Patent ID: 6528403
Filing Date: 2003-03-04
Classification: H01L

Abstract:
A process for the fabrication of a semiconductor integrated circuit device, comprising the steps of:(a) forming a polysilicon film over a silicon-oxide-film-containing gate insulation film which has been formed over a silicon surface of a wafer; (b) forming a refractory metal film of tungsten or molybdenum over said polysilicon film through a medium of a barrier layer of a nitride of tungsten; (c) forming a gate electrode by patterning said polysilicon film and said refractory metal film; and (d) after said step (c), thermally oxidizing the polysilicon film without oxidizing said refractory metal film and said barrier layer, under a gas ambient containing (1) hydrogen, and (2) water vapor synthesized from a mixed gas of oxygen and hydrogen gases by a platinum catalyst, and containing substantially no hydrogen radicals, the partial pressure of the water vapor being lower than that of the hydrogen in the gas ambient.