Effects of Leveler Concentration in High Aspect Ratio Via Filling in 3D SiP

Abstract

3D packaging field is actively being studied in order to obtain better characteristics, such as shorter interconnection, reduction in signal delay, etc. Electroplating copper via filling is the most important technology in 3D stacking interconnection of SiP. Copper is inexpensive electrode material that has excellent electrical properties and easily obtained. In this study, the effects of leveler concentration in high aspect ratio via filling was investigated without the addition of other additives such as inhibitor and accelerator. Tetronic 701 was used as leveler. The effects of leveler on copper deposition was investigated using galvanostatic, polarization and cyclic voltammetric techniques. High overpotential of copper deposition in tetronic 701 added solution was confirmed. Finally, the optimum conditions of copper via filling in high aspect ratio via (diameter 10 μm, depth 150 μm, AR 15) was obtained.