Evaluation of additives and current mode on copper via filling

Copper via filling by electroplating method became a common technology for interlayer metallization in 3D SiP and then it has been extensively studied. The void free copper via can be obtained with varying the additives on the electrolytes and the current density and mode. The effects of current mode and additives on the copper via filling were investigated. The acid copper electrolytes containing additives were examined to fill 10~20um via hole without void. The different sized vias were successfully filled with copper varying current density and mode after fixing additive conditions. The effect of pulse duty cycle on via filling was also investigated.