| 主权项 |
1. A semiconductor device, comprising:
a substrate; a first circuit region that is formed on the substrate in which a first circuit whose power potential is a first voltage is formed; a separation region that surrounds the first circuit region; a second circuit region that is formed on the substrate, and located outside of the separation region in a plan view, in which a second circuit whose power potential is a second voltage lower than the first voltage; and a coupling transistor that is located in the separation region, couples the second circuit to the first circuit, and has a source and a drain of a first conductivity type, wherein the separation region includes: an element separation film formed on the substrate; a field plate electrode that overlaps with the element separation film in a plan view, and is repetitively disposed in a folded manner or a spiral shape in a direction along an edge of the first circuit region; a second conductivity type region that is disposed on the substrate, overlaps with the element separation film in a plan view, and is located around the coupling transistor; and a first conductivity region that is located on a side opposite to the source or the drain of the coupling transistor through the second conductivity type region, wherein a part of the field plate electrode overlaps with a part of the second conductivity type region, and wherein the field plate electrode is electrically coupled to a drain electrode of the coupling transistor at a portion located on the first circuit region side from a center thereof in a width direction of the separation region, and coupled to a ground potential or the second circuit at a portion located on the second circuit region side from the center. |
