Abstract: A semiconductor device, including a substrate, a first source/drain region, a second source/drain region, and a gate structure, is provided. The substrate has an extra body portion and a fin protruding from a top surface of the substrate, wherein the fin spans the extra body portion. The first source/drain region and the second source/drain region are in the fin. The gate structure spans the fin, is located above the extra body portion, and is located between the first source/drain region and the second source/drain region.

Abstract: An electrostatic discharge circuit is provided. The electrostatic discharge circuit includes a cascade transistor configuration and a control circuit. The cascade transistor configuration includes a first transistor and a second transistor coupled between a power supply node and a ground node. The control circuit is coupled to the cascade transistor configuration, and coupled between the power supply node and the ground node. The control circuit includes a voltage drop circuit coupled to the power supply node and the first transistor, and an electrostatic discharge detecting circuit between the voltage drop circuit and the ground node. The electrostatic discharge detecting circuit is coupled to the first transistor and the second transistor.