SEMICONDUCTOR DEVICE INCLUDING ELECTROSTATIC DISCHARGE PROTECTION CIRCUIT

A SGPMOS transistor includes a base, a P-type diffusion layer, a gate electrode, and a LOCOS oxide film. The base includes at least one of a N-type semiconductor substrate, a P-type semiconductor substrate, and a N-type well. The P-type diffusion layer includes a P-type source and a P-type drain. At least the P-type drain includes a double diffusion structure including first and second P-type drain diffusion layers. The LOCOS oxide film is provided on the first P-type drain diffusion layer and covered by an end of the gate electrode. The first and the second P-type drain diffusion layers satisfy a relation of Y