A reverse-conducting power semiconductor device with a wafer has first and second main sides which are arranged opposite and parallel to each other. The device includes a plurality of diode cells and a plurality of gate commutated thyristors (GCT) cells. Each GCT cell includes layers of a first conductivity type (e.g., n-type) and a second conductivity type (e.g., p-type) between the first and second main sides. The device includes at least one mixed part in which diode anode layers of the diode cells alternate with first cathode layers of the GCT cells. In each diode cell, a diode buffer layer of the first conductivity type is arranged between the diode anode layer and a drift layer such that the diode buffer layer covers lateral sides of the diode anode layer from the first main side to a depth of approximately 90% of the thickness of the diode anode layer.