Patent ID: 8450777

Claim:
A reverse-conducting insulated gate bipolar transistor comprising: a first layer of a first conductivity type with a first main side and a second main side opposite the first main side; a second layer of a second conductivity type arranged on the first main side; at least one third layer of the first conductivity type arranged on the first main side and surrounded by the second layer; a first electrically insulating layer arranged on the first main side and partially covering the at least one third layer; an electrically conductive fourth layer arranged on the first main side and being electrically insulated from the at least one third layer, the second layer and the first layer by the first electrically insulating layer; a second electrically insulating layer covering the first insulating layer, wherein the first and second electrically insulating layers form a fifth layer, the electrically conductive fourth layer being arranged between the first and second electrically insulating layers such that the fourth layer is embedded in the fifth layer, the at least one third layer, the fourth layer and the fifth layer being formed in such a way that a first opening is surrounded by the at least one third layer, the fourth layer, and the fifth layer and arranged above the second layer; a first electrical contact arranged on the first main side in direct electrical contact with the second layer and the third layer within the first opening; at least one sixth layer of the second conductivity type and at least one seventh layer of the first conductivity type, which are arranged on the second main side, the at least one sixth and seventh layers being arranged alternately in a plane; a second electrical contact arranged on the second main side in direct electrical contact with the at least one sixth layer and the at least one seventh layer; and at least one ninth layer constituting a defect layer with defect centers, the defect centers not contributing to doping, wherein the ninth layer is arranged self-aligned to the first opening, so that a lateral extension of the at least one ninth layer being limited to an area defined by a border of the first opening within at least one of the second layer and the first layer below the second layer.