Semiconductor device and method of manufacturing the same

摘要

A semiconductor device includes a p^--silicon substrate, n^--epitaxial growth layers on the p^--silicon substrate, a field insulating film at the surface of the n^--epitaxial growth layer, an npn transistor formed at the n^--epitaxial growth layer, an pnp transistor formed at the n^--epitaxial growth layer, a DMOS transistor on the n^--epitaxial growth layer, and a resistance. The DMOS transistor includes an n⁺-diffusion layer forming a source, a p-type diffusion layer forming a back gate region, a lightly doped n-type diffusion layer forming a drain, and a heavily doped n⁺-diffusion layer forming the drain.