Robust ultrathin (20-25 nm) trilayer dielectric low k Cu damascene cap for sub-30 nm nanoelectronic devices

Abstract

Robust ultrathin (20 nm) trilayer low k SiNx/SiNy/SiCNH dielectric Cu caps (k ∼4.0-4.2) with post ultraviolet (UV) cure compressive stress were developed and integrated into 22nm CMOS Back End Of Line (BEOL) devices. The new cap reduces device's capacitance (∼ 4%) and enhances stress stability in Cu-Ultra low k structures. ©The Electrochemical Society.