A 65nm-node, Cu interconnect technology using porous SiOCH film (k=2.5) covered with ultra-thin, low-k pore seal (k=2.7)

A highly reliable, 65 nm-node Cu interconnect technology has been developed with 180 nm/200 nm-pitched lines connected through /spl phi/100 nm-vias. A porous SiOCH film (k=2.5) with sub-nanometer pores is introduced for the inter-metal dielectrics (IMD) on a non-porous, rigid SiOCH film (k=2.9) for the via-infra-line dielectrics (via-ILD). A key breakthrough is a special pore-seal technique, in which the trench-etched surface of the porous SiOCH is covered with an ultra-thin, low-k organic silica film (k=2.7), thus improving the line-to-line TDDB (time dependent dielectric breakdown) reliability of the narrow-pitched Cu lines. The fully-scaled-down, 65 nm-node Cu interconnects with the porous-on-rigid SiOCH hybrid structure achieve excellent performance and reliability.