Patent ID: 8883637

Claim:
A method for filling a recessed feature of a substrate, comprising: a) providing a substrate including a dielectric layer, a liner/barrier layer, and a recessed feature; b) at least partially filling the recessed feature of the substrate with tungsten-containing film using at least one of chemical vapor deposition (CVD) and atomic layer deposition (ALD); c) at a predetermined temperature less than or equal to 150° C., using an etchant including activated fluorine species to selectively etch the tungsten-containing film in the recessed feature at an etch rate that is higher than an etch rate of the liner/barrier layer, wherein the etching exposes at least a portion of the liner/barrier layer in the recessed feature and does not remove all of the tungsten-containing film at a bottom of the recessed feature; d) repeating (b) and (c) one or more times, wherein, during a first iteration of (c), the etching removes the tungsten-containing film in the recessed feature to a level that is below a field region of the dielectric layer; and e) filling the recessed feature using at least one of CVD and ALD.