SEMICONDUCTOR DEVICE AND MANUFACTURING METHOD OF THE SAME

摘要

PROBLEM TO BE SOLVED: To provide an art to improve both of breakdown voltage and on-resistance in a semiconductor device having a p-type semiconductor region which contacts a bottom face of a trench gate.SOLUTION: A semiconductor device 1 comprises a p-type semiconductor region 15 which contacts a bottom face 30b of a trench gate 30. The p-type semiconductor region 15 has a first p-type semiconductor region 15a containing boron as a p-type impurity and a second p-type semiconductor region 15b containing aluminum as a p-type impurity. The first p-type semiconductor region 15a is arranged closer to the trench gate 30 than the second p-type semiconductor region 15b. When observed along a depth direction, the second p-type semiconductor region 15b is arranged so to be within a part of a presence range of the first p-type semiconductor region 15a. A diffusion coefficient of boron is larger than a diffusion coefficient of aluminum.SELECTED DRAWING: Figure 1