Semiconductor device having a device formation region protected from a counterelectromotive force

Abstract

A semiconductor device includes an epitaxial layer formed on a P type silicon substrate; a P+ diffusion layer for dividing the epitaxial layer into an N− epi layer, which constitutes a device formation region, and an N− epi layer, which constitutes an invalid area; and an aluminum wire for electrically connecting the N− epi layer (invalid area) to the P+ diffusion layer. Since the potential of the N− epi layer (invalid area) can be made equal to that of the P+ diffusion layer, it is possible to prevent the electron supply from the P+ diffusion layer to the invalid area even when electrons are supplied to the device formation region by a counterelectromotive force produced by a load having an inductance L.

Dependencies are inferred from the claim text.