The semiconductor drift device comprises a deep well of a first type of electrical conductivity provided for a drift region in a substrate of semiconductor material, a drain region of the first type of conductivity at the surface of the substrate, a plurality of source regions of the first type of conductivity in shallow wells of the first type of conductivity at the periphery of the deep well of the first type, and a deep well or a plurality of deep wells of an opposite second type of electrical conductivity provided for a plurality of gate regions at the periphery of the deep well of the first type. The gate regions are formed by shallow wells of the second type of electrical conductivity, which are arranged in the deep well of the second type between the shallow wells of the first type.