Methods for depositing tungsten layers employing atomic layer deposition techniques

Abstract

In one embodiment of the invention, a method for forming a tungsten-containing layer on a substrate is provided which includes positioning a substrate containing a barrier layer disposed thereon in a process chamber, exposing the substrate to a first soak process for a first time period and depositing a nucleation layer on the barrier layer by flowing a tungsten-containing precursor and a reductant into the process chamber. The method further includes exposing the nucleation layer to a second soak process for a second time period and depositing a bulk layer on the nucleation layer. In one example, the barrier layer contains titanium nitride, the first and second soak processes independently comprise at least one reducing gas selected from the group consisting of hydrogen, silane, disilane, dichlorosilane, borane, diborane, derivatives thereof and combinations thereof and the nucleation layer may be deposited by an atomic layer deposition process or a pulsed chemical vapor deposition process while the bulk layer may be deposited by a chemical vapor deposition process or a physical vapor deposition process.