Patent ID: 6235632
Filing Date: 2001-05-22
Classification: H01L

Abstract:
A method of fabricating a tungsten plug at the via level comprising the steps of:forming a metal line in a top portion of a first insulating layer;forming a second insulating layer on said first insulating layer and over an exposed surface of said metal line;applying an etching process to a region of said second insulating layer formed over the exposed surface of said metal line to create a contact hole within said region, said metal line being exposed at the region;depositing in a plasma-enhanced CVD chamber a tungsten nitride thin film with a thickness of 50 .ANG. to 1,000 .ANG. over said second insulating layer and said exposed metal line;said step of depositing tungsten nitride includes the step of injecting a reactant gas mixture containing WF.sub.6, NF.sub.3, and H.sub.2 ;depositing in situ in the same CVD chamber a blanket tungsten thin film to fill the contact hole and to form a planar layer successively to the depositing of said tungsten nitride thin film; andapplying a chemical-mechanical polishing to polish said tungsten nitride thin film and said blanket tungsten thin film until the upper surface of said second insulating layer is exposed.