Patent ID: 8071478

Claim:
A method of controlling the resistivity and morphology of a tungsten film, comprising: (a) positioning a substrate in a process chamber; (b) during a first deposition stage, depositing a first film of a bulk tungsten layer by: (i) introducing a continuous flow of a reducing gas and a pulsed flow of a tungsten-containing compound to the process chamber to deposit tungsten on a surface of the substrate, (ii) flowing the reducing gas without flowing the tungsten-containing compound into the chamber to purge the chamber, and (iii) repeating steps (i) through (ii) until the first film fills vias in the substrate surface; (c) increasing the pressure in the process chamber; and (d) during a second deposition stage after the first deposition stage, depositing a second film of the bulk tungsten layer by introducing a continuous flow of reducing gas and tungsten-containing compound to the process chamber until a second desired thickness is deposited.