Patent ID: 11894426
Assignee: FUJI ELECTRIC CO., LTD.
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 11:
12. A semiconductor device comprising:
a semiconductor substrate including a bulk donor;
a first buffer region of a first conductivity type, the first buffer region being provided on a lower surface side of the semiconductor substrate and having one or more doping concentration peaks and one or more hydrogen concentration peaks in a depth direction of the semiconductor substrate;
a transistor portion; and
a diode portion, wherein
a doping concentration at a shallowest concentration peak, out of the doping concentration peaks of the first buffer region, closest to the lower surface of the semiconductor substrate is 50 times as high as a bulk donor concentration of the semiconductor substrate or lower,
the diode portion includes:
the first buffer region; and
a cathode region of the first conductivity type provided between the first buffer region and the lower surface of the semiconductor substrate,

the transistor portion includes:
a second buffer region of the first conductivity type, the second buffer region being provided on the lower surface side of the semiconductor substrate and having one or more doping concentration peaks and one or more hydrogen concentration peaks in the depth direction of the semiconductor substrate; and
a collector region of a second conductivity type provided between the second buffer region and the lower surface of the semiconductor substrate, and

doping concentrations at each of the doping concentration peaks in the second buffer region are the same as doping concentrations at the doping concentration peaks provided at the same depth positions in the first buffer region.