SEMICONDUCTOR DEVICE AND MANUFACTURING METHOD OF THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a semiconductor device which has improved voltage withstanding characteristics and reduced on-resistance; and provide a manufacturing method of the semiconductor device.SOLUTION: MOSFET 1 comprises: a substrate 10 in which a first trench 17 opens on a principal surface 10A side, and which is composed of a silicon carbide; a gate insulation film 20; and a gate electrode 30. The substrate 10 includes: an n-type source region 15 including the principal surface 10A of the substrate 10 and a wall surface 17A of the first trench 17; a p-type body region 14 which contacts the source region 15 and includes the wall surface 17A of the first trench 17; an n-type drift region 13 which contacts the body region 14 and includes the wall surface 17A of the first trench 17; and a p-type deep region 16 which contacts the body region 14 and extends to a region deeper than the first trench 17. The first trench 17 is formed such that a distance between the wall surface 17A and the deep region 16 increases with distance from the principal surface 10A of the substrate 10.