| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor device which can ensure both of voltage withstanding of a HVIC (High Voltage Integrated Circuit) and current capacity of a pchMOSFET in an optimum state.SOLUTION: A semiconductor device comprises: an ntype diffusion region 1 which surrounds a high-side well region 112 and electrically separated from a low-side region; and first and second p-type diffusion regions 2a, 2b provided in the ntype diffusion region 1 at a distance from each other. The first p type diffusion region 2a composes a double RESURF structure of an nchMOSFET 105 of a level increasing level shift circuit 104 and a high-voltage junction termination structure 111. The second p type diffusion region 2b composes a double RESURF structure of a pchMOSFET 108 of a level decreasing level shift circuit. An impurity concentration of the ntype diffusion region 1 is not less than 1.3×10/cmand not more than 2.8×10/cm. An impurity concentration of each of the first and second p type diffusion regions 2a, 2b is not less than 1.1×10/cmand not more than 1.4×10/cm. |
