An IGBT includes a semiconductor portion with IGBT cells. Each IGBT cell includes a source zone of a first conductivity type, a body zone of a second, complementary conductivity type, and a drift zone of the first conductivity type separated from the source zone by the body zone. An emitter electrode includes a main layer and an interface layer. The interface layer directly adjoins at least one of the body zone and a supplementary zone of the second conductivity type. A contact resistance between the semiconductor portion and the interface layer is higher than between the semiconductor portion and a material of the main layer. For example, the interface layer may reduce diode emitter efficiency and reverse recovery losses in IGBTs.