TUNGSTEN FILMS PRODUCED BY SELECTIVE DEPOSITION ONTO SILICON-WAFERS

Tungsten films were deposited selectively onto oxide-patterned silicon wafers via the hydrogen reduction of WF//6 at 285 degree C. The deposition rate of the films and the selective nature of the process were studied. The microstructure and crystallographic properties of the metallic layers were examined. The resistivity of the films was measured as a function of the film thickness. The morphology of the tungsten layers and W-Si interfaces was observed by scanning electron microscopy. The reactivity of tungsten with silicon and the formation of WSi//2 by interdiffusion during heat treatment of W/Si structures was investigated as a function of the annealing parameters.