Semiconductor device and method for manufacturing same

A semiconductor device, comprising:

• a first semiconductor region of a first conductivity type;
• a second semiconductor region of a second conductivity type provided on a major surface of the first semiconductor region;
• a third semiconductor region of the first conductivity type provided on the second semiconductor region;
• an insulating region penetrating the third semiconductor region and the second semiconductor region to reach the first semiconductor region;
• a first main electrode contacting the third semiconductor region and an upper surface of the insulating region;
• a first internal electrode part disposed in a center portion of the insulating region and in electrical contact with the first main electrode, the first internal electrode part extending within the insulating region from a portion adjacent to the third semiconductor region to a portion adjacent to the first semiconductor region;
• a second internal electrode part in electrical contact with the first main electrode and provided as two or more pieces with at least one piece provided on each side of the first internal electrode in the insulating region between the first internal electrode part and the first semiconductor region;
• a control electrode provided in the insulating region in a portion above the second internal electrode and adjacent to the first semiconductor region, the second semiconductor region, and the third semiconductor region, the control electrode extending within the insulating region from the portion adjacent to
• the third semiconductor region to reach the portion adjacent to the first semiconductor region.