	US 12,408,397 B2
	Semiconductor device
Hiroshi Kono, Himeji Hyogo (JP); and Katsuhisa Tanaka, Himeji Hyogo (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 Sep. 9, 2022, as Appl. No. 17/941,725.
Claims priority of application No. 2022-049040 (JP), filed on Mar. 24, 2022.
Prior Publication US 2023/0307496 A1, Sep. 28, 2023
Int. Cl. H10D 62/13 (2025.01); H10D 30/66 (2025.01); H10D 62/832 (2025.01)

CPC H10D 62/153 (2025.01) [H10D 30/668 (2025.01); H10D 62/8325 (2025.01)]

10 Claims

1. A semiconductor device comprising:

a silicon carbide layer having a first face parallel to a first direction and a second direction orthogonal to the first direction, and a second face facing the first face;

a first trench provided on a side of the first face in the silicon carbide layer and extending in the first direction;

a second trench provided on the side of the first face in the silicon carbide layer, provided in the second direction with respect to the first trench, and extending in the first direction;

a first gate electrode provided in the first trench;

a second gate electrode provided in the second trench;

a first gate insulating layer provided between the first gate electrode and the silicon carbide layer;

a second gate insulating layer provided between the second gate electrode and the silicon carbide layer;

a first silicon carbide region of a first conductive type provided in the silicon carbide layer and extending in the second direction;

a second silicon carbide region of a second conductive type provided in the silicon carbide layer, extending in the second direction, and disposed in the first direction with respect to the first silicon carbide region;

a third silicon carbide region of a first conductive type provided in the silicon carbide layer, extending in the second direction, and disposed in the first direction with respect to the second silicon carbide region;

a fourth silicon carbide region of a second conductive type provided in the silicon carbide layer, extending in the second direction, and disposed in the first direction with respect to the third silicon carbide region;

a fifth silicon carbide region of a first conductive type provided in the silicon carbide layer, extending in the second direction, disposed between the first silicon carbide region and the first face, disposed in a third direction perpendicular to the first face with respect to the first silicon carbide region, disposed between the first trench and the second face and between the second trench and the second face, and having a first-conductivity type impurity concentration higher than a first-conductivity type impurity concentration in the first silicon carbide region, and;

a sixth silicon carbide region of a second conductive type provided in the silicon carbide layer, extending in the second direction, disposed between the second silicon carbide region and the first face, disposed in the third direction with respect to the second silicon carbide region, disposed between the first trench and the second face and between the second trench and the second face, and having a second-conductivity type impurity concentration higher than a second-conductivity type impurity concentration in the second silicon carbide region;

a seventh silicon carbide region of a first conductive type provided in the silicon carbide layer, extending in the second direction, disposed between the third silicon carbide region and the first face, disposed in the third direction with respect to the third silicon carbide region, disposed between the first trench and the second face and between the second trench and the second face, having a first-conductivity type impurity concentration higher than a first-conductivity type impurity concentration in the third silicon carbide region;

an eighth silicon carbide region of a second conductive type provided in the silicon carbide layer, extending in the second direction, disposed between the fourth silicon carbide region and the first face, disposed in the third direction with respect to the fourth silicon carbide region, disposed between the first trench and the second face and between the second trench and the second face, and having a second-conductivity type impurity concentration higher than a second-conductivity type impurity concentration in the fourth silicon carbide region;

a ninth silicon carbide region of a first conductive type provided in the silicon carbide layer, disposed between the fifth silicon carbide region and the first face, disposed between the sixth silicon carbide region and the first face, disposed between the seventh silicon carbide region and the first face, disposed between the eighth silicon carbide region and the first face, and disposed between the first trench and the second trench;

a tenth silicon carbide region of a second conductive type provided in the silicon carbide layer, disposed between the ninth silicon carbide region and the first face, and disposed between the first trench and the second trench;

an eleventh silicon carbide region of a first conductive type provided in the silicon carbide layer, disposed between the ninth silicon carbide region and the first face, disposed between the first trench and the second trench, and having a first-conductivity type impurity concentration higher than a first-conductivity type impurity concentration in the ninth silicon carbide region;

a first electrode provided on the side of the first face with respect to the silicon carbide layer and in contact with the tenth silicon carbide region and the eleventh silicon carbide region; and

a second electrode provided on a side of the second face with respect to the silicon carbide layer.