Highly thermal-stable, plasma-polymerized BCB polymer film (k=2.6) for Cu dual-damascene interconnects

Abstract

Highly thermal-stable, plasma-polymerized divinyl siloxane bis-benzocyclobutene (p-BCB)-polymer film is developed for Cu dual-damascene interconnects. The thermal stability of p-BCB is improved over 400/spl deg/C by higher deposition temperature, having high resistance to Cu diffusion at 400/spl deg/C-annealing. Lowering the RF plasma-power and the deposition pressure, the p-BCB film has smaller dielectric constant than the conventional spin-coating BCB (k=2.7). The p-BCB (k=2.6)/Cu interconnects reveal 46% delay reduction of CMOS ring oscillator to the conventional SiO/sub 2//Al ones. The p-BCB is proved as a strong candidate for Cu/low-k interconnects.