A study on the formation of Through-Silicon-Via(TSV) by electrochemical deposition.

Abstract

Currently, the through silicon via (TSV) technology which was three-dimensionally interconnects the electric circuits was studied for the power efficiency and effective operation of the memory or logic devices. The copper was usually filled in the TSV due to its high electrical conductivity, chip price and convenience of the electrodeposition process. The nanotwinned copper (NT-Cu) which has ultra-high strength and low electrical resistivity was also investigated to replace the conventional copper. In this study, various experiments for understanding basic mechanism of TSV filling was carried out. It was investigated that several pre-treatments to form the well prepared condition of the TSV sample before the electrodeposition process. It was also studied that effect of additives and concentration of ion in the electrolyte. Finally, TSV was filled by pulsed current electrodeposition to forms the nanotwinned copper in the TSV. The microstructure of filled Cu in the TSV was identified by transmission electron microscope (TEM). Tensile strength, electrical resistivity and thermal extrusion property were also investigated.