A novel single damascene process for via metal corrosion-free interconnects in advanced nodes

Via metal corrosion during via CMP is one of the major process challenges for S/D (single damascene) interconnects. Thus, the detailed mechanism of via metal corrosion during via CMP have been investigated and a novel via process has been proposed to demonstrate via metal corrosion-free S/D interconnects. The via metal corrosion-free S/D interconnect could achieve improved viachain yield and enhanced EM (electromigration) performance compared to D/D (dual damascene) interconnect due to an ideal via profile and better Cu fill capability.