A novel copper interconnection technology using self aligned metal capping method

A self aligned metal capping process for Copper damascene interconnect is newly developed in this study. A tungsten capping layer is selectively formed on the Cu interconnect using the preferential deposition phenomenon of W-CVD assisted by pre and post treatment. This technology is applied to 0.2 /spl mu/m bipolar-CMOS LSI with multilevel Cu interconnects, and then yield, reliability and operation speed are evaluated.