Formation mechanism and suppression methods of copper dendrites in BEOL integration

Abstract

Dendrites can be suppressed by an alternative CMP clean process. 12-hour lag time between plating and furnace anneal can also suppress formation of dendrites. In manufacturing, 12 hours of lag time between plating and anneal is impacting cycle time. Above results indicates that optimizing Cu metallization including annealing, plating, and CMP is very important to suppress the formation of dendrites.