the trench; filling the recessed contact pad partially with solder; and forming an under-bump metal having a base surface in electrical contact with the conductive pillar, and having sides that extend away from the face surface of the substrate and further extend beyond the base surface.