SEMICONDUCTOR DEVICE HAVING A REDUCED SURFACE FIELD STRENGTH

摘要

PHN. 9837 19 A semiconductor device of the "RESURF" type having a substrate region and a superimposed semiconductor layer which forms a p-n junction with the substrate region. The semiconductor layer has an islandshaped region which is depleted at least locally up to the surface at a reverse voltage applied across the p-n junction which is well below the breakdown voltage of the p-n junction. According to the invention the island-shaped part of the semiconductor layer over at least the part of its area, which may be depleted up to the surface, has a doping profile in vertical direction with at least two overlying layer portions and with different average not doping concentrations and of the same or opposite conductivity type, so as to increase the current-carrying capacity of the semiconductor layer.