Patent ID: 11955546
Assignee: TOSHIBA ELECTRONIC DEVICES & STORAGE CORPORATION
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 10:
11. A semiconductor device, comprising:
a semiconductor part;
a first electrode provided at a backside of the semiconductor part;
a second electrode provided at a front side of the semiconductor part;
a first control electrode provided between the semiconductor part and the second electrode, the first control electrode being provided inside the semiconductor part and electrically insulated from the semiconductor part by a first insulating portion, the first control electrode being electrically insulated from the second electrode by a first inter-layer insulating film;
a second control electrode provided between the first control electrode and the first electrode, the second control electrode being provided inside the semiconductor part and electrically insulated from the semiconductor part by a second insulating portion; and
a third control electrode provided between the second control electrode and the first electrode, the third control electrode being provided inside the semiconductor part and electrically insulated from the semiconductor part by a third insulating portion,
the first to third control electrodes being arranged in a first direction from the second electrode toward the first electrode,
the third control electrode being electrically insulated from the second control electrode by a fourth insulating portion provided between the second control electrode and the third control electrode,
the second control electrode being electrically insulated from the first control electrode by a fifth insulating portion provided between the first control electrode and the second control electrode,
the semiconductor part including a first layer of a first conductivity type, a second layer of a second conductivity type, a third layer of the first conductivity type, and a fourth layer of the second conductivity type,
the first layer extending between the first electrode and the second electrode, the second control electrode facing the first layer via the second insulating portion, the third control electrode being provided inside the first layer,
the second layer being provided between the first layer and the second electrode, the second layer facing the first control electrode via the first insulating portion,
the third layer being selectively provided between the second layer and the second electrode, the third layer contacting the first insulating portion and being electrically connected to the second electrode,
the fourth layer being provided between the first layer and the first electrode and electrically connected to the first electrode, wherein
the semiconductor part further includes a sixth layer of the first conductivity type, the sixth layer being provided between the first layer and the second layer, the sixth layer including a first conductivity type impurity with a higher concentration than a concentration of a first conductivity type impurity in the first layer, and
the first control electrode faces the sixth layer via the first insulating portion.