Patent ID: 8252628

Claim:
A method of manufacturing a semiconductor device, comprising the steps of: providing a semiconductor substrate which has oppositely facing first and second surfaces; forming an electronic element on the first surface that is an active surface of the semiconductor substrate and forming a pad electrode to be connected to the electronic element in a peripheral portion of the electronic element on the active surface; forming a first opening to extend from the second surface of the semiconductor substrate toward the pad electrode so as not to reach the first surface of the semiconductor substrate; forming a second opening having a diameter smaller than that of the first opening to reach the pad electrode from a bottom surface of the first opening; covering sidewall surfaces of the first opening and the second opening to form an insulating layer; and covering at least an inner wall surface of the insulating layer and a bottom surface of the second opening to form a conductive layer, wherein, the step of forming the second opening includes using laser irradiation to position the second opening with respect to the first opening such that if the first opening is misaligned with respect to the pad electrode, the second opening is positioned within an area of overlap between the first opening and the pad electrode.