Patents by Inventor Tsutomu Nanataki

Tsutomu Nanataki 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).

  • Publication number: 20180179665
    Abstract: An oriented alumina substrate for epitaxial growth according to an embodiment of the present invention includes crystalline grains constituting a surface thereof, the crystalline grains having a tilt angle of 1° or more and 3° or less and an average sintered grain size of 20 ?m or more.
    Type: Application
    Filed: February 22, 2018
    Publication date: June 28, 2018
    Applicant: NGK INSULATORS, LTD.
    Inventors: Morimichi WATANABE, Kei SATO, Kiyoshi MATSUSHIMA, Tsutomu NANATAKI
  • Publication number: 20180179664
    Abstract: An oriented alumina substrate for epitaxial growth according to an embodiment of the present invention includes crystalline grains constituting a surface thereof, the crystalline grains having a tilt angle of 0.1° or more and less than 1.0° and an average sintered grain size of 10 ?m or more.
    Type: Application
    Filed: February 22, 2018
    Publication date: June 28, 2018
    Applicant: NGK INSULATORS, LTD.
    Inventors: Morimichi WATANABE, Kei SATO, Kiyoshi MATSUSHIMA, Tsutomu NANATAKI
  • Patent number: 9934968
    Abstract: There is provided a production method which enables stable formation of a p-type zinc oxide film and also is suitable for enlarging the area of the film. The method for producing a p-type zinc oxide film according to the present invention comprises the steps of: placing a target containing a zinc source and a substrate in a gas atmosphere containing a nitrogen source and an oxygen source and having a gas pressure of 0.1 Pa to 100 Pa, and exposing the target to arc discharge, thereby forming a precursor film containing zinc and oxygen on the substrate; and annealing the precursor film in an oxidizing atmosphere, thereby forming a p-type zinc oxide film.
    Type: Grant
    Filed: November 9, 2016
    Date of Patent: April 3, 2018
    Assignees: Nagoya Institute of Technology, NGK Insulators, Ltd.
    Inventors: Masaki Tanemura, Morimichi Watanabe, Jun Yoshikawa, Tsutomu Nanataki
  • Publication number: 20180044195
    Abstract: An alumina sintered body according to the present invention includes a surface having a degree of c-plane orientation of 5% or more, the degree of c-plane orientation being determined by a Lotgering method using an X-ray diffraction profile obtained through X-ray irradiation at 2?=20° to 70°. The alumina sintered body contains Mg and F, a Mg/F mass ratio is 0.05 to 3500, and a Mg content is 30 to 3500 ppm by mass. The alumina sintered body has a crystal grain size of 15 to 200 ?m. When a field of view of 370.0 ?m long×372.0 ?m wide is photographed with a 1000-fold magnification and the photograph is visually observed, a number of pores having a diameter of 0.2 to 0.6 ?m is 250 or less.
    Type: Application
    Filed: October 30, 2017
    Publication date: February 15, 2018
    Applicant: NGK INSULATORS, LTD.
    Inventors: Kiyoshi MATSUSHIMA, Morimichi Watanabe, Kei Sato, Tsutomu Nanataki
  • Patent number: 9893234
    Abstract: Provided is a light emitting device composite substrate suitable for manufacturing large-area light emitting devices at low cost. The light emitting device composite substrate comprises a substrate composed of an oriented polycrystalline alumina sintered body, and a light emitting functional layer formed on the substrate and having two or more layers composed of semiconductor single crystal grains, wherein each of the two or more layers has a single crystal structure in a direction approximately normal to the substrate.
    Type: Grant
    Filed: June 15, 2016
    Date of Patent: February 13, 2018
    Assignee: NGK Insulators, Ltd.
    Inventors: Morimichi Watanabe, Jun Yoshikawa, Tsutomu Nanataki, Katsuhiro Imai, Tomohiko Sugiyama, Takashi Yoshino, Yukihisa Takeuchi, Kei Sato
  • Patent number: 9824869
    Abstract: Provided is a zinc oxide-based sputtering target that enables production of a zinc oxide-based sputtered film having higher transparency and electrical conductivity. The zinc oxide-based sputtering target of the present invention is composed of a zinc oxide-based sintered body including zinc oxide crystal grains as a main phase and spinel phases as a dopant-containing grain boundary phase, and the zinc oxide-based sputtering target has a degree of (002) orientation of ZnO of 80% or greater at a sputtering surface, a density of the zinc oxide-based sintered body of 5.50 g/cm3 or greater, the number of the spinel phases per area of 20 counts/100 ?m2 or greater, and a spinel phase distribution index of 0.40 or less.
    Type: Grant
    Filed: September 9, 2015
    Date of Patent: November 21, 2017
    Assignee: NGK Insulators, Ltd.
    Inventors: Jun Yoshikawa, Hirofumi Yamaguchi, Tsutomu Nanataki
  • Patent number: 9768352
    Abstract: Provided is a self-supporting polycrystalline GaN substrate composed of GaN-based single crystal grains having a specific crystal orientation in a direction approximately normal to the substrate. The crystal orientations of individual GaN-based single crystal grains as determined from inverse pole figure mapping by EBSD analysis on the substrate surface are distributed with tilt angles from the specific crystal orientation, the average tilt angle being 1 to 10°. There is also provided a light emitting device including the self-supporting substrate and a light emitting functional layer, which has at least one layer composed of semiconductor single crystal grains, the at least one layer having a single crystal structure in the direction approximately normal to the substrate. The present invention makes it possible to provide a self-supporting polycrystalline GaN substrate having a reduced defect density at the substrate surface, and to provide a light emitting device having a high luminous efficiency.
    Type: Grant
    Filed: November 23, 2016
    Date of Patent: September 19, 2017
    Assignee: NGK Insulators, Ltd.
    Inventors: Morimichi Watanabe, Jun Yoshikawa, Yoshitaka Kuraoka, Tsutomu Nanataki
  • Patent number: 9767961
    Abstract: The present invention relates to a composite electronic component having a dielectric body portion inside of which a conductive body is provided, and a magnetic body portion inside of which a conductive body is provided. In the present invention, a layer made of a metal material is arranged between the dielectric body portion and the magnetic body portion as an intermediate layer.
    Type: Grant
    Filed: March 13, 2012
    Date of Patent: September 19, 2017
    Assignee: NGK Insulators, Ltd.
    Inventors: Naoto Ohira, Natsumi Shimogawa, Hirofumi Yamaguchi, Tsutomu Nanataki
  • Publication number: 20170174574
    Abstract: An alumina sintered body according to the present invention has a degree of c-plane orientation of 90% or more as determined by Lotgering's method from an X-ray diffraction profile obtained by irradiating a plate surface with X-rays in a range of 2?=20° to 70°. The alumina sintered body has no pores when a cross-sectional surface formed in a direction perpendicular to the plate surface is polished using an Ar+ ion beam and a mask and is examined under a scanning electron microscope at a magnification of 5,000 times. The alumina sintered body has a total mass fraction of impurity elements other than Mg and C of 100 ppm or less. This alumina sintered body has a high degree of orientation, high density, and high purity and thus has a higher optical translucency than those known in the art.
    Type: Application
    Filed: March 2, 2017
    Publication date: June 22, 2017
    Applicant: NGK INSULATORS, LTD.
    Inventors: Kiyoshi MATSUSHIMA, Morimichi WATANABE, Kei SATO, Tsutomu NANATAKI
  • Publication number: 20170174524
    Abstract: A plate-like alumina powder production method of the present invention comprises placing a transition alumina and a fluoride in a container such that the transition alumina and the fluoride do not come into contact with each other and then performing heat treatment to obtain a plate-like ?-alumina powder. The transition alumina is preferably at least one selected from the group consisting of gibbsite, boehmite, and ?-alumina. It is preferable that the amount of the fluoride used is set such that the percentage ration of F in the fluoride to the transition alumina is 0.017% by mass or more. The container preferably has a volume such that a value obtained by dividing the mass of F in the fluoride by the volume of the container is 6.5×10?5 g/cm3 or more. The heat treatment is preferably performed at the temperature of 750 to 1,650° C.
    Type: Application
    Filed: March 1, 2017
    Publication date: June 22, 2017
    Applicant: NGK INSULATORS, LTD.
    Inventors: Hiroshi FUKUI, Kei SATO, Morimichi WATANABE, Tsutomu NANATAKI
  • Publication number: 20170166484
    Abstract: A method for producing a transparent alumina sintered body includes (a) the step of preparing an alumina raw material powder containing a plate-like alumina powder having an aspect ratio of 3 or more so that the mass ratio R1 of F to Al in the alumina raw material powder is 5 ppm or more, and forming a compaction raw material containing the alumina raw material powder into a compact, and (b) the step of pressure-sintering the compact at a temperature at which F evaporate to yield a transparent alumina sintered body.
    Type: Application
    Filed: March 1, 2017
    Publication date: June 15, 2017
    Applicant: NGK INSULATORS, LTD.
    Inventors: Kiyoshi MATSUSHIMA, Morimichi WATANABE, Kei SATO, Tsutomu NANATAKI
  • Publication number: 20170166454
    Abstract: 96 parts by mass of a ?-alumina powder, 4 parts by mass of a an AlF3 powder, and 0.17 parts by mass of an ?-alumina powder as a seed crystal were mixed by a pot mill. The purities of each raw material were evaluated, and it was found that the mass ratio of each impurity element other than Al, O, F, H, C, and S was 10 ppm or less. In a high-purity alumina-made sagger having a purity of 99.9 percent by mass, 300 g of the obtained mixed powder was received, and after a high-purity alumina-made lid having a purity of 99.9 percent by mass was placed on the sagger, a heat treatment was perforated at 900° C. for 3 hours in an electric furnace in an air flow atmosphere, so that an alumina powder was obtained. The value of AlF3 mass/container volume was 0.016 g/cm3.
    Type: Application
    Filed: March 1, 2017
    Publication date: June 15, 2017
    Applicant: NGK INSULATORS, LTD.
    Inventors: Morimichi WATANABE, Hiroshi FUKUI, Kei SATO, Tsutomu NANATAKI
  • Patent number: 9663871
    Abstract: A crystal production method according to the present invention includes a film formation and crystallization step of spraying a raw material powder containing a raw material component to form a film containing the raw material component on a seed substrate containing a single crystal at a predetermined single crystallization temperature at which single crystallization of the raw material component occurs, and crystallizing the film containing the raw material while maintaining the single crystallization temperature. In the film formation and crystallization step, preferably, the single crystallization temperature is 900° C. or higher. Furthermore, in the film formation and crystallization step, preferably, the raw material powder and the seed substrate are each a nitride or an oxide.
    Type: Grant
    Filed: April 19, 2013
    Date of Patent: May 30, 2017
    Assignee: NGK Insulators, Ltd.
    Inventors: Nobuyuki Kobayashi, Kazuki Maeda, Koichi Kondo, Tsutomu Nanataki, Katsuhiro Imai, Jun Yoshikawa
  • Patent number: 9640720
    Abstract: Provided is a surface light-emitting device comprising a substrate composed of an oriented polycrystalline zinc oxide sintered body in a plate shape, a light emitting functional layer provided on the substrate, and an electrode provided on the light emitting functional layer. According to the present invention, a surface light-emitting device having high luminous efficiency can be inexpensively provided.
    Type: Grant
    Filed: June 12, 2015
    Date of Patent: May 2, 2017
    Assignee: NGK Insulators, Ltd.
    Inventors: Morimichi Watanabe, Katsuhiro Imai, Jun Yoshikawa, Tsutomu Nanataki, Takashi Yoshino, Yukihisa Takeuchi
  • Publication number: 20170077349
    Abstract: Provided is a self-supporting polycrystalline GaN substrate composed of GaN-based single crystal grains having a specific crystal orientation in a direction approximately normal to the substrate. The crystal orientations of individual GaN-based single crystal grains as determined from inverse pole figure mapping by EBSD analysis on the substrate surface are distributed with tilt angles from the specific crystal orientation, the average tilt angle being 1 to 10°. There is also provided a light emitting device including the self-supporting substrate and a light emitting functional layer, which has at least one layer composed of semiconductor single crystal grains, the at least one layer having a single crystal structure in the direction approximately normal to the substrate. The present invention makes it possible to provide a self-supporting polycrystalline GaN substrate having a reduced defect density at the substrate surface, and to provide a light emitting device having a high luminous efficiency.
    Type: Application
    Filed: November 23, 2016
    Publication date: March 16, 2017
    Applicant: NGK INSULATORS, LTD.
    Inventors: Morimichi WATANABE, Jun YOSHIKAWA, Yoshitaka KURAOKA, Tsutomu NANATAKI
  • Publication number: 20170053801
    Abstract: There is provided a production method which enables stable formation of a p-type zinc oxide film and also is suitable for enlarging the area of the film. The method for producing a p-type zinc oxide film according to the present invention comprises the steps of: placing a target containing a zinc source and a substrate in a gas atmosphere containing a nitrogen source and an oxygen source and having a gas pressure of 0.1 Pa to 100 Pa, and exposing the target to arc discharge, thereby forming a precursor film containing zinc and oxygen on the substrate; and annealing the precursor film in an oxidizing atmosphere, thereby forming a p-type zinc oxide film.
    Type: Application
    Filed: November 9, 2016
    Publication date: February 23, 2017
    Applicants: NAGOYA INSTITUTE OF TECHNOLOGY, NGK INSULATORS, LTD.
    Inventors: Masaki TANEMURA, Morimichi WATANABE, Jun YOSHIKAWA, Tsutomu NANATAKI
  • Publication number: 20170044022
    Abstract: A method of producing hexagonal plate-like zinc oxide particles having a sharp particle size distribution (i.e., a relatively uniform particle size) at a high weight yield and a high percent yield is provided. The method of producing hexagonal plate-like zinc oxide particles of the present invention comprises mixing by stirring an aqueous hexamethylenetetramine (HMT) solution, a solution of an anionic surfactant in a water-insoluble organic solvent, and optionally water to form a microemulsion containing an aqueous phase of an aqueous hexamethylenetetramine solution having a molar concentration of 0.05 M or more; dropwise adding an aqueous zinc salt solution to the microemulsion; and heating the microemulsion containing the aqueous zinc salt solution to a reaction temperature of 80° C. or more without using any autoclave to form hexagonal plate-like zinc oxide particles.
    Type: Application
    Filed: October 28, 2016
    Publication date: February 16, 2017
    Applicants: NGK INSULATORS, LTD., NAGOYA INSTITUTE OF TECHNOLOGY
    Inventors: Jun YOSHIKAWA, Tsutomu NANATAKI, Tomokatsu HAYAKAWA
  • Patent number: 9548418
    Abstract: Provided is a self-supporting gallium nitride substrate useful as an alternative material for a gallium nitride single crystal substrate, which is inexpensive and also suitable for having a large area. This substrate is composed of a plate composed of gallium nitride-based single crystal grains, wherein the plate has a single crystal structure in the approximately normal direction. This substrate can be manufactured by a method comprising providing an oriented polycrystalline sintered body; forming a seed crystal layer composed of gallium nitride on the sintered body so that the seed crystal layer has crystal orientation mostly in conformity with the crystal orientation of the sintered body; forming a layer with a thickness of 20 ?m or greater composed of gallium nitride-based crystals on the seed crystal layer so that the layer has crystal orientation mostly in conformity with crystal orientation of the seed crystal layer; and removing the sintered body.
    Type: Grant
    Filed: February 5, 2016
    Date of Patent: January 17, 2017
    Assignee: NGK Insulators, Ltd.
    Inventors: Morimichi Watanabe, Jun Yoshikawa, Tsutomu Nanataki, Katsuhiro Imai, Tomohiko Sugiyama, Takashi Yoshino, Yukihisa Takeuchi, Kei Sato
  • Patent number: 9543473
    Abstract: Provided is a self-supporting polycrystalline GaN substrate composed of GaN-based single crystal grains having a specific crystal orientation in a direction approximately normal to the substrate. The crystal orientations of individual GaN-based single crystal grains as determined from inverse pole figure mapping by EBSD analysis on the substrate surface are distributed with tilt angles from the specific crystal orientation, the average tilt angle being 1 to 10°. There is also provided a light emitting device including the self-supporting substrate and a light emitting functional layer, which has at least one layer composed of semiconductor single crystal grains, the at least one layer having a single crystal structure in the direction approximately normal to the substrate. The present invention makes it possible to provide a self-supporting polycrystalline GaN substrate having a reduced defect density at the substrate surface, and to provide a light emitting device having a high luminous efficiency.
    Type: Grant
    Filed: March 17, 2016
    Date of Patent: January 10, 2017
    Assignee: NGK Insulators, Ltd.
    Inventors: Morimichi Watanabe, Jun Yoshikawa, Yoshitaka Kuraoka, Tsutomu Nanataki
  • Patent number: 9543567
    Abstract: The present invention relates to a method for manufacturing cathode active material for a lithium secondary battery. The manufacturing method according to the present invention is characterized by including: (1) an intermediate generation process, wherein an intermediate which is powder or a shaped object containing the first material compound which is a compound of the transition metal other than lithium, which constitutes said lithium composite oxide, is generated, (2) a lithium source compound addition process, wherein the second material compound which is a lithium compound is added so that the second material compound in the shape of film may adhere to the surface of said intermediate, and (3) a sintering process, wherein lithium composite oxide is generated by sintering said intermediate in the state where said second material compound has adhered to its surface.
    Type: Grant
    Filed: September 13, 2012
    Date of Patent: January 10, 2017
    Assignee: NGK Insulators, Ltd.
    Inventors: Naoto Ohira, Ryuta Sugiura, Shohei Yokoyama, Miho Endo, Koji Kimura, Tsutomu Nanataki