Abstract: Methods for reducing resistivity of metal gapfill include depositing a conformal layer in an opening of a feature and on a field of a substrate with a first thickness of the conformal layer of approximately 10 microns or less, depositing a non-conformal metal layer directly on the conformal layer at a bottom of the opening and directly on the field using an anisotropic deposition process. A second thickness of the non-conformal metal layer on the field and on the bottom of the feature is approximately 30 microns or greater. And depositing a metal gapfill material in the opening of the feature and on the field where the metal gapfill material completely fills the opening without any voids.

Abstract: A method and apparatus for forming tungsten features in semiconductor devices is provided. The method includes exposing a top opening of a feature formed in a substrate to a physical vapor deposition (PVD) process to deposit a tungsten liner layer within the feature. The PVD process is performed in a first processing region of a first processing chamber and the tungsten liner layer forms an overhang portion, which partially obstructs the top opening of the feature. The substrate is transferred from the first processing region of the first processing chamber to a second processing region of a second processing chamber without breaking vacuum. The overhang portion is exposed to nitrogen-containing radicals in the second processing region to inhibit subsequent growth of tungsten along the overhang portion. The feature is exposed to a tungsten-containing precursor gas to form a tungsten fill layer over the tungsten liner layer within the feature.

Abstract: A method and apparatus for tungsten gap-fill in semiconductor devices are provided. The method includes performing a gradient oxidation process to oxidize exposed portions of a liner layer, wherein the gradient oxidation process preferentially oxidizes an overhang portion of the liner layer, which obstructs or blocks top openings of one or more features formed within a field region of a substrate. The method further includes performing an etchback process to remove or reduce the oxidized overhang portion of the liner layer, exposing the liner layer to a chemical vapor transport (CVT) process to remove metal oxide remaining from the gradient oxidation process and the etchback process, and performing a tungsten gap-fill process to fill or partially fill the one or more features.