Patents by Inventor Yuichi Oshima

Yuichi Oshima 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: 11804519
    Abstract: A crystalline multilayer structure having a high-quality crystalline layer and a semiconductor device employing such a crystalline multilayer structure are provided. A crystalline multilayer structure, including a first crystalline layer having a first crystal, and a second crystalline layer stacked on the first crystalline layer and having a second crystal, wherein the first crystal includes polycrystalline ?-Ga2O3 and the second crystal is a single crystal of a crystalline oxide.
    Type: Grant
    Filed: April 26, 2021
    Date of Patent: October 31, 2023
    Assignees: FLOSFIA INC., NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Yuichi Oshima, Katsuaki Kawara
  • Patent number: 11694894
    Abstract: A high-quality crystalline film having less impurity of Si and the like and useful in semiconductor devices is provided. A crystalline film containing a crystalline metallic oxide including gallium as a main component, wherein the crystalline film includes a Si in a content of 2×1015 cm?3 or less.
    Type: Grant
    Filed: April 26, 2021
    Date of Patent: July 4, 2023
    Assignee: FLOSFIA INC.
    Inventors: Yuichi Oshima, Katsuaki Kawara
  • Publication number: 20230203711
    Abstract: Provided are: a GaN crystal used in a substrate for a nitride semiconductor device having a horizontal device structure, such as a GaN-HEMT; and a GaN substrate used for the production of a nitride semiconductor device having a horizontal device structure, such as a GaN-HEMT. The GaN crystal and the GaN substrate each include a surface having an inclination of 10° or less from a (0001) crystal plane and an area of 5 cm2 or more, and have an Mn concentration of 1.0 × 1016 atoms/cm3 or higher but lower than 1.0 × 1019 atoms/cm3 and a total donor impurity concentration of lower than 5.0 × 1016 atoms/cm3.
    Type: Application
    Filed: February 21, 2023
    Publication date: June 29, 2023
    Applicants: MITSUBISHI CHEMICAL CORPORATION, NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Yusuke TSUKADA, Yuichi Oshima, Yuuki Enatsu
  • Publication number: 20220189769
    Abstract: There is provided a crystalline film including, a crystalline metal oxide as a major component; a corundum structure; a dislocation density of 1×107 cm?2 or less; and a surface area of 10 mm2 or more. There is provided a method of producing a crystalline film comprising, forming a first lateral crystal growth layer on a substrate by first lateral crystal growth; placing a mask on the first lateral crystal growth layer; and forming a second lateral crystal growth layer by second lateral crystal growth.
    Type: Application
    Filed: March 2, 2022
    Publication date: June 16, 2022
    Inventors: Katsuaki KAWARA, Yuichi OSHIMA, Mitsuru OKIGAWA
  • Publication number: 20210384336
    Abstract: Provided are a GaN crystal used in a substrate for a nitride semiconductor device having a horizontal device structure such as GaN-HEMT, and a substrate used for production of a nitride semiconductor device having a horizontal device structure such as GaN-HEMT. The Gab crystal has a (0001) surface having an area of not less than 5 cm2, the (0001) surface having an inclination of not more than 10° with respect to the (0001) crystal plane, wherein the Fe concentration is not less than 5×1017 atoms/cm3 and less than 1×109 atoms/cm3, and wherein the total donor impurity concentration is less than 5×1016 atoms/cm3.
    Type: Application
    Filed: August 19, 2021
    Publication date: December 9, 2021
    Applicants: MITSUBISHI CHEMICAL CORPORATION, NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Yuuki ENATSU, Yuichi OSHIMA
  • Publication number: 20210335995
    Abstract: A crystalline multilayer structure having a high-quality crystalline layer and a semiconductor device employing such a crystalline multilayer structure are provided. A crystalline multilayer structure, including a first crystalline layer having a first crystal, and a second crystalline layer stacked on the first crystalline layer and having a second crystal, wherein the first crystal includes polycrystalline ?-Ga2O3 and the second crystal is a single crystal of a crystalline oxide.
    Type: Application
    Filed: April 26, 2021
    Publication date: October 28, 2021
    Inventors: Yuichi OSHIMA, Katsuaki KAWARA
  • Publication number: 20210335609
    Abstract: A high-quality crystalline film having less impurity of Si and the like and useful in semiconductor devices is provided. A crystalline film containing a crystalline metallic oxide including gallium as a main component, wherein the crystalline film includes a Si in a content of 2×1015 cm?3 or less.
    Type: Application
    Filed: April 26, 2021
    Publication date: October 28, 2021
    Inventors: Yuichi OSHIMA, Katsuaki KAWARA
  • Patent number: 10460934
    Abstract: According to an aspect of a present inventive subject matter, a crystalline film includes a crystalline metal oxide as a major component, the crystalline film includes a corundum structure, a surface area that is 9 ?m2 or more, and a dislocation density that is less than 5×106 cm?2.
    Type: Grant
    Filed: August 21, 2018
    Date of Patent: October 29, 2019
    Assignees: FLOSFIA INC., NATIONAL INSTITUTE FOR MATERIALS SCIENCE, KYOTO UNIVERSITY, SAGA UNIVERSITY
    Inventors: Yuichi Oshima, Shizuo Fujita, Kentaro Kaneko, Makoto Kasu, Katsuaki Kawara, Takashi Shinohe, Tokiyoshi Matsuda, Toshimi Hitora
  • Publication number: 20190055667
    Abstract: According to an aspect of a present inventive subject matter, a method for producing a crystalline film includes; gasifying a metal source containing a metal to turn the metal source into a metal-containing raw-material gas; supplying the metal-containing raw-material gas and an oxygen-containing raw-material gas into a reaction chamber onto a substrate including a buffer layer; and supplying a reactive gas into the reaction chamber onto the substrate to form a crystalline film on the substrate under a gas flow of the reactive gas.
    Type: Application
    Filed: August 21, 2018
    Publication date: February 21, 2019
    Inventors: Yuichi OSHIMA, Shizuo FUJITA, Kentaro KANEKO, Makoto KASU, Katsuaki KAWARA, Takashi SHINOHE, Tokiyoshi MATSUDA, Toshimi HITORA
  • Publication number: 20190057866
    Abstract: According to an aspect of a present inventive subject matter, a crystal includes: a corundum-structured oxide semiconductor as a major component, the corundum-structured oxide semiconductor including gallium and/or indium and doped with a dopant including germanium; a principal plane; a carrier concentration that is 1×1018/cm3 or more; and an electron mobility that is 20 cm2/Vs or more.
    Type: Application
    Filed: August 21, 2018
    Publication date: February 21, 2019
    Inventors: Yuichi OSHIMA, Shizuo FUJITA, Kentaro KANEKO, Makoto KASU, Katsuaki KAWARA, Takashi SHINOHE, Tokiyoshi MATSUDA, Toshimi HITORA
  • Publication number: 20190057865
    Abstract: According to an aspect of a present inventive subject matter, a crystalline film includes a crystalline metal oxide as a major component, the crystalline film includes a corundum structure, a surface area that is 9 ?m2 or more, and a dislocation density that is less than 5×106cm?2.
    Type: Application
    Filed: August 21, 2018
    Publication date: February 21, 2019
    Inventors: Yuichi OSHIMA, Shizuo FUJITA, Kentaro KANEKO, Makoto KASU, Katsuaki KAWARA, Takashi SHINOHE, Tokiyoshi MATSUDA, Toshimi HITORA
  • Publication number: 20190055646
    Abstract: According to an aspect of a present inventive subject matter, a method for producing a crystalline film includes gasifying a metal source to turn the metal source into a metal-containing raw-material gas; supplying the metal-containing raw-material gas and an oxygen-containing raw-material gas into a reaction chamber onto a substrate; and supplying a reactive gas into the reaction chamber onto the substrate to form a crystalline film under a gas flow of the reactive gas.
    Type: Application
    Filed: August 21, 2018
    Publication date: February 21, 2019
    Inventors: Yuichi OSHIMA, Katsuaki KAWARA, Takashi SHINOHE, Tokiyoshi MATSUDA, Toshimi HITORA
  • Patent number: 10060047
    Abstract: A nitride semiconductor crystal producing method, includes growing a nitride semiconductor crystal over a seed crystal substrate, while applying an etching action to an outer end of the seed crystal substrate during the growing of the nitride semiconductor crystal.
    Type: Grant
    Filed: January 24, 2014
    Date of Patent: August 28, 2018
    Assignee: SUMITOMO CHEMICAL COMPANY, LIMITED
    Inventors: Hajime Fujikura, Taichiroo Konno, Yuichi Oshima
  • Patent number: 9246049
    Abstract: A nitride-based semiconductor substrate has a diameter of 25 mm or more, a thickness of 250 micrometers or more, a n-type carrier concentration of 1.2×1018 cm?3 or more and 3×1019 cm?3 or less, and a thermal conductivity of 1.2 W/cmK or more and 3.5 W/cmK or less. Alternatively, the substrate has an electron mobility ? [cm2/Vs] of more than a value represented by loge?=17.7?0.288 logen and less than a value represented by loge?=18.5?0.288 logen, where the substrate has a n-type carrier concentration n [cm?3] that is 1.2×1018 cm?3 or more and 3×1019 cm?3 or less.
    Type: Grant
    Filed: August 19, 2008
    Date of Patent: January 26, 2016
    Assignee: SCIOCS COMPANY LIMITED
    Inventor: Yuichi Oshima
  • Patent number: 8975230
    Abstract: Described herein are methods and compositions related to the discovery that the Follistatin-like 1 protein (Fstl-1) has metabolic and cardioprotective effects in vivo. Fstl-1 and portions and derivatives or variants thereof can be used to treat or prevent metabolic diseases or disorders and to treat or prevent cardiac damage caused by interrupted cardiac muscle blood supply.
    Type: Grant
    Filed: October 5, 2012
    Date of Patent: March 10, 2015
    Assignee: Trustees of Boston University
    Inventors: Kenneth Walsh, Yuichi Oshima, Noriyuki Ouchi
  • Patent number: 8829651
    Abstract: A nitride-based semiconductor substrate has a diameter of 25 mm or more, a thickness of 250 micrometers or more, a n-type carrier concentration of 1.2×1018 cm?3 or more and 3×1019 cm?3 or less, and a thermal conductivity of 1.2 W/cmK or more and 3.5 W/cmK or less. Alternatively, the substrate has an electron mobility ? [cm2/Vs] of more than a value represented by loge ?=17.7?0.288 loge n and less than a value represented by loge ?=18.5?0.288 loge n, where the substrate has a n-type carrier concentration n [cm?3] that is 1.2×1018 cm?3 or more and 3×1019 cm?3 or less.
    Type: Grant
    Filed: April 5, 2006
    Date of Patent: September 9, 2014
    Assignee: Hitachi Metals, Ltd.
    Inventor: Yuichi Oshima
  • Patent number: 8786052
    Abstract: A nitride semiconductor crystal producing method, a nitride semiconductor epitaxial wafer, and a nitride semiconductor freestanding substrate, by which it is possible to suppress the occurrence of cracking in the nitride semiconductor crystal and to ensure the enhancement of the yield of the nitride semiconductor crystal. The nitride semiconductor crystal producing method includes growing a nitride semiconductor crystal over a seed crystal substrate, while applying an etching action to an outer end of the seed crystal substrate during the growing of the nitride semiconductor crystal.
    Type: Grant
    Filed: September 11, 2012
    Date of Patent: July 22, 2014
    Assignee: Hitachi Metals, Ltd.
    Inventors: Hajime Fujikura, Taichiroo Konno, Yuichi Oshima
  • Publication number: 20140196660
    Abstract: A nitride semiconductor crystal producing method, includes growing a nitride semiconductor crystal over a seed crystal substrate, while applying an etching action to an outer end of the seed crystal substrate during the growing of the nitride semiconductor crystal.
    Type: Application
    Filed: January 24, 2014
    Publication date: July 17, 2014
    Applicant: Hitachi Metals, Ltd.
    Inventors: Hajime FUJIKURA, Taichiroo KONNO, Yuichi OSHIMA
  • Patent number: 8715413
    Abstract: The invention provides a method for manufacturing a Group III nitride semiconductor crystal. The method includes the steps of preparing a seed crystal and performing a convex surface-growing step to grow the group III nitride semiconductor crystal. The growth surface of the group III nitride semiconductor crystal is constituted only by a plurality of surfaces not vertical to a growth direction and the group III nitride semiconductor crystal grows while forming a convex shape as a whole by the growth surface constituted of the plurality of surfaces. The invention also provides a method for manufacturing a group III nitride semiconductor substrate.
    Type: Grant
    Filed: June 16, 2010
    Date of Patent: May 6, 2014
    Assignee: Hitachi Cable, Ltd.
    Inventor: Yuichi Oshima
  • Patent number: 8690636
    Abstract: A method of making a compound semiconductor substrate includes providing a GaN compound semiconductor single crystal ingot, and cutting the ingot with a cutter to form a GaN single crystal substrate. The cutting is performed while controlling a temperature in a contact portion between the ingot and the cutter to be not more than 160° C. such that a cut surface of the GaN single crystal substrate has an arithmetical mean waviness (Wa) not more than 9 ?m.
    Type: Grant
    Filed: March 19, 2010
    Date of Patent: April 8, 2014
    Assignee: Hitachi Cable, Ltd.
    Inventor: Yuichi Oshima