US 12,439,676 B2
Semiconductor device
Takuo Kikuchi, Kamakura (JP); and Tatsuya Nishiwaki, Yokohama (JP)
Assigned to KABUSHIKI KAISHA TOSHIBA, Tokyo (JP); and TOSHIBA ELECTRONIC DEVICES & STORAGE CORPORATION, Tokyo (JP)
Filed by KABUSHIKI KAISHA TOSHIBA, Tokyo (JP); and TOSHIBA ELECTRONIC DEVICES & STORAGE CORPORATION, Tokyo (JP)
Filed on May 25, 2022, as Appl. No. 17/664,989.
Claims priority of application No. 2021-153547 (JP), filed on Sep. 21, 2021.
Prior Publication US 2023/0090527 A1, Mar. 23, 2023
Int. Cl. H10D 64/27 (2025.01); H01L 21/3105 (2006.01); H10D 62/10 (2025.01)
CPC H10D 64/514 (2025.01) [H01L 21/31053 (2013.01); H10D 62/103 (2025.01); H10D 64/513 (2025.01)] 21 Claims
OG exemplary drawing
 
1. A semiconductor device, comprising:
a semiconductor part including a first semiconductor layer and a second semiconductor layer, the first semiconductor layer being of a first conductivity type, the second semiconductor layer being of a second conductivity type;
a first electrode provided on a back surface of the semiconductor part;
a second electrode provided at a front side of the semiconductor part, the first semiconductor layer extending between the first electrode and the second electrode, the second semiconductor layer being provided between the first semiconductor layer and the second electrode, the second semiconductor layer being electrically connected to the second electrode;
a plurality of third electrodes extending into the first semiconductor layer from the front side of the semiconductor part through the second semiconductor layer, the third electrodes being apart from each other in a direction along the back surface of the semiconductor part, the third electrodes being electrically connected to the second electrode;
a fourth electrode extending into the first semiconductor layer from the front side of the semiconductor part, the fourth electrode surrounding the plurality of third electrodes in a plane parallel to the back surface, the fourth electrode being electrically connected to the second electrode;
a first insulating film provided between the semiconductor part and the third electrode, the first insulating film electrically insulating each of the third electrodes from the semiconductor part; and
a second insulating film provided between the semiconductor part and the fourth electrode, the second insulating film electrically insulating the fourth electrode from the semiconductor part, the second insulating film having a second film thickness greater than a first film thickness of the first insulating film,
wherein the first insulating film physically contacts the first semiconductor layer and the third electrode, and
the second insulating film physically contacts the first semiconductor layer and the fourth electrode.