In-situ Formation of a Copper Silicide Cap For TDDB and Electromigration Improvement

Self-aligned barrier processes are being investigated as an alternative to standard dielectric barrier processes for the 65 nm technology nodes and beyond. Variations in the dielectric barrier process can modulate the copper-dielectric interface and the SiC/low k interface to improve dielectric and electromigration reliability. For the first time, in this paper, we will show that optimization of both the self aligned barrier and the SiC film can improve the adhesion between both the Cu and the dielectric layer on top, resulting in a 10-1000times increase in time-dependent dielectric breakdown lifetime