Patent ID: 8035215

Claim:
A semiconductor device comprising: a semiconductor substrate having a hole penetrating through a thickness thereof, the hole having a first end at a back surface of the substrate and a second end at a front surface of the substrate; a first insulation film disposed on the front surface and having an opening overlapping with the hole of the substrate, the opening of the first insulation film being smaller than the second end of the hole; a pad electrode for external connection disposed on the first insulation film so as to cover the opening of the first insulation film; a second insulation film disposed on a sidewall of the hole of the substrate and the back surface of the substrate; and a second wiring disposed in the hole so as to be in contact with the pad electrode, the first insulation film and the second insulation film, wherein a part of the second insulation film is disposed so as to bend at a juncture between the sidewall of the hole and the first insulation film so as to extend, in a plane parallel to the first insulation film, along a portion of the first insulation film toward the opening of the first insulation film, and the bending part of the second insulation film is within the second end of the hole of the substrate and placed between the second wiring and the first insulation film so as to form a three-layer vertical stack of the first insulation film, the second insulation film and the second wiring, the semiconductor device is configured to be an operable individual die, and the hole of the semiconductor device is located at the pad electrode so that the pad electrode closes the second end of the hole in the semiconductor substrate.