Insulated gate bipolar transistor

摘要

An IGBT has layers between emitter and collector sides. The layers include a drift layer, a base layer electrically contacting an emitter electrode and separated from the drift layer, a first source region arranged on the base layer towards the emitter side and electrically contacting the emitter electrode, and a first trench gate electrode arranged lateral to the base layer and separated from the base layer, the first source region and the drift layer by a first insulating layer. A channel exits between the emitter electrode, the first source region, the base layer and the drift layer. A second insulating layer is arranged on top of the first trench gate electrode. An enhancement layer separates the base layer from the drift layer in a plane parallel to the emitter side. A grounded gate electrode includes a second, grounded trench gate electrode and an electrically conducting layer.

主权项

1. An insulated gate 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 lowly doped 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 the second conductivity type arranged between the drift layer and the emitter electrode, the base layer electrically contacting the emitter electrode and being completely separated from the drift layer; a first source region of the first conductivity type 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 first trench gate electrode arranged lateral to the base layer and extending deeper into the drift layer than the base layer, the first 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 second insulating layer arranged on the emitter side on top of the first trench gate electrode; an enhancement layer of the first conductivity type having a higher doping concentration than the drift layer and being arranged between the base layer and the drift layer, the enhancement layer separating the base layer from the drift layer at least in a plane parallel to the emitter side; a gate electrode including a second trench gate electrode and an electrically conducting layer, both of which are electrically connected to the emitter electrode; wherein the second trench gate electrode is arranged lateral to the base layer and extends deeper into the drift layer than the base layer, and the second trench gate electrode is separated from any surrounding layer or region by a third insulating layer, wherein the enhancement layer surrounds the base layer such that the base layer is separated from the drift layer and the third insulating layer, wherein the electrically conductive layer covers and laterally extends outside the second trench gate electrode at least to a region above the base layer, wherein the electrically conductive layer is separated from the base layer by a fourth electrically insulating layer, wherein the electrically conductive layer contacts the second trench gate electrode, and wherein the insulated gate bipolar transistor comprises: a fifth insulating layer arranged on the emitter side on top of the electrically conductive layer, the fifth insulating layer having a recess such that the electrically conducting layer electrically contacts the emitter electrode; and a second source region of the first conductivity type arranged at the emitter side on the base layer between the first trench gate electrode and the second trench gate electrode, the second source region having a higher doping concentration than the drift layer.