Blakely Sokoloff Taylor & Zafman
Method of forming barrier layer for tungsten plugs in interlayer dielectrics
 A method of reducing tungsten plug loss in processes for fabrication for silicon-based semiconductor devices that include a tungsten plug in a high aspect ratio contact hole. The invention provides a barrier layer prepared by first forming a conformal layer of titanium nitride by chemical vapor deposition. Afterward, another film of titanium nitride is supplied by plasma vapor deposition. The barrier layer comprises at least these two films, and tungsten is then deposited to at least fill the high aspect ratio film-coated contact hole. Upon removal of excess tungsten as by wet etch back, the tungsten plug remains essentially intact, and any plug loss is insignificant in comparison with the prior art. 
Worldwide Semiconductor Manufacturing Corporation
H H
H01L H01L
inventional inventional
Sung Chun Sen-Nan Wen-Yu Hui-Lun
Hsieh Lee Ho Chen