Semiconductor device

A semiconductor device comprising:

• a first semiconductor region comprising:
• a first semiconductor region of a first conductivity type;
• a second semiconductor region of a second conductivity type that is arranged above the first semiconductor region;
• a third semiconductor region of the first conductivity type that is arranged above the second semiconductor region;
• a first trench penetrating the second semiconductor region in a depth direction;
• a first inner trench electrode that is arranged in the first trench through a first insulating film;
• a fourth semiconductor region of the second conductivity type that is arranged under the first semiconductor region and on an opposite side of the second semiconductor region;
• an upper electrode electrically connected to the third semiconductor region;
• and
• a lower electrode electrically connected to the fourth semiconductor region;
• a second semiconductor region comprising:
• a fifth semiconductor region of the second conductivity type that is electrically connected to the upper electrode and arranged above the first semiconductor region;
• a sixth semiconductor region of the first conductivity type that is arranged under the first semiconductor region, and is electrically connected to the lower electrode, and is arranged on the opposite side of the fifth semiconductor region;
• a second trench penetrating the fifth semiconductor region in the depth direction;
• and
• a second inner trench electrode that is arranged in the second trench through a second insulating film;
• and
• a dummy region comprising:
• a seventh semiconductor region of the second conductivity type that is arranged on the first semiconductor region between the first semiconductor region and the second semiconductor region;
• a third trench penetrating the seventh semiconductor region in the depth direction;
• and
• a third inner trench electrode electrically connected to the first inner trench electrode through a third insulating film in the third trench.