Advanced 5nm BEOL integration development for manufacuring

This paper describes an advanced 5nm node back-end-of-line (BEOL) process integration based on an extreme ultraviolet (EUV) lithography process, atomic layer deposition (ALD) barrier metal (BM) and Cu reflow process. The ALD BM technology was integrated into Low-k in the damascene metallization. This advanced BEOL integration showed a good RC (resistance-capacitance) performance within +3% and an excellent 46% reduction in the via resistance compared to the physical vapor deposition (PVD) BM, and satisfied the reliability requirement for the time-dependent dielectric breakdown (TDDB) and the electro-migration (EM). Finally, ALD BM and Cu reflow process were developed for the advanced 5nm node BEOL integration, and the new process is implemented in order to achieve low via resistance and better device performance.