Patent ID: 6924183

Claim:
A method of manufacturing an SOI semiconductor device, comprising steps of: providing an SOI substrate having a support substrate, a first insulation film and a semiconductor layer, the semiconductor layer being formed on the support substrate via the first insulation film; forming at least one transistor and an element isolation region on the semiconductor layer in the SOI substrate; covering the at least one transistor and the element isolation region with a second insulation film; forming a first opening section which penetrates the second insulation film, the element isolation region and the first insulation film to expose the support substrate; forming a first source interconnect, a first drain interconnect, and a first gate interconnect which are electrically connected to the at least one transistor, and forming dummy interconnects which are connected with the first source interconnect, first drain interconnect and first gate interconnect and are electrically connected with the support substrate via the first opening section, on the second insulation film; and disconnecting the dummy interconnects to electrically insulate the first source interconnect, first drain interconnect and first gate interconnect from the support substrate.