Copper interconnect structure with amorphous tantalum iridium diffusion barrier

摘要

A method of forming a diffusion barrier for use in semiconductor device manufacturing includes depositing, by a physical vapor deposition (PVD) process, an iridium doped, tantalum based barrier layer over a patterned interlevel dielectric (ILD) layer, wherein the barrier layer is deposited with an iridium concentration of at least 60 atomic % such that the barrier layer has a resulting amorphous structure.