Abstract: A gate electrode of a field-effect transistor used as a peripheral circuit is constituted by the same gate electrode structure as a double-level gate electrode structure of nonvolatile memory cells, and a contact hole for connecting those conductive films constituting the gate electrode is provided at a location which two-dimensionally overlaps an active area within a plane of the gate electrode.

Abstract: A gate electrode of a field-effect transistor used as a peripheral circuit is constituted by the same gate electrode structure as a double-level gate electrode structure of nonvolatile memory cells, and a contact hole for connecting those conductive films constituting the gate electrode is provided at a location which two-dimensionally overlaps an active area within a plane of the gate electrode.

Abstract: A plurality of connection holes 24 for connecting n+ type semiconductor region 20 of zener diodes (D1, D2) and wires 21 and 22 to each other are not arranged in the center of the n+ type semiconductor region 20, that is, in a region in which a p+ type semiconductor region 6 and the n+ type semiconductor region 20 form a junction but is arranged in the periphery which is deeper than the center in junction depth. In addition, these connection holes 24 are spaced from each other so that a pitch between the adjacent connection holes 24 is greater than a minimum pitch between connection holes of the circuit, and thereby a substrate shaving quantity is reduced when the respective connection holes 24 are formed by means of dry etching.