Material and process for advanced Cu/ULK integration

Abstract

Copper metallization at 32nm and beyond poses multiple technical challenges to the semiconductor industry for its continued evolution. It becomes necessary to consider alternative liner materials, deposition processes, and integration schemes together to successfully meet the technology extendibility, circuit performance and reliability requirements. This paper describes a new enhanced via integration scheme which includes a novel patterning technique coupled with a conformally deposited CVD Ru adhesion layer between the TaN diffusion barrier and the Cu interconnect. The new scheme shows potential as a replacement to the conventional "via punch-through" integration scheme with physical vapor-deposited (PVD) Ta adhesion layer. © 2009 Materials Research Society.