Integration and performances of an alternative approach using copper silicide as a self-aligned barrier for 45 nm technology node Cu interconnects

Simulated signal propagation performances including crosstalk and delay time were investigated for self-aligned barriers on copper, highlighting the benefits of introducing these barriers for the 65 and 45 nm technology nodes. As an alternative to electrolessly deposited alloys, a self-aligned barrier technique based on controlled Si enrichment of Cu and named CuSiN was introduced. Promising performances in terms of copper barrier efficiency, interconnect compatibility, integration (line and via resistances, leakage currents, coupling capacitances), and reliability were shown.