Semiconductor device including auxiliary electrode that is electrically connected to a control electrode via a second electrode layer

A semiconductor device comprising:

• a semiconductor layer having a first principal surface and a second principal surface on an opposite side of the first principal surface;
• a first region of a first conductivity type formed in a surface layer portion of the first principal surface of the semiconductor layer;
• a cell structure having a second region of a second conductivity type formed in a surface layer portion of the first region, a third region of the first conductivity type formed in the surface layer portion of the first region such that the third region is in contact with the second region, and a control electrode opposing the second region via a first insulating film adjacent to the second region, the control electrode forming a current path in the second region;
• a first electrode layer formed on the first principal surface of the semiconductor layer such that the first electrode layer covers the cell structure, and electrically connected to the third region;
• a second electrode layer formed on the first principal surface of the semiconductor layer separately from the first electrode layer, and electrically connected to the control electrode;
• a first recess portion formed in the surface layer portion of the first principal surface of the semiconductor layer such that the first recess portion faces the second electrode layer;
• a second insulating film covering the first recess portion;
• and
• an auxiliary electrode embedded in the first recess portion via the second insulating film, and electrically connected to the second electrode layer, wherein
• the auxiliary electrode includes a first portion embedded in the first recess portion, and a second portion formed such that the second portion is integrated with the first portion and formed on the first principal surface of the semiconductor layer,
• when viewed in a direction perpendicular to a thickness direction of the semiconductor layer, the second electrode layer has one end and another end, and the second portion of the auxiliary electrode has one end and another end, and
• the one end and the other end of the second electrode layer are disposed between the one end and the other end of the second portion of the auxiliary electrode.