Metallization opportunities and challenges for future back-end-of-the-line technology

Abstract

As scaling continues on copper interconnect technology, there are challenges to determine if the conventional damascene approach will still be viable and opportunities to consider other metallization, at the first few interconnect metal levels. As one example of the challenges, will electroplating, bottom-up fill, still be operable at dimensions of 10-15 nm, after barrier and seed layer deposition? In terms of opportunities, there are other metals which have lower electron mean free paths compared to copper and better electromigration resistance, that can be considered, with the trade off being higher bulk resistivity. Some of these challenges and opportunities are discussed.