Films of Ni-7 at% V, Pd, Pt and Ta-Si-N as diffusion barriers for copper on

Films of Ni-7 at% V, Pt, Pd, and , each approximately 100 nm thick, were magnetron-deposited and interposed between about 250 nm thick copper overlayers and single-crystalline substrates. The samples were then annealed in vacuum up to C. The performance of the metal and the tantalum-silicon-nitride films as diffusion barriers for in-diffusion of Cu and out-diffusion of Bi and Te was evaluated by 2.0 MeV backscattering spectrometry and x-ray diffraction. The Ni-7 at% V, Pd and Pt films all fail to prevent interdiffusion of Cu and after a few hours of annealing at C. However, the barrier preserves the integrity of the contact after C for 50 h and C for 1 h anneals. These results confirm the superior characteristics of the metal-silicon-nitride films as diffusion barriers.