Patent ID: 8581415

Claim:
A semiconductor integrated circuit device, comprising: a first interconnect formed over a main surface of a semiconductor substrate and including copper as a main component; a first barrier insulating film formed on a surface of the first interconnect so as to prevent diffusion of copper; a second barrier insulating film formed on a surface of the first barrier insulating film; a first interlayer insulating film formed on a surface of the second barrier insulating film; a second interconnect formed over the first interlayer insulating film and including copper as a main component; a third barrier insulating film formed directly on a surface of the second interconnect so as to prevent diffusion of copper; and a second interlayer insulating film formed directly on a surface of the third barrier insulating film, wherein the first barrier insulating film is formed between the first interconnect and the second barrier insulating film, wherein the second barrier insulating film is formed between the first barrier insulating film and the first interlayer insulating film, wherein each of the first and second barrier insulating films have a thickness that is smaller than a thickness of the first interlayer insulating film, wherein a thickness of the third barrier insulating film is smaller than a thickness of the second interlayer insulating film, wherein the first interlayer insulating film includes Si, O and C, wherein the second interlayer insulating film includes a silicon oxide film or a fluorinated silicon oxide film, and wherein a nitrogen concentration of the first barrier insulating film is larger than a nitrogen concentration of the second barrier insulating film.