Embodiments of the invention provide a method for depositing tungsten-containing materials. In one embodiment, a method includes forming a tungsten nucleation layer over an underlayer disposed on the substrate while sequentially providing a tungsten precursor and a reducing gas into a process chamber during an atomic layer deposition (ALD) process and depositing a tungsten bulk layer over the tungsten nucleation layer, wherein the reducing gas contains hydrogen gas and a hydride compound (e.g., diborane) and has a hydrogen/hydride flow rate ratio of about 500:1 or greater. In some examples, the method includes flowing the hydrogen gas into the process chamber at a flow rate within a range from about 1 slm to about 20 slm and flowing a mixture of the hydride compound and a carrier gas into the process chamber at a flow rate within a range from about 50 sccm to about 500 sccm.