| 摘要 |
PURPOSE:To prevent the mutually electrical interference by electrically separating one conductive type FET substrate and the other conductive type semiconductor substrate. CONSTITUTION:A semiconductor device includes a P-type semiconductor substrate 70 and a P-type semiconductor region 71 for separating the interface between mutual devices. In a PMOS 43, drain and source regions are formed by a P<+> diffusion layers 74 and 75 using an N-type epitaxial layer 73 formed on the P-type semiconductor substrate 70 as a substrate. In the N-type epitaxial layer 73 serving as the substrate of the PMOS 43, an ohmic contact is formed by an N<+> diffusion layer 76, and the epitaxial layer 73 is connected to a power source 42. In an NMOS 44, a well region 80 is formed on the N-type epitaxial layer 73 by a P-type diffusion, and a source 81 and a drain 82 are formed in the well region 80 by an N<+> diffusion. In the P-type well 80 serving as the substrate of the NMOS 44, an ohmic contact is formed by a P<+> diffusion layer 83, and the well 80 is connected to a ground potential. The P-type semiconductor region 80 serving as the substrate of the NMOS 44 can be formed by electrically separting the region 80 from the P-type semiconductor substrate 70 by the N-type semiconductor region 73. |
