Copper Pulse-Reverse Current Electrodeposition to Fill Blind Vias for 3-D TSV Integration

The through-silicon-via (TSV) interconnection in 3-D integration is one solution being explored to solve current 2-D interconnect problems in the semiconductor industry. In this paper, TSV fillings by pulse-reverse current electrodeposition of Cu with various parameters were carried out to improve the via filling performance. Especially, the influence of current density and electrodepositing time on the TSV filling property was studied. The high aspect ratio reaching 6:1 in via filling was achieved by applying the pulse-reverse current form, which was mainly caused by effective adsorption and redistribution of additives inside via.