SEMICONDUCTOR INTEGRATED CIRCUIT DEVICE

摘要

MV-PMOS (20) and MV-NMOS (30) constituting a high-side driver circuit are formed in an n partition region (2) formed on a p-type semiconductor substrate (1). MV-NMOS (30) is formed in a p-type partition region (3) of the midpoint potential (Vs) within the n-type partition region (2). An n-type epitaxial region (12) is formed outside the n-type partition region (2) of the surface layer of the p-type semiconductor substrate (1), and a pGND region (41) of a ground potential (GND) is formed on the exterior of the n-type epitaxial region (12). Between the p-type semiconductor substrate (1) and the n-type epitaxial region (12), there is provided a cavity (11) between the high-side driver circuit and the pGND region (41), and a p-type diffusion region (13) that reaches the cavity (11) through the n-type epitaxial region (12) is also provided. The midpoint potential (Vs) is impressed on the p-type partition region (3). This allows the incidence of malfunctioning and damage to be avoided, and chip size to be reduced.