Abstract
A 5 nm-thick (AlCrTaTiZrRu)N 0.5 film with senary metallic elements and 33 at% N was developed as a diffusion barrier by reactive sputtering. The interdiffusion of Si and Cu through the layer at 700 to 900 °C was characterized. The as-deposited (AlCrTaTiZrRu)N 0.5 film had an amorphous structure dispersed with a few nanocrystallites. After annealing at 700 and 800 °C, the electrical resistance of Si/(AlCrTaTiZrRu)N 0.5 /Cu film stacks remained low. A very limited amount of Cu diffused into the (AlCrTaTiZrRu)N 0.5 layer at 800 °C, but any further Cu diffusion into the Si substrate was retarded by the barrier, suggesting the high temperature endurance of the 5-nm (AlCrTaTiZrRu)N 0.5 layer. Only at 900 °C the (AlCrTaTiZrRu)N 0.5 barrier layer failed; severe interdiffusion of Si and Cu through the layer occurred, and a large amount of Cu silicides then formed. Copyright © 2011 American Scientific Publishers.