Semiconductor device and manufacturing method therefor

A method for manufacturing a semiconductor device, comprising the steps of:

• forming a first impurity region of a first conductive type in a semiconductor substrate;
• forming a hole portion at a front surface of the semiconductor substrate;
• and
• forming a second impurity region of a second conductive type by implanting ions at a plurality of different angles relative to the hole portion in a planar view, the second impurity region including a low-concentration region of a second conductive type positioned at a wall surface of the hole portion, and a high-concentration region of the second conductive type positioned at the wall surface of the hole portion and coupled to the low-concentration region, the second impurity region forming p-n junction with the first impurity region,
• wherein the high-concentration region is formed such that a width of the high-concentration region along the wall surface of the hole portion becomes smaller from the front surface toward a deeper position.