Patent ID: 6329274
Filing Date: 2001-12-11
Classification: H01L

Abstract:
A method of producing a semiconductor device, comprising:a) forming an impurity diffusion region having a conductivity type in a surface of a semiconductor substrate;b) forming an insulating film on the surface of the substrate so that the insulating film covers at least part of the impurity diffusion region;c) forming a photoresist film on the insulating film;d) patterning the photoresist film to provide the photoresist film with an opening above the impurity diffusion region;e) etching the insulating film using the patterned photoresist film as a mask to form a contact hole in the insulating film at the location of the opening in order to expose a part of the impurity diffusion region;f) removing the patterned photoresist film;g) removing a natural oxide film from a surface of the impurity diffusion region in the contact hole by reducing with a reactive gas at an ambient temperature of 600-1000.degree. C. so as to effect gas-phase etching to activate an exposed surface of the impurity diffusion region;h) applying a gas containing an impurity component which has same conductivity type as that of the impurity diffusion region to the surface of semiconductor substrate and heating the semiconductor substrate at a temperature of 600-900.degree. C. to form an impurity film which contains the impurity component and is adsorbed on the activated exposed surface of the impurity diffusion region and in the contact hole;i) annealing the impurity diffusion region and the impurity film to diffuse the impurity component from the impurity film to a depth into the impurity diffusion region; andj) filling the contact hole with an electrically conductive layer to produce electrical contact between the impurity diffusion region and the electrically conductive layer via the impurity film.