Patents by Inventor Yuki OHUCHI

Yuki OHUCHI has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 12294019
    Abstract: A method for manufacturing a nitride semiconductor device including: forming N-type regions in a nitride semiconductor layer; implanting ions of an acceptor element into a region sandwiched by the N-type regions in the nitride semiconductor layer; and forming a P-type region sandwiched by the N-type regions by subjecting the nitride semiconductor layer to heat treatment and activating the acceptor element. The forming the N-type regions includes implanting ions of a donor element to the nitride semiconductor layer such that concentration of the donor element in the N-type regions is equal to or greater than concentration of the acceptor element in the P-type region. The implanting ions of the acceptor element includes implanting ions of the acceptor element such that concentration of the acceptor element in the P-type region is 1×1019 cm?3 or more and 1×1021 cm?3 or less.
    Type: Grant
    Filed: January 24, 2022
    Date of Patent: May 6, 2025
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Ryo Tanaka, Yuki Ohuchi, Katsunori Ueno, Shinya Takashima
  • Patent number: 12237379
    Abstract: A method for manufacturing a nitride semiconductor device including: forming an N-type region in a nitride semiconductor layer; implanting ions of an acceptor element into a region under the N-type region in the nitride semiconductor layer; and forming a first P-type region under the N-type region by subjecting the nitride semiconductor layer to heat treatment and activating the acceptor element. The forming the N-type region includes implanting ions of a donor element into the nitride semiconductor layer such that concentration of the donor element in the N-type region is equal to or greater than concentration of the acceptor element in the first P-type region. The implanting ions of the acceptor element into a region under the N-type region includes implanting ions of the acceptor element such that concentration of the acceptor element in the first P-type region is 1×1019 cm?3 or more and 1×1021 cm?3 or less.
    Type: Grant
    Filed: January 25, 2022
    Date of Patent: February 25, 2025
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Ryo Tanaka, Yuki Ohuchi, Katsunori Ueno, Shinya Takashima
  • Publication number: 20240387641
    Abstract: Provided is a nitride semiconductor device including a p-type region having a high concentration, and a method of manufacturing the same. The nitride semiconductor device includes a nitride crystal layer, and a p-type region provided in the nitride crystal layer. The p-type region includes Mg at a concentration in a range of 3×1018 cm?3 or greater and 1×1021 cm?3 or less, and at least either a group-13 element or an acceptor element at a concentration in a range of 3×1017 cm?3 or greater and 5×1021 cm?3 or less.
    Type: Application
    Filed: March 15, 2024
    Publication date: November 21, 2024
    Applicant: FUJI ELECTRIC CO., LTD.
    Inventors: Yuki OHUCHI, Katsunori UENO, Ryo TANAKA, Shinya TAKASHIMA
  • Patent number: 11837656
    Abstract: To provide a nitride semiconductor device excellent in switching characteristics. A nitride semiconductor device includes: a gallium nitride layer having a first principal surface and a second principal surface located on an opposite side to the first principal surface and having a trench formed from the first principal surface to the second principal surface side; and a field effect transistor formed in the gallium nitride layer, wherein the trench has a first side surface and a second side surface inside the trench, the first side surface is a nitrogen face in the surface layer of which nitrogen atoms are located, the second side surface is a gallium face in the surface layer of which gallium atoms are located, and the field effect transistor has: a gate insulating film formed on the first side surface; and a gate electrode formed in the trench and covering the gate insulating film.
    Type: Grant
    Filed: September 22, 2021
    Date of Patent: December 5, 2023
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Katsunori Ueno, Yuki Ohuchi
  • Patent number: 11830915
    Abstract: A nitride semiconductor device includes a GaN-based semiconductor layer; and an insulating film provided on a first surface of the GaN-based semiconductor layer, the insulating film containing O atoms, and other constituent atoms other than O. An interface between the GaN-based semiconductor layer and the insulating film has a terminating species which terminates a dangling bond of a Ga atom, the terminating species has an outermost electron shell in which one electron is deficient from an allowed number of outermost electrons, and is an atom or molecule having stronger bond to the Ga atom than a H atom, an amount of Ga—O bonds is greater than an amount of bonds between the Ga atoms and the other constituent atoms.
    Type: Grant
    Filed: February 26, 2021
    Date of Patent: November 28, 2023
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Yuki Ohuchi, Katsunori Ueno
  • Publication number: 20220285503
    Abstract: A method for manufacturing a nitride semiconductor device including: forming N-type regions in a nitride semiconductor layer; implanting ions of an acceptor element into a region sandwiched by the N-type regions in the nitride semiconductor layer; and forming a P-type region sandwiched by the N-type regions by subjecting the nitride semiconductor layer to heat treatment and activating the acceptor element. The forming the N-type regions includes implanting ions of a donor element to the nitride semiconductor layer such that concentration of the donor element in the N-type regions is equal to or greater than concentration of the acceptor element in the P-type region. The implanting ions of the acceptor element includes implanting ions of the acceptor element such that concentration of the acceptor element in the P-type region is 1×1019 cm?3 or more and 1×1021 cm?3 or less.
    Type: Application
    Filed: January 24, 2022
    Publication date: September 8, 2022
    Applicant: FUJI ELECTRIC CO., LTD.
    Inventors: Ryo TANAKA, Yuki OHUCHI, Katsunori UENO, Shinya TAKASHIMA
  • Publication number: 20220285504
    Abstract: A method for manufacturing a nitride semiconductor device including: forming an N-type region in a nitride semiconductor layer; implanting ions of an acceptor element into a region under the N-type region in the nitride semiconductor layer; and forming a first P-type region under the N-type region by subjecting the nitride semiconductor layer to heat treatment and activating the acceptor element. The forming the N-type region includes implanting ions of a donor element into the nitride semiconductor layer such that concentration of the donor element in the N-type region is equal to or greater than concentration of the acceptor element in the first P-type region. The implanting ions of the acceptor element into a region under the N-type region includes implanting ions of the acceptor element such that concentration of the acceptor element in the first P-type region is 1×1019 cm?3 or more and 1×1021 cm?3 or less.
    Type: Application
    Filed: January 25, 2022
    Publication date: September 8, 2022
    Applicant: FUJI ELECTRIC CO., LTD.
    Inventors: Ryo TANAKA, Yuki OHUCHI, Katsunori UENO, Shinya TAKASHIMA
  • Publication number: 20220140134
    Abstract: To provide a nitride semiconductor device excellent in switching characteristics. A nitride semiconductor device includes: a gallium nitride layer having a first principal surface and a second principal surface located on an opposite side to the first principal surface and having a trench formed from the first principal surface to the second principal surface side; and a field effect transistor formed in the gallium nitride layer, wherein the trench has a first side surface and a second side surface inside the trench, the first side surface is a nitrogen face in the surface layer of which nitrogen atoms are located, the second side surface is a gallium face in the surface layer of which gallium atoms are located, and the field effect transistor has: a gate insulating film formed on the first side surface; and a gate electrode formed in the trench and covering the gate insulating film.
    Type: Application
    Filed: September 22, 2021
    Publication date: May 5, 2022
    Applicant: FUJI ELECTRIC CO., LTD.
    Inventors: Katsunori UENO, Yuki OHUCHI
  • Publication number: 20210288148
    Abstract: A nitride semiconductor device includes a GaN-based semiconductor layer; and an insulating film provided on a first surface of the GaN-based semiconductor layer, the insulating film containing O atoms, and other constituent atoms other than O. An interface between the GaN-based semiconductor layer and the insulating film has a terminating species which terminates a dangling bond of a Ga atom, the terminating species has an outermost electron shell in which one electron is deficient from an allowed number of outermost electrons, and is an atom or molecule having stronger bond to the Ga atom than a H atom, an amount of Ga—O bonds is greater than an amount of bonds between the Ga atoms and the other constituent atoms.
    Type: Application
    Filed: February 26, 2021
    Publication date: September 16, 2021
    Applicant: FUJI ELECTRIC CO., LTD.
    Inventors: Yuki OHUCHI, Katsunori UENO