US 12,154,976 B2
Semiconductor device and method of manufacturing semiconductor device
Kazuya Konishi, Tokyo (JP); Shinya Soneda, Tokyo (JP); Tetsuya Nitta, Tokyo (JP); and Akihiko Furukawa, Tokyo (JP)
Assigned to Mitsubishi Electric Corporation, Tokyo (JP)
Filed by Mitsubishi Electric Corporation, Tokyo (JP)
Filed on Oct. 1, 2021, as Appl. No. 17/491,686.
Claims priority of application No. 2020-206617 (JP), filed on Dec. 14, 2020.
Prior Publication US 2022/0190146 A1, Jun. 16, 2022
Int. Cl. H01L 29/739 (2006.01); H01L 29/861 (2006.01)
CPC H01L 29/7397 (2013.01) [H01L 29/861 (2013.01)] 24 Claims
OG exemplary drawing
 
1. A semiconductor device, comprising:
a semiconductor substrate on which an emitter electrode and a gate electrode are provided;
a base layer of a first conductivity type which is provided on an upper surface side of the semiconductor substrate;
a source layer of a second conductivity type which is provided on the upper surface side of the base layer;
an active portion which is provided on an insulating film which is an inner surface of a first trench penetrating the base layer and the source layer, the active portion being connected to the gate electrode;
a first trench contact portion and a second trench contact portion provided to face a first side portion and a second side portion of the first trench, respectively, in a plan view, the emitter electrode being provided inside each of the first trench contact portion and the second trench contact portion;
a first contact layer of the first conductivity type which is connected to a lower portion of the first trench contact portion and has an impurity concentration of the first conductivity type which is higher than that of the base layer;
a second contact layer of the first conductivity type which is connected to a lower portion of the second trench contact portion and has an impurity concentration of the first conductivity type which is higher than that of the base layer; and
a collector electrode provided on a lower surface of the semiconductor substrate,
wherein the distance between the first side portion and the first trench contact portion is larger than that between the second side portion and the second trench contact portion in a plan view,
the first contact layer is separated from the first side portion and the second contact layer is connected to the second side portion in a cross section, and
an outline of the first trench in the first side portion has at least one of one or more concave shapes and convex shapes in a plan view.