Patents by Inventor Morimichi Watanabe

Morimichi Watanabe 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: 20200216364
    Abstract: An oriented ceramic sintered body production method includes (a) a step of preparing a ceramic compact before firing into an oriented ceramic sintered body; and (b) a step of obtaining an oriented ceramic sintered body by sandwiching the ceramic compact between a pair of releasing sheets, placing the ceramic compact and the releasing sheets in a hot press firing furnace, and hot press firing the ceramic compact while applying a pressure by a pair of punches through the pair of releasing sheets, wherein each of the releasing sheets is a releasing sheet such that, after the releasing sheet is sandwiched between PET films, is then placed and vacuum-packed on a stainless steel sheet, and is isostatically pressed at 200 kg/cm2, a surface of the releasing sheet on the side opposite from the stainless steel sheet has a profile curve with a maximum profile height Pt of 0.8 ?m or less.
    Type: Application
    Filed: March 13, 2020
    Publication date: July 9, 2020
    Applicant: NGK INSULATORS, LTD.
    Inventors: Morimichi WATANABE, Kei SATO, Kiyoshi MATSUSHIMA, Takahiro MAEDA, Jun YOSHIKAWA, Tsutomu NANATAKI
  • Patent number: 10707373
    Abstract: There is provided a self-supporting polycrystalline gallium nitride substrate having excellent characteristics such as high luminous efficiency and high conversion efficiency when used for devices, such as light emitting devices and solar cells. The self-supporting polycrystalline gallium nitride substrate is composed of gallium nitride-based single crystal grains having a specific crystal orientation in a direction approximately normal to the substrate, and has a top surface and a bottom surface. The crystal orientations of individual gallium nitride-based single crystal grains as determined from inverse pole figure mapping by electron backscatter diffraction (EBSD) analysis on the top surface are distributed at various tilt angles from the specific crystal orientation, in which the average tilt angle thereof is 0.1° or more and less than 1° and the cross-sectional average diameter DT of the gallium nitride-based single crystal grains at the outermost surface exposed on the top surface is 10 ?m or more.
    Type: Grant
    Filed: August 9, 2018
    Date of Patent: July 7, 2020
    Assignee: NGK Insulators, Ltd.
    Inventors: Morimichi Watanabe, Kei Sato, Yoshitaka Kuraoka, Katsuhiro Imai, Tsutomu Nanataki
  • Patent number: 10460970
    Abstract: An electrostatic chuck includes a dielectric layer including an oriented alumina sintered body 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 by the irradiation of an X-ray in the 2? range of 20° to 70°; a ceramic layer integrated with a surface disposed opposite a wafer placement surface of the dielectric layer; and an electrostatic electrode between the dielectric layer and the ceramic layer.
    Type: Grant
    Filed: February 23, 2018
    Date of Patent: October 29, 2019
    Assignee: NGK Insulators, Ltd.
    Inventors: Morimichi Watanabe, Tsutomu Nanataki
  • Patent number: 10435815
    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: Grant
    Filed: February 22, 2018
    Date of Patent: October 8, 2019
    Assignee: NGK Insulators, Ltd.
    Inventors: Morimichi Watanabe, Kei Sato, Kiyoshi Matsushima, Tsutomu Nanataki
  • Patent number: 10435816
    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: Grant
    Filed: February 22, 2018
    Date of Patent: October 8, 2019
    Assignee: NGK Insulators, Ltd.
    Inventors: Morimichi Watanabe, Kei Sato, Kiyoshi Matsushima, Tsutomu Nanataki
  • Patent number: 10427949
    Abstract: An alumina sintered body of the present invention has a degree of c-plane orientation of 5% or more, which is determined by a Lotgering method using an X-ray diffraction profile in a range of 2?=20° to 70° obtained under X-ray irradiation, and an XRC half width of 15.0° or less in rocking curve measurement, an F content of less than 0.99 mass ppm when measured by D-SIMS, a crystal grain diameter of 15 to 200 ?m, and 25 or less pores having a diameter of 0.2 ?m to 1.0 ?m when a photograph of a viewing area 370.0 ?m in a vertical direction and 372.0 ?m in a horizontal direction taken at a magnification factor of 1000 is visually observed.
    Type: Grant
    Filed: March 1, 2018
    Date of Patent: October 1, 2019
    Assignee: NGK Insulators, Ltd.
    Inventors: Kiyoshi Matsushima, Morimichi Watanabe, Kei Sato, Tsutomu Nanataki
  • Patent number: 10343928
    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: Grant
    Filed: March 1, 2017
    Date of Patent: July 9, 2019
    Assignee: NGK Insulators, Ltd.
    Inventors: Morimichi Watanabe, Hiroshi Fukui, Kei Sato, Tsutomu Nanataki
  • Patent number: 10336625
    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: Grant
    Filed: October 30, 2017
    Date of Patent: July 2, 2019
    Assignee: NGK Insulators, Ltd.
    Inventors: Kiyoshi Matsushima, Morimichi Watanabe, Kei Sato, Tsutomu Nanataki
  • Patent number: 10315957
    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: Grant
    Filed: March 1, 2017
    Date of Patent: June 11, 2019
    Assignee: NGK Insulators, Ltd.
    Inventors: Kiyoshi Matsushima, Morimichi Watanabe, Kei Sato, Tsutomu Nanataki
  • Patent number: 10221076
    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 0.17% 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: Grant
    Filed: March 1, 2017
    Date of Patent: March 5, 2019
    Assignee: NGK Insulators, Ltd.
    Inventors: Hiroshi Fukui, Kei Sato, Morimichi Watanabe, Tsutomu Nanataki
  • Patent number: 10156024
    Abstract: Disclosed is a self-supporting zinc oxide substrate composed of a plate composed of a plurality of zinc-oxide-based single crystal grains, wherein the plate has a single crystal structure in an approximately normal direction, and the zinc-oxide-based single crystal grains have a cross-sectional average diameter of greater than 1 ?m. This substrate can be manufactured by a method comprising providing an oriented polycrystalline sintered body; forming a layer with a thickness of 20 ?m or greater composed of zinc-oxide-based crystals on the oriented polycrystalline sintered body so that the layer has crystal orientation mostly in conformity with crystal orientation of the oriented polycrystalline sintered body; and removing the oriented polycrystalline sintered body to obtain the self-supporting zinc oxide substrate.
    Type: Grant
    Filed: November 25, 2015
    Date of Patent: December 18, 2018
    Assignee: NGK Insulators, Ltd.
    Inventors: Morimichi Watanabe, Jun Yoshikawa, Hirofumi Yamaguchi, Tsutomu Nanataki
  • Publication number: 20180351038
    Abstract: There is provided a self-supporting polycrystalline gallium nitride substrate having excellent characteristics such as high luminous efficiency and high conversion efficiency when used for devices, such as light emitting devices and solar cells. The self-supporting polycrystalline gallium nitride substrate is composed of gallium nitride-based single crystal grains having a specific crystal orientation in a direction approximately normal to the substrate, and has a top surface and a bottom surface. The crystal orientations of individual gallium nitride-based single crystal grains as determined from inverse pole figure mapping by electron backscatter diffraction (EBSD) analysis on the top surface are distributed at various tilt angles from the specific crystal orientation, in which the average tilt angle thereof is 0.1° or more and less than 1° and the cross-sectional average diameter DT of the gallium nitride-based single crystal grains at the outermost surface exposed on the top surface is 10 ?m or more.
    Type: Application
    Filed: August 9, 2018
    Publication date: December 6, 2018
    Applicant: NGK INSULATORS, LTD.
    Inventors: Morimichi WATANABE, Kei Sato, Yoshitaka Kuraoka, Katsuhiro Imai, Tsutomu Nanataki
  • Patent number: 10138166
    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: Grant
    Filed: March 2, 2017
    Date of Patent: November 27, 2018
    Assignee: NGK Insulators, Ltd.
    Inventors: Kiyoshi Matsushima, Morimichi Watanabe, Kei Sato, Tsutomu Nanataki
  • Publication number: 20180244579
    Abstract: A method for producing a transparent alumina sintered body according to the present invention includes (a) a step of preparing an alumina raw material powder containing a plate-like alumina powder having an aspect ratio of 3 or more and a fine alumina powder having an average particle diameter smaller than that of the plate-like alumina powder so that, when a mixing ratio of the plate-like alumina powder to the fine alumina powder in terms of mass ratio is assumed to be T:(100?T), T is 0.001 or more and less than 1, and so that a mass ratio R1 of F relative to A1 in the alumina raw material powder is less than 15 ppm; (b) a step of forming a raw material for forming containing the alumina raw material powder into a compact; and (c) a step of sintering the compact so as to obtain a transparent alumina sintered body.
    Type: Application
    Filed: February 23, 2018
    Publication date: August 30, 2018
    Applicant: NGK INSULATORS, LTD.
    Inventors: Morimichi WATANABE, Kiyoshi MATSUSHIMA, Kei SATO, Tsutomu NANATAKI
  • Publication number: 20180237343
    Abstract: A method for producing an oriented sintered body according to the present invention includes the steps of: (a) preparing a multilayer body, the multilayer body including a layer including a fine raw-material powder and a layer including a plate-like raw-material powder which are alternately stacked each other, particles of the plate-like raw-material powder being arranged such that surfaces of the particles of the plate-like raw-material powder extend along a surface of the layer including a fine raw-material powder; and (b) sintering the multilayer body.
    Type: Application
    Filed: April 19, 2018
    Publication date: August 23, 2018
    Applicant: NGK INSULATORS, LTD.
    Inventors: Kei SATO, Takahiro MAEDA, Morimichi WATANABE, Tsutomu NANATAKI
  • Publication number: 20180230020
    Abstract: An alumina sintered body of the present invention has a degree of c-plane orientation of 5% or more, which is determined by a Lotgering method using an X-ray diffraction profile in a range of 2?=20° to 70° obtained under X-ray irradiation, and an XRC half width of 15.0° or less in rocking curve measurement, an F content of less than 0.99 mass ppm when measured by D-SIMS, a crystal grain diameter of 15 to 200 ?m, and 25 or less pores having a diameter of 0.2 ?m to 1.0 ?m when a photograph of a viewing area 370.0 ?m in a vertical direction and 372.0 ?m in a horizontal direction taken at a magnification factor of 1000 is visually observed.
    Type: Application
    Filed: March 1, 2018
    Publication date: August 16, 2018
    Applicant: NGK INSULATORS, LTD.
    Inventors: Kiyoshi MATSUSHIMA, Morimichi Watanabe, Kei Sato, Tsutomu Nanataki
  • Publication number: 20180190527
    Abstract: An electrostatic chuck includes a dielectric layer including an oriented alumina sintered body 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 by the irradiation of an X-ray in the 2? range of 20° to 70°; a ceramic layer integrated with a surface disposed opposite a wafer placement surface of the dielectric layer; and an electrostatic electrode between the dielectric layer and the ceramic layer.
    Type: Application
    Filed: February 23, 2018
    Publication date: July 5, 2018
    Applicant: NGK INSULATORS, LTD.
    Inventors: Morimichi WATANABE, Tsutomu NANATAKI
  • 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