Patents Assigned to Koha Co., Ltd.
  • Publication number: 20200220052
    Abstract: As one of purposes, the present invention provides: a single-crystal phosphor which can exhibit excellent properties under high-temperature conditions; and a light-emitting device in which the phosphor is used. As one embodiment, a single-crystal phosphor is provided, which has a chemical composition represented by the compositional formula: Y1-x-y-zLuxGdyCez)3+aAl5-aO12(0?x?0.9994, 0?y?0.0669, 0.0002?z?0.0067,?0.016?a?0.315).
    Type: Application
    Filed: March 17, 2020
    Publication date: July 9, 2020
    Applicants: KOHA CO., LTD., NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Daisuke INOMATA, Kazuo AOKI, Kiyoshi SHIMAMURA, Encarnacion Antonia GARCIA VILLORA
  • Publication number: 20200200347
    Abstract: A light emitting device includes a laser diode that emits a blue light, and a wavelength conversion part that absorbs a part of light emitted from the laser diode and converts a wavelength thereof. The wavelength conversion part includes a YAG-based single crystal phosphor. Irradiance of light emitted from the laser diode and irradiated on the wavelength conversion part is not less than 80 W/mm2.
    Type: Application
    Filed: December 27, 2016
    Publication date: June 25, 2020
    Applicants: TAMURA CORPORATION, KOHA CO., LTD.
    Inventors: Mikihiko UWANI, Akira ITO, Hiroyuki SAWANO, Kentaro TONE, Hiroaki SANO, Daisuke INOMATA, Kazuyuki IIZUKA
  • Patent number: 10526721
    Abstract: Provided is a method for growing a ?-Ga2O3-based single crystal, whereby it becomes possible to grow a ?-Ga2O3-based single crystal having a small variation in crystal structure and also having a high quality in the direction of a b axis. In one embodiment, a method for growing a ?-Ga2O3-based single crystal includes growing a plate-shaped Sn doped ?-Ga2O3-based single crystal in the direction of the b axis using a seed crystal.
    Type: Grant
    Filed: March 31, 2014
    Date of Patent: January 7, 2020
    Assignees: KOHA CO., LTD., TAMURA CORPORATION
    Inventors: Shinya Watanabe, Kazuyuki Iizuka, Kei Doioka, Haruka Matsubara, Takekazu Masui
  • Patent number: 10340429
    Abstract: According to one embodiment of the present invention, the light emitting device includes an LED element, a side wall which surrounds the LED element, a phosphor layer which is fixed to the side wall with an adhesive layer therebetween, and is positioned above the LED element, and a metal pad as a heat dissipating member. The side wall includes an insulating base which surrounds the LED element and a metal layer which is formed on a side surface at the LED element side of the base, and is in contact with the metal pad and the adhesive layer. The adhesive layer includes a resin layer that includes a resin containing particles which have higher thermal conductivity than the resin or a layer that includes solder.
    Type: Grant
    Filed: March 16, 2017
    Date of Patent: July 2, 2019
    Assignees: KOHA CO., LTD., TAMURA CORPORATION, NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Daisuke Inomata, Hiroaki Sano, Seitaro Yoshida, Kazuo Aoki, Kiyoshi Shimamura, Encarnacion Antonia Garcia Villora
  • Patent number: 10196756
    Abstract: A ?-Ga2O3-based single-crystal substrate includes a ?-Ga2O3-based single crystal, and a principal surface being a plane parallel to a b-axis of the ?-Ga2O3-based single crystal. A maximum value of ?? on an arbitrary straight line on the principal surface that passes through a center of the principal surface is not more than 0.7264. The ?? is a difference between a maximum value and a minimum value of values obtained by subtracting ?a from ?s at each of measurement positions, where ?s represents an angle defined by an X-ray incident direction and the principal surface at a peak position of an X-ray rocking curve on the straight line and ?a represents an angle on an approximated straight line obtained by using least-squares method to linearly approximate a curve representing a relationship between the ?s and the measurement positions thereof.
    Type: Grant
    Filed: June 29, 2015
    Date of Patent: February 5, 2019
    Assignees: TAMURA CORPORATION, KOHA CO., LTD.
    Inventors: Shinya Watanabe, Kimiyoshi Koshi, Yu Yamaoka, Kazuyuki Iizuka, Masaru Takizawa, Takekazu Masui
  • Patent number: 9926646
    Abstract: A method for growing a ?-Ga2O3-based single crystal, can provide a plate-shaped ?-Ga2O3-based single crystal having high crystal quality. In one embodiment, a method for growing a ?-Ga2O3-based single crystal employing an EFG method is provided, the method including: bringing a plate-shaped seed crystal into contact with a Ga2O3-based melt, wherein the plate-shaped seed crystal includes a ?-Ga2O3-based single crystal having a defect density of not more than 5×105 /cm2 in the whole region; and pulling up the seed crystal to grow a ?-Ga2O3-based single crystal.
    Type: Grant
    Filed: October 9, 2013
    Date of Patent: March 27, 2018
    Assignees: TAMURA CORPORATION, KOHA CO., LTD.
    Inventors: Shinya Watanabe, Daiki Wakimoto, Kazuyuki Iizuka, Kimiyoshi Koshi, Takekazu Masui
  • Patent number: 9926647
    Abstract: Provided are: a method for producing a ?-Ga2O3 substrate of which changes in donor concentration in a reducing atmosphere or an inert gas atmosphere are suppressed; and a method for producing a crystal laminate structure that can epitaxially grow a high-quality crystal film having low variability of quality in a reducing atmosphere or an inert gas atmosphere. The method for producing a ?-Ga2O3 substrate includes a step for cutting out a ?-Ga2O3 substrate from a ?-Ga2O3 crystal containing a group IV element; annealing processing in an atmosphere containing a reducing atmosphere and/or an inert gas atmosphere is performed on the ?-Ga2O3 crystal before cutting out the ?-Ga2O3 substrate, or on the cut-out ?-Ga2O3 substrate.
    Type: Grant
    Filed: October 12, 2012
    Date of Patent: March 27, 2018
    Assignees: TAMURA CORPORATION, KOHA CO., LTD.
    Inventors: Takekazu Masui, Yu Yamaoka
  • Patent number: 9915009
    Abstract: Provided is one embodiment which is a method for growing a ?-Ga2O3-based single crystal including contacting a flat plate-shaped seed crystal with a Ga2O3-based melt, and pulling up the seed crystal such that a flat plate-shaped ?-Ga2O3-based single crystal having a principal surface which intersects a surface is grown without inheriting a crystal information of a vaporized material of the Ga2O3-based melt adhered to the principal surface of the seed crystal, wherein when growing the ?-Ga2O3-based single crystal, a shoulder of the ?-Ga2O3-based single crystal is widened in a thickness direction (t) thereof.
    Type: Grant
    Filed: May 2, 2014
    Date of Patent: March 13, 2018
    Assignees: TAMURA CORPORATION, KOHA CO., LTD.
    Inventors: Kimiyoshi Koshi, Shinya Watanabe
  • Patent number: 9915010
    Abstract: Provided is one embodiment which is a method for growing a ?-Ga2O3-based single crystal which uses the EFG method and includes raising a Ga2O3 melt inside a crucible up to a die opening via a die slit such that a seed crystal is contacted with the Ga2O3-based melt in the opening of the die with a horizontal position of the seed crystal shifted in a width direction (W) from a center in the width direction (W) of the die, and pulling up the seed crystal contacting the Ga2O3-based melt so as to grown a ?-Ga2O3 single crystal.
    Type: Grant
    Filed: May 2, 2014
    Date of Patent: March 13, 2018
    Assignees: TAMURA CORPORATION, KOHA CO., LTD.
    Inventors: Kimiyoshi Koshi, Takekazu Masui, Masaru Takizawa
  • Patent number: 9903045
    Abstract: A method for growing a ?-Ga2O3-based single crystal, can provide a plate-shaped ?-Ga2O3-based single crystal having high crystal quality. In one embodiment, a method for growing a ?-Ga2O3-based single crystal employing an EFG method is provided, the method including: bringing a plate-shaped seed crystal into contact with a Ga2O3-based melt, wherein the plate-shaped seed crystal includes a ?-Ga2O3-based single crystal having a defect density of not more than 5×105 /cm2 in the whole region; and pulling up the seed crystal to grow a ?-Ga2O3-based single crystal.
    Type: Grant
    Filed: October 9, 2013
    Date of Patent: February 27, 2018
    Assignees: TAMURA CORPORATION, KOHA CO., LTD.
    Inventors: Shinya Watanabe, Daiki Wakimoto, Kazuyuki Iizuka, Kimiyoshi Koshi, Takekazu Masui
  • Publication number: 20170186923
    Abstract: According to one embodiment of the present invention, the light emitting device includes an LED element, a side wall which surrounds the LED element, a phosphor layer which is fixed to the side wall with an adhesive layer therebetween, and is positioned above the LED element, and a metal pad as a heat dissipating member. The side wall includes an insulating base which surrounds the LED element and a metal layer which is formed on a side surface at the LED element side of the base, and is in contact with the metal pad and the adhesive layer. The adhesive layer includes a resin layer that includes a resin containing particles which have higher thermal conductivity than the resin or a layer that includes solder.
    Type: Application
    Filed: March 16, 2017
    Publication date: June 29, 2017
    Applicants: KOHA CO., LTD., TAMURA CORPORATION, NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Daisuke INOMATA, Hiroaki SANO, Seitaro YOSHIDA, Kazuo AOKI, Kiyoshi SHIMAMURA, Encarnacion Antonia GARCIA VILLORA
  • Publication number: 20170152610
    Abstract: A ?-Ga2O3-based single-crystal substrate includes a ?-Ga2O3-based single crystal, and a principal surface being a plane parallel to a b-axis of the ?-Ga2O3-based single crystal. A maximum value of ?? on an arbitrary straight line on the principal surface that passes through a center of the principal surface is not more than 0.7264. The ?? is a difference between a maximum value and a minimum value of values obtained by subtracting ?a from ?s at each of measurement positions, where ?s represents an angle defined by an X-ray incident direction and the principal surface at a peak position of an X-ray rocking curve on the straight line and ?a represents an angle on an approximated straight line obtained by using least-squares method to linearly approximate a curve representing a relationship between the ?s and the measurement positions thereof.
    Type: Application
    Filed: June 29, 2015
    Publication date: June 1, 2017
    Applicants: TAMURA CORPORATION, KOHA CO., LTD.
    Inventors: Shinya WATANABE, Kimiyoshi KOSHI, Yu YAMAOKA, Kazuyuki IIZUKA, Masaru TAKIZAWA, Takekazu MASUI
  • Publication number: 20170137965
    Abstract: Provided is a gallium oxide substrate which has less linear pits. Obtained is a gallium oxide substrate wherein the average density of linear pits in a single crystal surface is 1,000 pits/cm2 or less.
    Type: Application
    Filed: July 1, 2015
    Publication date: May 18, 2017
    Applicants: TAMURA CORPORATION, KOHA CO., LTD.
    Inventors: Kimiyoshi KOSHI, Shinya WATANABE, Yu YAMAOKA, Makoto WATANABE
  • Patent number: 9634216
    Abstract: According to one embodiment of the present invention, the light emitting device includes an LED element, a side wall which surrounds the LED element, a phosphor layer which is fixed to the side wall with an adhesive layer therebetween, and is positioned above the LED element, and a metal pad as a heat dissipating member. The side wall includes an insulating base which surrounds the LED element and a metal layer which is formed on a side surface at the LED element side of the base, and is in contact with the metal pad and the adhesive layer. The adhesive layer includes a resin layer that includes a resin containing particles which have higher thermal conductivity than the resin or a layer that includes solder.
    Type: Grant
    Filed: August 8, 2014
    Date of Patent: April 25, 2017
    Assignees: Koha Co., Ltd., Tamura Corporation, National Institute for Materials Science
    Inventors: Daisuke Inomata, Hiroaki Sano, Seitaro Yoshida, Kazuo Aoki, Kiyoshi Shimamura, Encarnacion Antonia Garcia Villora
  • Patent number: 9431489
    Abstract: A ?-Ga2O3-based single crystal substrate includes an average dislocation density of less than 7.31×104 cm?2. The average dislocation density may be not more than 6.14×104 cm?2. The substrate may further include a main surface including a plane orientation of (?201), (101) or (001). The substrate may be free from any twinned crystal.
    Type: Grant
    Filed: February 27, 2015
    Date of Patent: August 30, 2016
    Assignees: TAMURA CORPORATION, KOHA CO., LTD.
    Inventors: Kimiyoshi Koshi, Shinya Watanabe, Masaru Takizawa, Yu Yamaoka, Makoto Watanabe, Takekazu Masui
  • Publication number: 20160240748
    Abstract: As one of purposes, the present invention provides: a single-crystal phosphor which can exhibit excellent properties under high-temperature conditions; and a light-emitting device in which the phosphor is used. As one embodiment, a single-crystal phosphor is provided, which has a chemical composition represented by the compositional formula: (Y1-x-y-zLuxGdyCez)3+aAl5-aO12(0?x?0.9994, 0?y?0.0669, 0.0002?z?0.0067, ?0.016?a?0.315).
    Type: Application
    Filed: October 20, 2014
    Publication date: August 18, 2016
    Applicants: KOHA CO., LTD., NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Daisuke Inomata, Kazuo Aoki, Kiyoshi Shimamura, Encarnacion Antonia Garcia Villora
  • Publication number: 20160190418
    Abstract: According to one embodiment of the present invention, the light emitting device includes an LED element, a side wall which surrounds the LED element, a phosphor layer which is fixed to the side wall with an adhesive layer therebetween, and is positioned above the LED element, and a metal pad as a heat dissipating member. The side wall includes an insulating base which surrounds the LED element and a metal layer which is formed on a side surface at the LED element side of the base, and is in contact with the metal pad and the adhesive layer. The adhesive layer includes a resin layer that includes a resin containing particles which have higher thermal conductivity than the resin or a layer that includes solder.
    Type: Application
    Filed: August 8, 2014
    Publication date: June 30, 2016
    Applicants: KOHA CO., LTD., TAMURA CORPORATION, NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Daisuke INOMATA, Hiroaki SANO, Seitaro YOSHIDA, Kazuo AOKI, Kiyoshi SHIMAMURA, Encarnacion Antonia GARCIA VILLORA
  • Patent number: 9349915
    Abstract: A ?-Ga2O3-based single crystal substrate includes a ?-Ga2O3-based single crystal. The ?-Ga2O3-based single crystal includes a full width at half maximum of an x-ray rocking curve of less than 75 seconds.
    Type: Grant
    Filed: February 26, 2015
    Date of Patent: May 24, 2016
    Assignees: TAMURA CORPORATION, KOHA CO., LTD.
    Inventors: Kimiyoshi Koshi, Shinya Watanabe, Masaru Takizawa, Yu Yamaoka, Daiki Wakimoto, Makoto Watanabe
  • Publication number: 20160122899
    Abstract: Provided is one embodiment which is a method for growing a ?-Ga2O3-based single crystal including contacting a flat plate-shaped seed crystal with a Ga2O3-based melt, and pulling up the seed crystal such that a flat plate-shaped ?-Ga2O3-based single crystal having a principal surface which intersects a surface is grown without inheriting a crystal information of a vaporized material of the Ga2O3-based melt adhered to the principal surface of the seed crystal, wherein when growing the ?-Ga2O3-based single crystal, a shoulder of the ?-Ga2O3-based single crystal is widened in a thickness direction (t) thereof.
    Type: Application
    Filed: May 2, 2014
    Publication date: May 5, 2016
    Applicants: KOHA CO., LTD., TAMURA CORPORATION
    Inventors: Kimiyoshi KOSHI, Shinya WATANABE
  • Publication number: 20160115621
    Abstract: Provided is one embodiment which is a method for growing a ?-Ga2O3-based single crystal which uses the EFG method and includes raising a Ga2O3 melt inside a crucible up to a die opening via a die slit such that a seed crystal is contacted with the Ga2O3-based melt in the opening of the die with a horizontal position of the seed crystal shifted in a width direction (W) from a center in the width direction (W) of the die, and pulling up the seed crystal contacting the Ga2O3-based melt so as to grown a ?-Ga2O3 single crystal.
    Type: Application
    Filed: May 2, 2014
    Publication date: April 28, 2016
    Applicants: TAMURA CORPORATION, KOHA CO., LTD.
    Inventors: Kimiyoshi KOSHI, Takekazu MASUI, Masaru TAKIZAWA