US 12,224,313 B2
Semiconductor device and method for manufacturing the same
Yuhki Fujino, Kanazawa Ishikawa (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 15, 2023, as Appl. No. 18/197,600.
Application 18/197,600 is a continuation of application No. 17/198,334, filed on Mar. 11, 2021, granted, now 11,688,765.
Claims priority of application No. 2020-153233 (JP), filed on Sep. 11, 2020.
Prior Publication US 2023/0290820 A1, Sep. 14, 2023
Int. Cl. H01L 29/06 (2006.01); H01L 29/66 (2006.01); H01L 29/78 (2006.01)
CPC H01L 29/0653 (2013.01) [H01L 29/0623 (2013.01); H01L 29/0696 (2013.01); H01L 29/66712 (2013.01); H01L 29/7802 (2013.01); H01L 29/7813 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A method for manufacturing a semiconductor device, comprising:
forming a first diffusion region of a first conductivity type by doping an inner surface of an opening of a structural body with a first conductivity type impurity using plasma doping or solid phase diffusion, wherein:
the structural body includes:
a first semiconductor layer of the first conductivity type, and
a second semiconductor layer of the first conductivity type provided on the first semiconductor layer of the first conductivity type, an impurity concentration of the first conductivity type in the second semiconductor layer of the first conductivity type being lower than an impurity concentration of the first conductivity type in the first semiconductor layer of the first conductivity type, the opening being formed on an upper surface of the second semiconductor layer of the first conductivity type, and
the first diffusion region of the first conductivity type includes;
a first region separated from the inner surface of the opening of the structural body in a second direction perpendicular to a first direction, the first direction being from the first semiconductor layer of the first conductivity type to the second semiconductor layer of the first conductivity type, and
a second region positioned between the inner surface of the opening of the structural body and the first region, an impurity concentration of the first conductivity type in the second region being higher than an impurity concentration of the first conductivity type in the first region.