Low contact-resistance metallization process for a nickel self-aligned contact of beyond 65nm node CMOS

We address contact plug structure with low resistance applicable to NiSi system. It consists of thin barrier layer, prepared by NH 3 plasma nitrization of PE-TiCU CVD Ti (PE-TiN/Ti) at process temperature of 450degC, and W-plug with B 2 H 6 based nucleation layer. This process enables us to reduce contact resistance down to 50% without "volcano" type defect issues due to WF 6 attacking.