Through silicon via structure

A through silicon via structure, comprising:

• a substrate;
• a first dielectric layer disposed on the substrate and having a plurality of first openings, wherein a bottom of the plurality of first openings is located lower than an original surface of the substrate;
• a via hole disposed through the first dielectric layer and the substrate, wherein the via hole not overlapping for all of the plurality of first openings;
• a second dielectric layer disposed within the plurality of first openings and on a sidewall of the via hole while filling the plurality of first openings completely;
• and
• a conductive material layer disposed within the via hole having the second dielectric layer on the sidewall of the via hole, thereby forming a through silicon via, wherein the second dielectric layer comprises a plurality of second openings corresponding to the plurality of first openings, and the conductive material layer is further disposed within the plurality of second openings to form a plurality of dummy through silicon vias.