摘要 |
In a semiconductor device of the present invention, an N-type buried diffusion layer is formed across a substrate and an epitaxial layer. A P-type buried diffusion layer is formed across an upper surface of the N-type buried diffusion layer over a wide range to form a PN junction region for an overvoltage protection. A P-type diffusion region is formed so as to be connected to the P-type buried diffusion layer. A breakdown voltage of the PN junction region is lower than a breakdown voltage between a source and a drain. This structure makes it possible to prevent a concentration of a breakdown current and protect the semiconductor device from an overvoltage.
|