Patent ID: 9741795
Date: 2017-08-22
CPC Classifications: H01L

Claim:
1. An IGBT comprising at least one first type transistor cell, comprising: a base region, a first emitter region, a body region, and a second emitter region, wherein the body region is arranged between the first emitter region and the base region, and wherein the base region is arranged between the body region and the second emitter region; a gate electrode adjacent the body region, and dielectrically insulated from the body region by a gate dielectric; and a base electrode adjacent the base region, and dielectrically insulated from the base region by a base electrode dielectric, wherein the base region has a first base region section adjoining the base electrode dielectric and a second base region section arranged between the second emitter region and the first base region section, and wherein a doping concentration of the first base region section is higher than a doping concentration of the second base region section, wherein a ratio between the doping concentration of the first base region section and the doping concentration of the second base region section is at least 10, wherein the base electrode dielectric is thicker than the gate dielectric, wherein from the base region both the first base region section and the second base region section adjoin the body region.