Semiconductor device and method for controlling semiconductor device

A semiconductor device, comprising:

• a first electrode;
• a second electrode separated from the first electrode in a first direction;
• a first semiconductor region located between the first electrode and the second electrode in the first direction, the first semiconductor region being of a first conductivity type;
• a second semiconductor region located between the first semiconductor region and the second electrode, the second semiconductor region being of a second conductivity type;
• a third semiconductor region located between the first semiconductor region and the first electrode, the third semiconductor region being of the second conductivity type and being electrically connected with the first electrode;
• a first gate electrode facing the second semiconductor region via a first insulating film in a second direction, the first gate electrode facing the second electrode via a third insulating film contacting the first insulating film, the second direction crossing the first direction, a plurality of the first gate electrodes being provided;
• a second gate electrode facing the second semiconductor region via a second insulating film in the second direction, the second gate electrode facing the second electrode via the third insulating film contacting the second insulating film, a different voltage from the first gate electrode being applied to the second gate electrode, a plurality of the second gate electrodes being provided;
• a fourth semiconductor region located between the second semiconductor region and the second electrode, the fourth semiconductor region being of the first conductivity type and being next to the first gate electrode with the first or third insulating film interposed;
• and
• a fifth semiconductor region located between the second semiconductor region and the second electrode, the fifth semiconductor region being of the second conductivity type, being next to the second gate electrode with the second or third insulating film interposed, and including a boundary portion that electrically contacts the second electrode,
• a distance between an upper surface of the fourth semiconductor region and the first electrode being greater than a distance between the boundary portion and the first electrode.