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

摘要

We address contact plug structure with low resistance applicable to NiSi system. It consists of thin barrier layer, prepared by NH3 plasma nitrization of PE-TiCl4 CVD Ti (PE-TiN/Ti) at process temperature of 450°C, and W-plug with B2H6 based nucleation layer. This process enables us to reduce contact resistance down to 50% without “volcano” type defect issues due to WF6 attacking.