Provided are a semiconductor device and a manufacturing method therefor that can prevent the breakage of an element and in which the control of impurity amounts is less susceptible to variations in manufacturing processes. A semiconductor substrate has a front surface and includes hole portions extending from the front surface to an inside of the substrate. N-type regions are formed in the semiconductor substrate. At wall surfaces of the hole portions, p-type regions are formed to configure p-n junction with the n-type regions. Each of the p-type regions includes a low-concentration region and a high-concentration region formed at the wall surface of each hole portion. 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.