Patent ID: 8072030

Claim:
A semiconductor device connected to a protected device and protecting the protected device by using a portion between a source terminal and a drain terminal as a discharge path, the semiconductor device comprising: an insulating film; a semiconductor layer provided on the insulating film; a plurality of source layers which are formed in the semiconductor layer and extends in a first direction; a plurality of drain layers which are formed in the semiconductor layer and extends along with the source layers; a plurality of body regions which are provided between the source layers and the drain layers in the semiconductor layer and extends in the first direction; and a plurality of body connecting parts respectively connecting the plurality of body regions, wherein a first width between the source layers and the drain layers at a first position is larger than a second width between the source layers and the drain layers at a second position, the second position is closer to the body connecting parts than the first position, widths at middle parts of the body regions are larger than widths at ends of the body regions.