Sputtered tungsten diffusion barrier for improved interconnect robustness

A method of forming inter-level contacts or vias between metal layers using a tungsten film deposited into the via using non-collimated sputter deposition. The sputter chamber is configured with a pressure of about 1 mTorr to about 10 mTorr with an inert gas flow of at least at least 25 cm3/min to about 150 cm3/min. Shielding inside the chamber is coated with a material, preferably, aluminum oxide, that promotes adhesion of tungsten to the shielding. An adhesion layer of titanium may be included prior to deposition of the tungsten film. Non-collimated sputter deposition increases the target to substrate distance inside the sputter chamber; reduces the heating effect associated with traditional collimated sputtering; and provides more robust diffusion barriers.