Semiconductor device and method of manufacturing semiconductor device

A semiconductor device comprising:

• a semiconductor substrate of a first conductivity type;
• a first semiconductor layer of the first conductivity type, provided on a front surface of the semiconductor substrate;
• a second semiconductor layer of a second conductivity type, provided on a first side of the first semiconductor layer, opposite a second side of the first semiconductor layer toward the semiconductor substrate;
• a first semiconductor region of the first conductivity type, selectively provided in the second semiconductor layer, the first semiconductor region having an impurity concentration that is higher than that of the semiconductor substrate;
• a trench penetrating the first semiconductor region and the second semiconductor layer, and reaching the first semiconductor layer;
• a gate electrode provided in the trench, via a gate insulating film;
• a first electrode in contact with the first semiconductor region and the second semiconductor layer;
• a second electrode provided on a rear surface of the semiconductor substrate;
• and
• a second semiconductor region of the second conductivity type, selectively provided in the first semiconductor layer, the second semiconductor region contacting a bottom of the trench and having an impurity concentration that is higher than that of the second semiconductor layer, wherein
• the second semiconductor region is implanted with an impurity and a first element at a predetermined ratio, the impurity determining a conductivity type of the second semiconductor region and displacing a second element, the first element bonding with the displaced second element.