| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor device which can suppress leakage current and achieve high breakdown voltage.SOLUTION: A semiconductor device comprises a MOS gate structure provided on a surface side of a silicon carbide semiconductor base substrate in which an n type silicon carbide epitaxial layer 2 is deposited on an ntype silicon carbide substrate 1. The MOS gate structure includes a p type base region 3 composed of a first p type base region 3a, a second p type base region 3b and a third ptype base region 3c, which have impurity concentrations different from each other and contact one another. The first p type base region 3a is arranged to be exposed on the surface of the base substrate. The second p type base region 3b is arranged to be opposite to the first p type base region 3a in a depth direction. The third ptype base region 3c is selectively provided inside the second p type base region 3b so as to be sandwiched by the first and second p type baser regions 3a, 3b. A circumference of a rear face side of the third ptype base region 3c is surrounded by the second p type base region 3b.SELECTED DRAWING: Figure 1 |
