A novel chemically, thermally and electrically robust Cu interconnect structure with an organic non-porous ultralow-k dielectric fluorocarbon (k=2.2)

摘要

A novel chemically, thermally and electrically robust Cu damascene interconnects with an organic non-porous ultralow-k (ULK) dielectric fluorocarbon (k=2.2), deposited by an advanced microwave excited plasma enhanced CVD, is demonstrated. A practical nitrogen plasma treatment (NPT) was employed to minimize chemically damage introduction to fluorocarbon in post-etching cleaning and CMP processes. Also, a new structure with a delamination-protective-liner (DPL), instead of barrier-metal, between Cu and fluorocarbon is introduced to avoid thermally induced electrical degradation and to reduce the interconnect delay significantly (by >30% in 32 nm-node). Non-porous ULK fluorocarbon with NPT and DPL technologies is a promising candidate for high performance Cu interconnects.