SEMICONDUCTOR DEVICE MANUFACTURING METHOD AND SEMICONDUCTOR DEVICE

摘要

PROBLEM TO BE SOLVED: To manufacture a more favorable structure where a high-concentration impurity region, a middle-concentration impurity region and a low-concentration impurity region are arranged from a surface side of a substrate.SOLUTION: A manufacturing method of a semiconductor device 10 comprises: a first injection process of injecting a first conductivity type impurity from a surface 12b of a first conductivity type semiconductor substrate 12 into the semiconductor substrate 12; a process of fusing and subsequently solidifying a first semiconductor region 52 to the surface 12b from a specific depth 13b which is deeper than a depth 13a of a peak concentration of the first conductivity type impurity in an increase region 50 where a concentration of the first conductivity type impurity is increased in the first injection process and shallower than an end 13c of the increase region 50 on the deep side; a second injection process of injecting the first conductivity type impurity into a region shallower than the specific depth 13b; and a process of fusing and subsequently solidifying a region where a concentration of the first conductivity type impurity is increased in the second injection process.