US Patent 7713868 Strained metal nitride films and method of forming

A method for forming a strained metal nitride film and a semiconductor device containing the strained metal nitride film. The method includes exposing a substrate to a gas containing a metal precursor, exposing the substrate to a gas containing a nitrogen precursor activated by a plasma source at a first level of plasma power and configured to react with the metal precursor with a first reactivity characteristic, and exposing the substrate to a gas containing the nitrogen precursor activated by the plasma source at a second level of plasma power different from the first level and configured to react with the metal precursor with a second reactivity characteristic such that a property of the metal nitride film formed on the substrate changes to provide the strained metal nitride film.