A method comprising: forming a layer stack with a plurality of first layers of a first doping type and a plurality of second layers of a second doping type complementary to the first doping type on top of a carrier, wherein the first layers and the second layers are arranged alternatingly within the layer stack, forming the layer stack comprises forming a plurality of epitaxial layers (140 n) on the carrier, forming each of the plurality of epitaxial layers (140 n) comprises depositing a layer of semiconductor material, forming at least two first implantation regions of one of said first doping type or said second doping type at different vertical positions of the respective layer of semiconductor material, and forming at least one second implantation region of the doping type that is complementary to the doping type of the first implantation regions, wherein the first implantation regions and the second implantation regions are arranged alternatingly, wherein forming implantation regions of the first doping type comprises implanting ions of the first doping type, forming implantation regions of the second doping type comprises implanting ions of the second doping type; and heating the epitaxial layers (140 n) with the implantation regions (111, 121) formed therein, thereby diffusing the implanted ions and the first implantation regions forming the first layers and the second implantation regions forming the second layers, wherein if two or more of the first layers are formed within the same epitaxial layer, the different first layers within the respective epitaxial layer have different thicknesses (x 11, x 12), the thickness decreasing towards the top of the layer stack; if two or more of the second layers are formed within the same epitaxial layer, the different second layers within the respective epitaxial layer have different thicknesses (x 21, x 22), the thickness decreasing towards the top of the layer stack; and the doping type of the topmost implantation region (111, 121) of an epitaxial layer (140 n) differs from the doping type of a directly adjoining lowermost implantation region (111, 121) of a subsequent epitaxial layer. the first layers and the second layers are arranged alternatingly within the layer stack, forming the layer stack comprises forming a plurality of epitaxial layers (140 n) on the carrier, forming each of the plurality of epitaxial layers (140 n) comprises depositing a layer of semiconductor material, forming at least two first implantation regions of one of said first doping type or said second doping type at different vertical positions of the respective layer of semiconductor material, and forming at least one second implantation region of the doping type that is complementary to the doping type of the first implantation regions, wherein the first implantation regions and the second implantation regions are arranged alternatingly, wherein forming implantation regions of the first doping type comprises implanting ions of the first doping type, forming implantation regions of the second doping type comprises implanting ions of the second doping type; and forming implantation regions of the first doping type comprises implanting ions of the first doping type, forming implantation regions of the second doping type comprises implanting ions of the second doping type; and heating the epitaxial layers (140 n) with the implantation regions (111, 121) formed therein, thereby diffusing the implanted ions and the first implantation regions forming the first layers and the second implantation regions forming the second layers, wherein if two or more of the first layers are formed within the same epitaxial layer, the different first layers within the respective epitaxial layer have different thicknesses (x 11, x 12), the thickness decreasing towards the top of the layer stack; if two or more of the second layers are formed within the same epitaxial layer, the different second layers within the respective epitaxial layer have different thicknesses (x 21, x 22), the thickness decreasing towards the top of the layer stack; and the doping type of the topmost implantation region (111, 121) of an epitaxial layer (140 n) differs from the doping type of a directly adjoining lowermost implantation region (111, 121) of a subsequent epitaxial layer. if two or more of the first layers are formed within the same epitaxial layer, the different first layers within the respective epitaxial layer have different thicknesses (x 11, x 12), the thickness decreasing towards the top of the layer stack; if two or more of the second layers are formed within the same epitaxial layer, the different second layers within the respective epitaxial layer have different thicknesses (x 21, x 22), the thickness decreasing towards the top of the layer stack; and the doping type of the topmost implantation region (111, 121) of an epitaxial layer (140 n) differs from the doping type of a directly adjoining lowermost implantation region (111, 121) of a subsequent epitaxial layer.