A multiple step chemical vapor deposition process for depositing a tungsten layer on a substrate. A first step of the deposition process includes a nucleation step in which WF.sub.6 and SiH.sub.4 are introduced into a deposition chamber. Next, the flow of WF.sub.6 and SiH.sub.4 are stopped and diborane is introduced into the chamber for between 5-25 seconds. Finally, during a bulk deposition step, the WF.sub.6 is reintroduced into the chamber along with H.sub.2 and B.sub.2 H.sub.6 flows to deposit a tungsten layer on the substrate. In a preferred embodiment, the bulk deposition step also introduces nitrogen into the process gas.