Deposition of WN/sub x/C/sub y/ thin films by ALCVD/spl trade/ method for diffusion barriers in metallization

A new process of depositing ternary tungsten nitride carbide WN/sub x/C/sub y/ films as a diffusion barrier material for copper metallization has been developed with the atomic layer chemical vapor deposition (ALCVD/spl trade/) technology. The growth temperature was varied from 300 to 350/spl deg/C, and the resistivity was in a range of 300-400 /spl mu//spl Omega/cm for a /spl sim/25 nm film. The film composition was influenced by deposition conditions with a W, N and C content of approximately 55, 15, and 30 at.%, respectively. Impurities such as F, O, and B in the bulk of the film were low, less than 1 at.% or under the detection limit of analysis tools used. The deposited films showed excellent compatibility with different substrates including Cu, SiO/sub 2/, SiC, Si/sub x/N/sub y/, SiLK and Aurora. Preliminary electrical tests of WN/sub x/C/sub y/ on the dual damascene wafers showed promising results.