Patents by Inventor Kazuma ETO

Kazuma ETO 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).

  • n-Type 4H—SiC single crystal substrate and method of producing n-type 4H—SiC single crystal substrate
    Patent number: 11655561
    Abstract: In an n-type 4H-SiC single crystal substrate of the present disclosure, the concentration of the element N as a donor and the concentration of the element B as an acceptor are both 3×1018/cm3 or more, and a threading dislocation density is less than 4,000/cm2.
    Type: Grant
    Filed: August 28, 2019
    Date of Patent: May 23, 2023
    Assignee: SHOWA DENKO K.K.
    Inventors: Hiromasa Suo, Kazuma Eto, Tomohisa Kato
  • Method for producing p-type 4H-SiC single crystal
    Patent number: 11542631
    Abstract: A method for producing a p-type 4H—SiC single crystal includes sublimating a nitrided aluminum raw material and a SiC raw material. Further, there is a stacking of a SiC single crystal, which is co-doped with aluminum and nitrogen, on one surface of a seed crystal.
    Type: Grant
    Filed: June 29, 2020
    Date of Patent: January 3, 2023
    Assignees: NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY, SHOWA DENKO K.K., DENSO CORPORATION
    Inventors: Kazuma Eto, Tomohisa Kato, Hiromasa Suo, Yuichiro Tokuda
  • n-Type SiC single crystal substrate, method for producing same and SiC epitaxial wafer
    Patent number: 10892334
    Abstract: An n-type SiC single crystal substrate of the present invention is provided which is a substrate doped with both a donor and an acceptor, and has a difference between a donor concentration and an acceptor concentration in an outer peripheral portion which is smaller than a difference between a donor concentration and an acceptor concentration in a central portion, and is smaller than 3.0×1019/cm3.
    Type: Grant
    Filed: September 25, 2017
    Date of Patent: January 12, 2021
    Assignee: SHOWA DENKO K.K.
    Inventors: Kazuma Eto, Hiromasa Suo, Tomohisa Kato
  • METHOD FOR PRODUCING P-TYPE 4H-SIC SINGLE CRYSTAL
    Publication number: 20200325595
    Abstract: A method for producing a p-type 4H-SiC single crystal includes sublimating a nitrided aluminum raw material and a SiC raw material. Further, there is a stacking of a SiC single crystal, which is co-doped with aluminum and nitrogen, on one surface of a seed crystal.
    Type: Application
    Filed: June 29, 2020
    Publication date: October 15, 2020
    Applicants: NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY, SHOWA DENKO K.K., DENSO CORPORATION
    Inventors: Kazuma ETO, Tomohisa KATO, Hiromasa SUO, Yuichiro TOKUDA
  • n-TYPE 4H-SiC SINGLE CRYSTAL SUBSTRATE AND METHOD OF PRODUCING n-TYPE 4H-SiC SINGLE CRYSTAL SUBSTRATE
    Publication number: 20200071849
    Abstract: In an n-type 4H-SiC single crystal substrate of the present disclosure, the concentration of the element N as a donor and the concentration of the element B as an acceptor are both 3×1018/cm3 or more, and a threading dislocation density is less than 4,000/cm2.
    Type: Application
    Filed: August 28, 2019
    Publication date: March 5, 2020
    Applicant: SHOWA DENKO K.K.
    Inventors: Hiromasa SUO, Kazuma ETO, Tomohisa KATO
  • SILICON CARBIDE EPITAXIAL WAFER AND SILICON CARBIDE SEMICONDUCTOR DEVICE
    Publication number: 20190333998
    Abstract: A high quality silicon carbide epitaxial wafer using a p-type silicon carbide single crystal substrate of low resistivity. The silicon carbide epitaxial wafer includes a p-type 4H—SiC single crystal substrate that has a first main surface having an off angle with respect to (0001) plane, and has a resistivity of less than 0.4 ?cm, and a silicon carbide epitaxial layer that is disposed on the first main surface of the p-type 4H—SiC single crystal substrate, in which an off direction of the off angle is the <01-10> direction.
    Type: Application
    Filed: December 19, 2018
    Publication date: October 31, 2019
    Inventors: Keiko MASUMOTO, Takashi MITANI, Kazuma ETO, Kazutoshi KOJIMA, Tomohisa KATO
  • n-TYPE SiC SINGLE CRYSTAL SUBSTRATE, METHOD FOR PRODUCING SAME AND SiC EPITAXIAL WAFER
    Publication number: 20190252504
    Abstract: An n-type SiC single crystal substrate of the present invention is provided which is a substrate doped with both a donor and an acceptor, and has a difference between a donor concentration and an acceptor concentration in an outer peripheral portion which is smaller than a difference between a donor concentration and an acceptor concentration in a central portion, and is smaller than 3.0×1019/cm3.
    Type: Application
    Filed: September 25, 2017
    Publication date: August 15, 2019
    Applicant: SHOWA DENKO K.K.
    Inventors: Kazuma ETO, Hiromasa SUO, Tomohisa KATO
  • P-TYPE 4H-SIC SINGLE CRYSTAL AND METHOD FOR PRODUCING P-TYPE 4H-SIC SINGLE CRYSTAL
    Publication number: 20180274125
    Abstract: The present invention provides a p-type 4H—SiC single crystal, which is doped with both aluminum and nitrogen, and has a nitrogen concentration of 2.0×1019/cm3 or more.
    Type: Application
    Filed: September 29, 2016
    Publication date: September 27, 2018
    Applicants: NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY, SHOWA DENKO K.K., DENSO CORPORATION
    Inventors: Kazuma ETO, Tomohisa KATO, Hiromasa SUO, Yuichiro TOKUDA