A semiconductor device according to an embodiment of the present invention includes a semiconductor substrate; a wiring formed in predetermined pattern above the semiconductor substrate, a first insulating film lying right under the wiring, and a second insulating film lying in a peripheral portion other than a portion right under the wiring, in which a surface layer of the first insulating film lying in a boundary surface between the first insulating film and the second insulating film is chemically modified to reinforce the surface layer.