Patent ID: 11955540
Assignee: FUJI ELECTRIC CO., LTD.
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 18:
19. A production method of a semiconductor device including a semiconductor substrate having a first conductive type drift region, comprising:
forming a second conductive type base region provided between the drift region and an upper surface of the semiconductor substrate, and a second conductive type contact region with a higher doping concentration than the base region, which is provided between the base region and the upper surface of the semiconductor substrate;
forming a contact trench penetrating the contact region on the upper surface of the semiconductor substrate;
forming a second conductive type high-concentration plug region with a higher doping concentration than the contact region, which in contact with a bottom portion of the contact trench, wherein the upper surface of the high-concentration plug region is deeper into the semiconductor substrate than the contact region; and
providing a conductive material in an interior of the contact trench and forming a trench contact.