An improved SIV resistance and an improved EM resistance are achieved in the coupling structure containing copper films. A semiconductor device includes: a semiconductor substrate; a second insulating layer formed on or over the semiconductor substrate; a second barrier metal film, formed on the second insulating film, and being capable of preventing copper from diffusing into the second insulating film; and an electrically conducting film formed on the second barrier metal film so as to be in contact with the second barrier metal film, and containing copper and carbon, wherein a distribution of carbon concentration along a depositing direction in the second electrically conducting film includes a first peak and a second peak.