Abstract:
An IGBT has layers between emitter and collector sides. The layers include a collector layer on the collector side, a drift layer, a base layer of a second conductivity type, a first source region arranged on the base layer towards the emitter side, a trench gate electrode arranged lateral to the base layer and extending deeper into the drift layer than the base layer, a well arranged lateral to the base layer and extending deeper into the drift layer than the base layer, an enhancement layer surrounding the base layer so as to completely separate the base layer from the drift layer and the well, an electrically conducting layer covering the well and separated from the well by a second electrically insulating layer, and a third insulating layer having a recess on top of the electrically conducting layer such that the electrically conducting layer electrically contacts a emitter electrode.
Abstract:
An IGBT has layers between emitter and collector sides, including a drift layer, a base layer electrically contacting an emitter electrode and completely separated from the drift layer, first and second source regions arranged on the base layer towards the emitter side and electrically contacting the emitter electrode, and first and second trench gate electrodes. The first trench gate electrodes are separated from the base layer, the first source region and the drift layer by a first insulating layer. A channel is formable 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 electrodes. An enhancement layer separates the base layer from the drift layer. The second trench gate electrode is separated from the base layer, the enhancement layer and the drift layer by a third insulating layer.
Abstract:
A method for manufacturing a bipolar punch-through semiconductor device is disclosed, which includes providing a wafer having a first and a second side, wherein on the first side a high-doped layer of the first conductivity type having constant high doping concentration is arranged; epitaxially growing a low-doped layer of the first conductivity type on the first side; performing a diffusion step by which a diffused inter-space region is created at the inter-space of the layers; creating at least one layer of the second conductivity type on the first side; and reducing the wafer thickness within the high-doped layer on the second side so that a buffer layer is created, which can include the inter-space region and the remaining part of the high-doped layer, wherein the doping profile of the buffer layer decreases steadily from the doping concentration of the high-doped region to the doping concentration of the drift layer.