a first die having a signal region and a dummy region that surrounds the signal region, wherein the signal region is disposed in a center of the first die, and wherein the first die includes a plurality of first vias disposed in the signal region;

a second die stacked on the first die, wherein the second die includes a plurality of second vias disposed in the signal region, and wherein the second vias are positioned corresponding to the first vias;

a plurality of first die pads disposed in the signal region and on a top surface of the first die, wherein the first die pads are coupled to the first vias, and wherein each of the first die pads has a circular planar shape;

a plurality of first connection terminals disposed between the first die and the second die on the first die pads, wherein the first connection terminal couple the second vias to the first vias;

a plurality of second die pads disposed in the dummy region on the top surface of the first die and including a plurality of corner die pads and a plurality of lateral die pads, wherein each of the second die pads has a rectangular planar shape; and

a plurality of second connection terminals disposed between the first die and the second die on the second die pads, wherein the second connection terminals are electrically insulated from both the first vias and the second vias,

wherein the corner die pads are radially arranged adjacent to a corner of the second die, and wherein each of the corner die pads has a major axis that is oriented towards a center of the second die.