Patents by Inventor Shinya Takashima

Shinya Takashima 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: 10615293
    Abstract: A diode is provided, the diode including: a semiconductor layer of a first conductivity type, configured to have a trench structure and be an epitaxial layer of a wide gap semiconductor; a semiconductor layer of a second conductivity type, configured to be at least in contact with a side wall of the trench structure and be an epitaxial layer of the wide gap semiconductor; and an electrode configured to be in contact with the semiconductor layer of the first conductivity type and the semiconductor layer of the second conductivity type, on the semiconductor layer of the first conductivity type and the semiconductor layer of the second conductivity type.
    Type: Grant
    Filed: October 30, 2018
    Date of Patent: April 7, 2020
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Ryo Tanaka, Shinya Takashima, Katsunori Ueno, Masaharu Edo
  • Publication number: 20200026837
    Abstract: According to at least one example embodiment of the present invention, provided is a face authentication system including: a criterion setting unit that sets a criterion of face authentication performed on a user so as to be different in accordance with a state of an access target system accessed by the user; and a face authentication unit that performs face authentication of the user based on the criterion.
    Type: Application
    Filed: September 26, 2019
    Publication date: January 23, 2020
    Inventors: Shinya TAKASHIMA, Shizuo SAKAMOTO
  • Publication number: 20200019692
    Abstract: According to at least one example embodiment of the present invention, provided. is a face authentication system including: a criterion setting unit that sets a criterion of face authentication performed on a user so as to be different in accordance with a state of an access target system accessed by the user; and a face authentication unit that performs face authentication of the user based on the criterion.
    Type: Application
    Filed: September 26, 2019
    Publication date: January 16, 2020
    Inventors: Shinya TAKASHIMA, Shizuo SAKAMOTO
  • Publication number: 20190304788
    Abstract: A nitride semiconductor device is provide, the nitride semiconductor device including: an epitaxial layer; and an ion implantation layer that is provided on the epitaxial layer over a continuous depth range that extends over 100 nm or longer, and has a P type doping concentration equal to or higher than 1×1017 cm?3, wherein the ion implantation layer has a region with a crystal defect density equal to or lower than 1×1016 cm?3, the region being located in a range which is on an upper-surface-side of an interface between the epitaxial layer and the ion implantation layer, and is within 100 nm from the interface.
    Type: Application
    Filed: March 12, 2019
    Publication date: October 3, 2019
    Inventors: Shinya TAKASHIMA, Ryo TANAKA, Yuta FUKUSHIMA, Hideaki TERANISHI
  • Patent number: 10374031
    Abstract: Provided is a semiconductor device including at least two isolation trench portions; a mesa region that is provided between the at least two isolation trench portions and includes a source region having a first conduction type, a base region having a second conduction type and at least a portion thereof provided below the source region, and a gate trench portion; and a contact layer that is an epitaxial layer provided at least in contact with side portions of the mesa region and bottom portions of the isolation trench portions positioned lower than the gate trench portion, and having a second-conduction-type impurity concentration higher than that of the base region, wherein the same impurities as in the contact layer are present in the source region, or the contact layer is provided higher than the source region.
    Type: Grant
    Filed: December 11, 2017
    Date of Patent: August 6, 2019
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Katsunori Ueno, Shinya Takashima, Masaharu Edo
  • Patent number: 10366891
    Abstract: A vertical semiconductor apparatus includes: a gallium nitride substrate; a gallium nitride semiconductor layer on the gallium nitride substrate; a p-type impurity region in the gallium nitride semiconductor layer and having an element to function as an acceptor for gallium nitride; an n-type impurity region in the p-type impurity region and having an element to function as a donor for gallium nitride; and an electrode provided contacting a rear surface of the gallium nitride substrate. The element to function as the donor in the n-type impurity region includes: a first impurity element to enter sites of gallium atoms in the gallium nitride semiconductor layer; and a second impurity element different from the first impurity element and to enter sites of nitrogen atoms in the gallium nitride semiconductor layer. In the n-type impurity region, a concentration of the first impurity element is higher than that of the second impurity element.
    Type: Grant
    Filed: March 27, 2018
    Date of Patent: July 30, 2019
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Shinya Takashima, Katsunori Ueno, Masaharu Edo
  • Publication number: 20190180017
    Abstract: According to at least one example embodiment of the present invention, provided is a face authentication system including: a criterion setting unit that sets a criterion of face authentication performed on a user so as to be different in accordance with a state of an access target system accessed by the user; and a face authentication unit that performs face authentication of the user based on the criterion.
    Type: Application
    Filed: February 14, 2019
    Publication date: June 13, 2019
    Applicant: NEC Corporation
    Inventors: Shinya TAKASHIMA, Shizuo Sakamoto
  • Publication number: 20190165187
    Abstract: A diode is provided, the diode including: a semiconductor layer of a first conductivity type, configured to have a trench structure and be an epitaxial layer of a wide gap semiconductor; a semiconductor layer of a second conductivity type, configured to be at least in contact with a side wall of the trench structure and be an epitaxial layer of the wide gap semiconductor; and an electrode configured to be in contact with the semiconductor layer of the first conductivity type and the semiconductor layer of the second conductivity type, on the semiconductor layer of the first conductivity type and the semiconductor layer of the second conductivity type.
    Type: Application
    Filed: October 30, 2018
    Publication date: May 30, 2019
    Inventors: Ryo TANAKA, Shinya TAKASHIMA, Katsunori UENO, Masaharu EDO
  • Publication number: 20190157448
    Abstract: A manufacturing method of a vertical GaN-based semiconductor device having: a GaN-based semiconductor substrate; a GaN-based semiconductor layer including a drift region having doping concentration of an n type impurity, which is lower than that of the GaN-based semiconductor substrate, and is provided on the GaN-based semiconductor substrate; and MIS structure having the GaN-based semiconductor layer, an insulating film contacting the GaN-based semiconductor layer, and a conductive portion contacting the insulating film, the method includes: implanting an n type dopant in a back surface of the GaN-based semiconductor substrate after forming of the MIS structure, and annealing the GaN-based semiconductor substrate after the implanting of the n type dopant.
    Type: Application
    Filed: November 1, 2018
    Publication date: May 23, 2019
    Inventors: Shinya TAKASHIMA, Katsunori UENO, Masaharu EDO
  • Publication number: 20190131409
    Abstract: Provided is a manufacturing method of a semiconductor device including a vertical MOSFET having a planar gate. The manufacturing method of a semiconductor device includes forming a n-type gallium nitride layer on a gallium nitride monocrystalline substrate, and forming an impurity-implanted region that contains impurities at a uniform concentration in a direction parallel to a main surface of the gallium nitride monocrystalline substrate, by ion-implanting the impurities into the n-type gallium nitride layer, where the impurities include at least one type selected from among magnesium, beryllium, calcium and zinc. Here, at least part of the impurity-implanted region serves as a channel forming region of the vertical MOSFET.
    Type: Application
    Filed: December 26, 2018
    Publication date: May 2, 2019
    Inventors: Katsunori UENO, Shinya TAKASHIMA
  • Publication number: 20190115215
    Abstract: A vertical semiconductor apparatus includes: a gallium nitride substrate; a gallium nitride semiconductor layer on the gallium nitride substrate; a p-type impurity region in the gallium nitride semiconductor layer and having an element to function as an acceptor for gallium nitride; an n-type impurity region in the p-type impurity region and having an element to function as a donor for gallium nitride; and an electrode provided contacting a rear surface of the gallium nitride substrate. The element to function as the donor in the n-type impurity region includes: a first impurity element to enter sites of gallium atoms in the gallium nitride semiconductor layer; and a second impurity element different from the first impurity element and to enter sites of nitrogen atoms in the gallium nitride semiconductor layer. In the n-type impurity region, a concentration of the first impurity element is higher than that of the second impurity element.
    Type: Application
    Filed: March 27, 2018
    Publication date: April 18, 2019
    Inventors: Shinya TAKASHIMA, Katsunori UENO, Masaharu EDO
  • Patent number: 10256292
    Abstract: In order to improve the dynamic characteristics of a vertical MOSFET using GaN, it is an objective of the present invention to reduce the resistance of a current path with a long hole movement distance in a p-type well. Provided is a vertical MOSFET including a gallium nitride layer having a main surface that is a non-polar surface; a p-type well region that is provided with a stripe shape in the main surface of the gallium nitride layer; and a stripe-shaped electrode provided above the p-type well region. Hole mobility is higher in a direction orthogonal to an extension direction of the stripe-shaped electrode than in the extension direction, among directions in a plane parallel to the main surface.
    Type: Grant
    Filed: October 27, 2016
    Date of Patent: April 9, 2019
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Shinya Takashima, Katsunori Ueno, Masaharu Edo
  • Patent number: 10181514
    Abstract: In a case where a semiconductor layer is epitaxially grown on a step shape formed due to CBL (current blocking layer) formation, the crystallinity of the semiconductor layer lowers. Also, a GaN layer that is epitaxially regrown on the CBL is not formed continuously by epitaxial growth, and therefore the crystallinity of the GaN layer lowers. A vertical semiconductor device manufacturing method is provided that comprises: a step of epitaxially growing a gallium nitride-based n-type semiconductor layer on a gallium nitride-based semiconductor substrate; a step of epitaxially growing a gallium nitride-based p-type semiconductor layer on the n-type semiconductor layer; and a step of ion-implanting p-type impurities to form a p+-type embedded region selectively in a predetermined depth range across the boundary between the n-type semiconductor layer and the p-type semiconductor layer.
    Type: Grant
    Filed: September 29, 2017
    Date of Patent: January 15, 2019
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Hideaki Matsuyama, Shinya Takashima, Katsunori Ueno, Takuro Inamoto, Masaharu Edo
  • Publication number: 20190006184
    Abstract: A gallium nitride based semiconductor device is provided, where when a thickness of a transition layer is defined as the followings, the thickness of the transition layer is less than 1.5 nm: (i) a distance between a depth position at which an atomic composition of nitrogen element constituting the gallium nitride based semiconductor layer is ½ relative to that at a position on the GaN based semiconductor layer side sufficiently away from the transition layer, and a depth position at which an atomic composition of a metal element is ½ of a value of a maximum if an atomic composition of the metal element constituting an insulating layer has the maximum, or a depth position at which an atomic composition of the metal element is ½ relative to that at a position on the insulating layer side sufficiently away from the transition layer if not having the maximum.
    Type: Application
    Filed: June 28, 2018
    Publication date: January 3, 2019
    Inventors: Hideaki MATSUYAMA, Shinya TAKASHIMA, Katsunori UENO, Ryo TANAKA, Masaharu EDO, Daisuke MORI, Hirotaka SUDA, Hideaki TERANISHI, Chizuru INOUE
  • Patent number: 10170564
    Abstract: Provided is a manufacturing method of a semiconductor device including a vertical MOSFET having a planar gate. The manufacturing method of a semiconductor device includes forming a n-type gallium nitride layer on a gallium nitride monocrystalline substrate, and forming an impurity-implanted region that contains impurities at a uniform concentration in a direction parallel to a main surface of the gallium nitride monocrystalline substrate, by ion-implanting the impurities into the n-type gallium nitride layer, where the impurities include at least one type selected from among magnesium, beryllium, calcium and zinc. Here, at least part of the impurity-implanted region serves as a channel forming region of the vertical MOSFET.
    Type: Grant
    Filed: May 30, 2017
    Date of Patent: January 1, 2019
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Katsunori Ueno, Shinya Takashima
  • Patent number: 10141192
    Abstract: When a nitride semiconductor layer into which impurity ions have been implanted is subjected to annealing after a protective film is provided on the nitride semiconductor layer, vacancy defects may be disadvantageously prevented from escaping outside through the surface of the nitride semiconductor layer and disappearing. A manufacturing method of a semiconductor device including a nitride semiconductor layer is provided. The manufacturing method includes implanting impurities into the nitride semiconductor layer, performing a first annealing on the nitride semiconductor layer at a first temperature within an atmosphere of a nitrogen atom containing gas without providing a protective film on the nitride semiconductor layer, forming the protective film on the nitride semiconductor layer after the first annealing, and after the protective film is formed, performing a second annealing on the nitride semiconductor layer at a second temperature that is higher than the first temperature.
    Type: Grant
    Filed: April 27, 2017
    Date of Patent: November 27, 2018
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Shinya Takashima, Katsunori Ueno, Masaharu Edo
  • Patent number: 10128106
    Abstract: When a defect region is present near the pn junction in a GaN layer, lattice defects are present in the depletion layer. Therefore, when a reverse bias is applied to the pn junction, the defects in the depletion layer cause the generated current to flow as a leakage current. The leakage current flowing through the depletion layer can cause a decrease in the withstand voltage at the pn junction. Provided is a semiconductor device using gallium nitride, including a gallium nitride layer including an n-type region. The gallium nitride layer includes a first p-type well region and a second p-type well region that is provided on at least a portion of the first p-type well region and has a peak region with a higher p-type impurity concentration than the first p-type well region.
    Type: Grant
    Filed: January 27, 2017
    Date of Patent: November 13, 2018
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Shinya Takashima, Katsunori Ueno, Masaharu Edo
  • Patent number: 10121876
    Abstract: In case of performing annealing at a temperature of 1300° C. or higher, it is not possible to sufficiently suppress escape of nitrogen from a GaN layer even if a cap layer is provided thereon. Thereby, the front surface of the GaN layer is roughened. A semiconductor device manufacturing method of manufacturing a semiconductor device having a nitride semiconductor layer is provided. The semiconductor device manufacturing method includes: implanting, into a predetermined region of the nitride semiconductor layer, n-type or p-type impurities relative to the nitride semiconductor layer; forming, by atomic layer deposition, a first protective film containing a nitride on and in direct contact with at least the predetermined region; and annealing the nitride semiconductor layer and the first protective film at a temperature of 1300° C. or higher.
    Type: Grant
    Filed: May 30, 2017
    Date of Patent: November 6, 2018
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Shinya Takashima, Katsunori Ueno, Masaharu Edo
  • Publication number: 20180175138
    Abstract: Provided is a semiconductor device including at least two isolation trench portions; a mesa region that is provided between the at least two isolation trench portions and includes a source region having a first conduction type, a base region having a second conduction type and at least a portion thereof provided below the source region, and a gate trench portion; and a contact layer that is an epitaxial layer provided at least in contact with side portions of the mesa region and bottom portions of the isolation trench portions positioned lower than the gate trench portion, and having a second-conduction-type impurity concentration higher than that of the base region, wherein the same impurities as in the contact layer are present in the source region, or the contact layer is provided higher than the source region.
    Type: Application
    Filed: December 11, 2017
    Publication date: June 21, 2018
    Inventors: Katsunori UENO, Shinya TAKASHIMA, Masaharu EDO
  • Publication number: 20180097063
    Abstract: In a case where a semiconductor layer is epitaxially grown on a step shape formed due to CBL (current blocking layer) formation, the crystallinity of the semiconductor layer lowers. Also, a GaN layer that is epitaxially regrown on the CBL is not formed continuously by epitaxial growth, and therefore the crystallinity of the GaN layer lowers. A vertical semiconductor device manufacturing method is provided that comprises: a step of epitaxially growing a gallium nitride-based n-type semiconductor layer on a gallium nitride-based semiconductor substrate; a step of epitaxially growing a gallium nitride-based p-type semiconductor layer on the n-type semiconductor layer; and a step of ion-implanting p-type impurities to form a p+-type embedded region selectively in a predetermined depth range across the boundary between the n-type semiconductor layer and the p-type semiconductor layer.
    Type: Application
    Filed: September 29, 2017
    Publication date: April 5, 2018
    Inventors: Hideaki MATSUYAMA, Shinya TAKASHIMA, Katsunori UENO, Takuro INAMOTO, Masaharu EDO