Integrated circuit structure having through-silicon via and method of forming same

A method of forming an integrated circuit structure, the method comprising:

• removing a portion of a wafer to expose a through-silicon-via (TSV) on a back side of the wafer;
• forming a first passivation layer over the exposed TSV and over the back side of the wafer;
• forming a first dielectric layer over the first passivation layer over the back side of the wafer, the first dielectric layer including a first opening that exposes a first portion of the first passivation layer over the TSV and a second portion of the first passivation layer in an area adjacent to the TSV;
• forming a first seed layer over the back side of the wafer and within the first opening over the exposed first and second portions of the first passivation layer;
• forming a first metal over the back side of the wafer and within the first opening over the first seed layer;
• planarizing the first metal, the first passivation layer, and the TSV to a top surface of the first dielectric layer and to expose a second metal of the TSV;
• and
• forming a conductive pad over the first metal and the TSV such that the conductive pad provides electrical connection between the second metal of the TSV and the first metal, the conductive pad including a second seed layer and a third metal,
• wherein the second seed layer is distinct from the first seed layer.

An integrated circuit structure having a front side and back side opposing the front side, the integrated circuit structure comprising:

• a through-silicon-via (TSV) at least partially within a dielectric layer extending away from the front side;
• a first metal adjacent to the TSV and within a first seed layer within the dielectric layer;
• a second metal adjacent to the TSV on an opposing side of the TSV relative to the first metal, the second metal being within a second seed layer within the dielectric layer;
• and
• a conductive pad over the first metal, the second metal, and the TSV, and extending away from the front side, wherein the conductive pad provides electrical connection between the TSV, the second metal, and the first metal, and wherein the conductive pad includes a third metal within a third seed layer,
• wherein the third seed layer separates the third metal from the first metal the second metal, and the TSV.