Semiconductor device

A semiconductor device comprising:

• a first semiconductor region of a first conductivity type;
• a second semiconductor region of a second conductivity type on the first semiconductor region;
• a third semiconductor region of the first conductivity type on the second semiconductor region;
• a first electrode surrounded by the first semiconductor region;
• a gate electrode above the first electrode;
• a gate insulating portion between the second semiconductor region and the gate electrode;
• a first insulating portion in contact with a first part of the first electrode and between the first part of the first electrode and the first semiconductor region;
• and
• a second insulating portion having a higher dielectric constant than the first insulating portion and the same dielectric constant as the gate insulating portion, in contact with a second part of the first electrode and between the second part of the first electrode and the first semiconductor region, the second part of the first electrode located closer to the gate electrode than the first part of the first electrode.