METHOD FOR FORMING ALL TUNGSTEN CONTACT AND LINE

PROBLEM TO BE SOLVED: To provide a novel low-resistivity tungsten film stack scheme and a method for depositing a low-resistivity tungsten film stack. SOLUTION: The film stack includes a tungsten rich layer 371 having tungsten mixed with a low resistivity tungsten compound, e.g., tungsten carbide or tungsten nitride, as a base for deposition of tungsten nucleation 373 and/or a bulk layer 375. These tungsten rich layers can be used as barrier and/or adhesion layers in tungsten contact metallization and bitlines. Deposition of the tungsten-rich layers involves exposing a substrate to a halogen-free organometallic tungsten precursor. The mixed tungsten/tungsten carbide layer is a thin and low resistivity film with excellent adhesion and a good base for subsequent tungsten plug or line formation. COPYRIGHT: (C)2009,JPO&INPIT