Patent ID: 8435863
Filing Date: 2013-05-07
Classification: H01L

Abstract:
1. A method for manufacturing a reverse-conducting semiconductor device, which includes a freewheeling diode and an insulated gate bipolar transistor on a common wafer of a first conductivity type, the insulated gate bipolar transistor including an emitter side and a collector side, the method comprising: providing a wafer with a first side and a second side opposite the first side, the first side of the wafer forming the emitter side of the insulated gate bipolar transistor, and the second side of the wafer forming the collector side of the insulated gate bipolar transistor; and manufacturing the reverse-conducting semiconductor device on the collector side of the insulated gate bipolar transistor, the manufacturing comprising: applying a shadow mask, which has at least one opening and which is not attached to the wafer, on the second side of the wafer; creating at least one third layer of a first or second conductivity type through the at least one opening of the shadow mask, after creation of the at least one third layer, creating at least one electrically conductive island, which is part of a second electrical contact in the finalized reverse-conducting semiconductor device, through the at least one opening of the shadow mask; removing the shadow mask; after removal of the shadow mask, forming at least one second layer of a different conductivity type than the conductivity type of the third layer on the second side of the wafer by using the at least one electrical conductive island as a mask for the creation of the at least one second layer, such that the at least one second and third layers are arranged alternately in the finalized reverse-conducting semiconductor device; and creating a second electrical contact, which is in direct electrical contact with the at least one second and third layers, on the second side of the wafer.