Patent ID: 9105680
Filing Date: 2015-08-11
Classification: H01L

Abstract:
1. An insulated gated bipolar transistor having layers between an emitter electrode on an emitter side and a collector electrode on a collector side opposite to the emitter side, the insulated gate bipolar transistor comprising: a drift layer of a first conductivity type; a collector layer of a second conductivity type different than the first conductivity type, the collector layer being arranged between the drift layer and the collector electrode and electrically contacting the collector electrode; a base layer of a second conductivity type, the base layer being arranged between the drift layer and the emitter electrode, the base layer electrically contacting the emitter electrode; a first source region of the first conductivity type, the first source region being arranged on the base layer towards the emitter side and electrically contacting the emitter electrode, the first source region having a higher doping concentration than the drift layer; a trench gate electrode arranged lateral to the base layer and extending deeper into the drift layer than the base layer, the trench gate electrode being separated from the base layer, the first source region and the drift layer by a first insulating layer, wherein a channel is formable between the emitter electrode, the first source region, the base layer and the drift layer; a well of the second conductivity type, which is arranged lateral to the base layer and extends deeper into the drift layer than the base layer; an enhancement layer of the first conductivity type, which surrounds the base layer such that the enhancement layer completely separates the base layer from the drift layer and the well; in addition to the emitter electrode, an electrically conducting layer, which covers the well, wherein the electrically conductive layer is separated from the well by a second electrically insulating layer; and a third insulating layer, which is arranged on the emitter side on top of the trench gate electrode, the electrically conductive layer and those parts of the base layer, the enhancement layer and the drift layer lying between the trench gate electrode and the well, the third insulating layer having a recess on top of the electrically conducting layer such that the electrically conducting layer electrically contacts the emitter electrode.