SEMICONDUCTOR DEVICE HAVING DEVICE ELEMENT STRUCTURES WITH PN JUNCTION FORMED IN ACTIVE REGION AND VOLTAGE WITHSTANDING RINGS FORMED IN PERIPHERY REGION SURROUNDING THE ACTIVE REGION AND METHOD OF MANUFACTURING SEMICONDUCTOR DEVICE

A semiconductor substrate is fabricated in which only first and second n−-type epitaxial layers are stacked on an n+-type starting substrate, a front surface of the substrate being a continuously flat surface from an active region to a chip end. In an edge termination region, as a voltage withstanding structure, a ring-shape FLR is provided in which p-type FLR regions concentrically surrounding a periphery of the active region are disposed apart from one another. The p-type FLR regions each have a layered structure configured by multiple p-type regions (partial FLRs) that are adjacent to one another in a depth direction and formed by ion implantation of a p-type impurity for the first and the second n−-type epitaxial layers configuring the substrate. A predetermined breakdown voltage is obtained by adjusting the number of stacked layers and impurity concentrations of the partial FLRs of the p-type FLR regions.