Barrier Slurry Innovation for Advanced Node

As the development of technology node, ULK was used as isolation material in Cu damascene integration. ULK is a porous material with low mechanical strength and low adhesion. During CMP process, slurry additive and moisture will enter the hole of ULK material and result in the increasing of ULK K value, and also ULK film is easily damaged by mechanical force. To solve this problem, a capping layer is designed in Cu integration. In this paper, a novel barrier is developed to meet this integration need. Slurry chemistry/additives effect on RR selectivity and topo is evaluated in this paper.