Reverse-conducting semiconductor device, which comprises a freewheeling diode and an insulated gate bipolar transistor on a common wafer, part of which wafer forms a base layer of a first conductivity type with a first doping concentration and a base layer thickness, wherein the insulated gate bipolar transistor comprises a collector side and an emitter side opposite to the collector side of the wafer, wherein the base layer thickness is the maximum vertical distance between the collector and emitter side (103, 104) of that part of the wafer with the first doping concentration, a first layer of the first conductivity type and higher doping concentration than the first doping concentration and a second layer of a second conductivity type are alternately arranged on the collector side, wherein a third layer of the first conductivity type, a fourth layer of the second conductivity type and an electrically conductive fifth layer in form of a gate electrode are arranged on the emitter side, wherein the third layer is surrounded by the fourth layer and wherein the electrically conductive fifth layer is electrically insulated from the at least one fourth layer, the third layer and the base layer by an insulating layer, wherein the first layer comprises at least one first region, wherein each first region has a first region width, wherein the second layer comprises at least one second region, wherein each second region has a second region width, and at least one third region, wherein each third region has a third region width, wherein any region has a region width and a region area, which is surrounded by a region border, wherein a shortest distance is the minimum length between a point within said region area and a point on said region border, wherein each region width is defined as two times the maximum value of any shortest distance within said region, wherein the reverse-conducting semiconductor device comprises an electrically active region, which active region is an area within the wafer, which includes and is arranged below the third layer, fourth layer and fifth layer, wherein each third region area is an area, which border is defined by any two surrounding first regions, wherein a distance between any two surrounding first regions measured across each third region is bigger than two times the base layer thickness, wherein the at least one second region is that part of the second layer, which is not the at least one third region, wherein the at least one third region is arranged in a central part of the active region in such a way that there is a minimum distance between each third region border to the active region border of at least once the base layer thickness, wherein the sum of the areas of the at least one third region is between 10 % and 30 % of the active region, wherein each first region width is smaller than the base layer thickness, wherein the at least one third region has a star shape with either - three protrusions forming a tri-star, - four protrusions forming a cross, wherein the first layer does not comprise a region having a region width, which is equal to or larger than two times the base layer thickness, or - five or more protrusions. - three protrusions forming a tri-star, - four protrusions forming a cross, wherein the first layer does not comprise a region having a region width, which is equal to or larger than two times the base layer thickness, or - five or more protrusions.