Effectiveness of Stepwise Current Wave Form in ULSI Copper Electroplating

Abstract

Copper electroplating is greatly interested in ULSI technology because of copper damascene process. We have already reported that void-free copper fill can be achieved by the selection of proper additives. However, inclusion of additives in copper deposit may cause deposit deterioration. A possibility of copper filling by the wave form control was examined using additive free bath. The void-free filling can be achieved by current density in stepwise current wave form by changing from lower to higher current.