Method of manufacturing a semiconductor device of the mis type

A method for manufacturing a semiconductor device of the invention comprises the steps of (a) forming a gate insulating film (3, 23, 33, 43, 53, 63) on a surface of a silicon substrate (1,21,31,41,51,61), and a gate electrode (4, 24, 34, 44, 54, 64) on said gate insulating film (3, 23, 33, 43, 53, 63);(b) forming a self-aligned insulating film (6, 26a, 38, 46, 55, 65) at least on a side wall of said gate electrode (4, 24,34, 44, 54, 64);(c) forming a self-aligned metal or metal silicide film (9, 29,39,49, 57a, 57b, 57c, 67a, 67b, 67c) on a region on which an insulating film is not formed, said region including a source region (5a, 25a, 35a, 48a, 58a, 68a), a drain region (5b, 25b, 35b, 48b, 58b, 68b) and a diffusion interconnection region (5c, 25c, 35c, 48c) which is an extended part of at least one of said source region and said drain region, or prospective regions for said source, drain and diffusion interconnection regions; and(d) forming said source region, said drain region and said diffusion interconnection region which is the extended part of at least one of said source region and said drain region, by doping at least one time said substrate with an impurity which has a conductivity type opposite to a conductivity type of said silicon substrate any time after step (a).