Semiconductor device

A semiconductor device comprising:

• a drift region of a first conductivity type which is provided in a semiconductor substrate;
• a plurality of trench portions which extend in a predetermined trench extending direction at a front surface of the semiconductor substrate;
• a base region of a second conductivity type which is provided above the drift region;
• an emitter region of the first conductivity type which is provided above the drift region and has a doping concentration higher than that of the drift region;
• a contact region of the second conductivity type which is provided above the drift region and has a doping concentration higher than that of the base region;
• an interlayer dielectric film which is provided above the semiconductor substrate and has a contact hole;
• and
• an emitter electrode which is provided above the semiconductor substrate and is in contact with the semiconductor substrate via the contact hole, wherein
• the plurality of trench portions include a gate trench portion including a gate conductive portion and a gate dielectric film,
• the emitter region includes
• a first emitter portion which is in contact with the front surface of the semiconductor substrate,
• a second emitter portion which is provided below the first emitter portion and has a doping concentration lower than that of the first emitter portion, and
• a third emitter portion which is provided below the second emitter portion and has a doping concentration higher than that of the second emitter portion, and
• the gate trench portion includes
• a dummy conductive portion at an emitter potential, which is provided above the gate conductive portion, in a trench.