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 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. <EOS>