OMCVD TiN diffusion barrier for copper contact and via/interconnects structures

Titanium nitride (TiN) layers are currently used both as diffusion barriers and as glue layers for poorly adhering materials in the semiconductor industry. Until recently titanium nitride was deposited by PVD method with a poor step coverage. Some TiN CVD methods were developed but present drawbacks (chlorides contamination, high resistivity). A new CVD process is now developed with a desirable step coverage and a low resistivity. This one consists of a sequential OMCVD-plasma treatment process allowing a deposition of films with resistivity lower than 300 /spl mu//spl Omega/.cm. The present paper deals with TiN performances as barrier materials for copper integration in dual damascene architecture.