US 12,256,560 B1
IGBT with electric field relaxation doping profile
Yosuke Sakurai, Azumino (JP); and Yuichi Onozawa, Matsumoto (JP)
Assigned to FUJI ELECTRIC CO., LTD., Kanagawa (JP)
Filed by FUJI ELECTRIC CO., LTD., Kanagawa (JP)
Filed on Mar. 12, 2024, as Appl. No. 18/603,082.
Application 18/603,082 is a continuation of application No. 17/409,819, filed on Aug. 24, 2021, granted, now 11,942,535.
Application 17/409,819 is a continuation of application No. PCT/JP2020/032871, filed on Aug. 31, 2020.
Claims priority of application No. 2019-167090 (JP), filed on Sep. 13, 2019.
Int. Cl. H01L 29/739 (2006.01); H01L 29/06 (2006.01); H10D 12/00 (2025.01); H10D 62/10 (2025.01)
CPC H10D 12/461 (2025.01) [H10D 62/102 (2025.01); H10D 62/127 (2025.01)] 18 Claims
OG exemplary drawing
 
1. A semiconductor device, comprising:
a drift region that is of a first conductivity type and is provided in a semiconductor substrate;
a base region that is of a second conductivity type and is provided above the drift region; and
an accumulation region that is of the first conductivity type, is provided between the base region and the drift region, and has a higher doping concentration than the drift region,
wherein
the semiconductor device has a doping concentration distribution in a depth direction of the semiconductor device in which a film thickness of an electric field relaxation region that is of the first conductivity type is greater than or equal to 0.4 μm and less than or equal to 3.0 μm, the electric field relaxation region being a region from a location of a PN junction at a lower end of the base region to a location of a half-value of a peak of the accumulation region on the base region side.