Disclosed is a semiconductor device that includes: a semiconductor substrate; a first insulating film formed above the semiconductor substrate and having a relative dielectric constant of 3.8 or less; a conductor which covers a side face of the first insulating film at least near four corners of the semiconductor substrate, and at least an outer side face of which has a conductive barrier layer; and a second insulating film covering the outer side face of the conductor and having a relative dielectric constant of over 3.8. Also disclosed is a semiconductor device that includes: a conductor covering a side face of the first insulating film at least near four corners of the semiconductor substrate; and a corrosion resistant conductor formed at least near the four corners of the semiconductor substrate to extend from directly under the second insulating film to directly under the conductor.