Patents by Inventor Nobuaki Mitamura

Nobuaki Mitamura 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: 20240003046
    Abstract: A single crystal manufacturing including: main chamber; pulling chamber; thermal shield member provided so as to face a silicon melt; rectifying cylinder provided on the thermal shield member so as to enclose the silicon single crystal being pulled up; cooling cylinder provided so as to encircle the silicon single crystal being pulled up and including an extending portion extending toward the silicon melt; and cooling auxiliary cylinder fitted to inside of the cooling cylinder. The extending portion of the cooling cylinder includes a bottom surface facing the silicon melt. The cooling auxiliary cylinder includes at least a first portion surrounding the bottom surface of the cooling cylinder and a second portion surrounding an upper end portion of the rectifying cylinder. This enables provision of the apparatus capable of manufacturing a single crystal with a carbon concentration lower than that according to the conventional technologies.
    Type: Application
    Filed: November 1, 2021
    Publication date: January 4, 2024
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Keisuke MIHARA, Kazuya YANASE, Nobuaki MITAMURA, Kiyotaka TAKANO
  • Patent number: 11709384
    Abstract: A multilayer film includes a single-crystal silicon layer, a first layer containing Zr, a second layer containing ZrO2, and a third layer containing a perovskite oxide having an electrooptic effect. The first layer, the second layer, and the third layer are provided in this order above the single-crystal silicon layer, and the multilayer film is transparent to a wavelength to be used.
    Type: Grant
    Filed: May 27, 2021
    Date of Patent: July 25, 2023
    Assignee: FUJITSU OPTICAL COMPONENTS LIMITED
    Inventor: Nobuaki Mitamura
  • Publication number: 20230161184
    Abstract: An optical device includes a substrate, a first cladding layer that is laminated on one surface of the substrate, and a first optical waveguide that is formed in the first cladding layer at a side opposite to the substrate in the first cladding layer. The optical device further includes an electro-optic crystal layer that is laminated on a surface of the first cladding layer at a side opposite to the substrate, and a second optical waveguide that is formed of the electro-optic crystal layer on a surface of the electro-optic crystal layer at a side opposite to the first cladding layer. The optical device further includes a second cladding layer that is laminated on a surface of the electro-optic crystal layer at a side opposite to the first cladding layer.
    Type: Application
    Filed: September 19, 2022
    Publication date: May 25, 2023
    Applicant: FUJITSU OPTICAL COMPONENTS LIMITED
    Inventors: Shuntaro MAKINO, Teruo KURAHASHI, Yoshinobu KUBOTA, Yoshihiko YOSHIDA, Nobuaki MITAMURA, Takehito TANAKA
  • Publication number: 20220373828
    Abstract: An optical device includes a silicon substrate, a waveguide formed of a thin film that is laminated on the silicon substrate and that is made of a perovskite oxide with a large electro-optic effect as compared to lithium niobate, and a cladding layer that covers the waveguide. Further, the optical device includes ground electrode that has a ground potential and a signal electrode that is arranged at a position facing the ground electrode and that applies driving voltage to the waveguide.
    Type: Application
    Filed: March 21, 2022
    Publication date: November 24, 2022
    Applicant: Fujitsu Optical Components Limited
    Inventors: YOSHIHIKO YOSHIDA, NOBUAKI MITAMURA, Shuntaro Makino, Yoshinobu Kubota
  • Patent number: 11442298
    Abstract: An optical modulation device includes a substrate, a slot waveguide formed by arranging a pair of electrodes in a groove formed on one side of the substrate and by filling the groove with an electro-optical material, a dielectric film that covers a surface of the electro-optic material filled in the slot waveguide, and a plate member that covers the slot waveguide and is bonded to the dielectric film with an adhesive resin.
    Type: Grant
    Filed: July 31, 2020
    Date of Patent: September 13, 2022
    Assignee: FUJITSU OPTICAL COMPONENTS LIMITED
    Inventor: Nobuaki Mitamura
  • Publication number: 20220004032
    Abstract: A multilayer film includes a single-crystal silicon layer, a first layer containing Zr, a second layer containing ZrO2, and a third layer containing a perovskite oxide having an electrooptic effect. The first layer, the second layer, and the third layer are provided in this order above the single-crystal silicon layer, and the multilayer film is transparent to a wavelength to be used.
    Type: Application
    Filed: May 27, 2021
    Publication date: January 6, 2022
    Applicant: Fujitsu Optical Components Limited
    Inventor: NOBUAKI MITAMURA
  • Publication number: 20210072569
    Abstract: An optical modulation device includes a substrate, a slot waveguide formed by arranging a pair of electrodes in a groove formed on one side of the substrate and by filling the groove with an electro-optical material, a dielectric film that covers a surface of the electro-optic material filled in the slot waveguide, and a plate member that covers the slot waveguide and is bonded to the dielectric film with an adhesive resin.
    Type: Application
    Filed: July 31, 2020
    Publication date: March 11, 2021
    Applicant: Fujitsu Optical Components Limited
    Inventor: NOBUAKI MITAMURA
  • Patent number: 9952441
    Abstract: The filter transmits a light beam of a second wavelength emitted from each of a plurality of second light sources, reflects other light beams incident from a direction intersecting a traveling direction of the light beam of the second wavelength, and outputs a combined light of the light beam of the second wavelength and the other light beams. The first optical element transmits part of the light beam of the first wavelength emitted from the first light source or part of the light beam of the second wavelength included in the combined light output from the filter, and reflects the other light beams excluding the part thereof in the direction intersecting the traveling direction. The first light receiving element receives the part of the light beam of the first wavelength transmitted by the first optical element or the part of the light beam of the second wavelength.
    Type: Grant
    Filed: November 22, 2016
    Date of Patent: April 24, 2018
    Assignee: FUJITSU OPTICAL COMPONENTS LIMITED
    Inventor: Nobuaki Mitamura
  • Patent number: 9777394
    Abstract: A method of producing silicon single crystal ingot by pulling the silicon single crystal ingot made of an N-region by the CZ method, including: performing an EOSF inspection including a heat treatment to manifest oxide precipitates and selective etching on sample wafer from the silicon single crystal ingot composed of the N-region to measure a density of EOSF; performing a shallow-pit inspection to investigate a pattern of occurrence of a shallow pit; adjusting the pulling conditions according to result of identification of a defect region of the sample wafer by the EOSF and shallow-pit inspections to pull a next silicon single crystal ingot composed of the N-region, wherein in the identification of the defect region, for an N-region, what portion of an Nv-region or Ni-region the defect region corresponds to is also identified.
    Type: Grant
    Filed: January 31, 2014
    Date of Patent: October 3, 2017
    Assignee: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Susumu Sonokawa, Wataru Sato, Nobuaki Mitamura, Tomohiko Ohta
  • Publication number: 20170153458
    Abstract: The filter transmits a light beam of a second wavelength emitted from each of a plurality of second light sources, reflects other light beams incident from a direction intersecting a traveling direction of the light beam of the second wavelength, and outputs a combined light of the light beam of the second wavelength and the other light beams. The first optical element transmits part of the light beam of the first wavelength emitted from the first light source or part of the light beam of the second wavelength included in the combined light output from the filter, and reflects the other light beams excluding the part thereof in the direction intersecting the traveling direction. The first light receiving element receives the part of the light beam of the first wavelength transmitted by the first optical element or the part of the light beam of the second wavelength.
    Type: Application
    Filed: November 22, 2016
    Publication date: June 1, 2017
    Applicant: Fujitsu Optical Components Limited
    Inventor: NOBUAKI MITAMURA
  • Patent number: 9476142
    Abstract: The present invention provides a method for manufacturing a silicon single crystal according to a Czochralski method: bringing a sharp end of a seed crystal into contact with a silicon melt; melting the seed crystal from the end up to a position at which the seed crystal has a predetermined diameter; growing the silicon single crystal without a Dash-Necking process, wherein the seed crystal is melted while a crucible is rotated at a rotational speed of 2 rpm or less, and the rotational speed of the crucible is decelerated to below the rotational speed at the time of the melting within 10 minutes after an end of the melting and a start of the crystal growth. The method avoids reduction in success rate for dislocation-free single crystal growth in manufacture of a heavy, large-diameter ingot and improves the productivity by the dislocation-free seeding method without the necking process.
    Type: Grant
    Filed: November 20, 2012
    Date of Patent: October 25, 2016
    Assignee: SHIN-ETSU HANDOTAI CO., LTD.
    Inventor: Nobuaki Mitamura
  • Patent number: 9234296
    Abstract: The present invention is a semiconductor single crystal manufacturing apparatus including, within a growth furnace main body, a crucible, and a heater disposed around the crucible, wherein a heat insulating cylinder is disposed around the heater within the growth furnace main body, the heat insulating cylinder includes a step portion dividing the heat insulating cylinder into the upper part and the lower part at the inside surface thereof, the inner diameter of the lower part is larger than the inner diameter of the upper part, a heat insulating plate is disposed below the heater and on the inside of the lower part of the heat insulating cylinder within the growth furnace main body, and the diameter of the heat insulating plate is larger than the inner diameter of the upper part of the heat insulating cylinder and is smaller than the inner diameter of the lower part.
    Type: Grant
    Filed: July 6, 2011
    Date of Patent: January 12, 2016
    Assignee: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Shou Takashima, Yuuichi Miyahara, Atsushi Iwasaki, Nobuaki Mitamura, Susumu Sonokawa
  • Publication number: 20150354089
    Abstract: A method of producing silicon single crystal ingot by pulling the silicon single crystal ingot made of an N-region by the CZ method, including: performing an EOSF inspection including a heat treatment to manifest oxide precipitates and selective etching on sample wafer from the silicon single crystal ingot composed of the N-region to measure a density of EOSF; performing a shallow-pit inspection to investigate a pattern of occurrence of a shallow pit; adjusting the pulling conditions according to result of identification of a defect region of the sample wafer by the EOSF and shallow-pit inspections to pull a next silicon single crystal ingot composed of the N-region, wherein in the identification of the defect region, for an N-region, what portion of an Nv-region or Ni-region the defect region corresponds to is also identified.
    Type: Application
    Filed: January 31, 2014
    Publication date: December 10, 2015
    Inventors: Susumu SONOKAWA, Wataru SATO, Nobuaki MITAMURA, Tomohiko OHTA
  • Publication number: 20140326174
    Abstract: The present invention provides a method for manufacturing a silicon single crystal according to a Czochralski method: bringing a sharp end of a seed crystal into contact with a silicon melt; melting the seed crystal from the end up to a position at which the seed crystal has a predetermined diameter; growing the silicon single crystal without a Dash-Necking process, wherein the seed crystal is melted while a crucible is rotated at a rotational speed of 2 rpm or less, and the rotational speed of the crucible is decelerated to below the rotational speed at the time of the melting within 10 minutes after an end of the melting and a start of the crystal growth. The method avoids reduction in success rate for dislocation-free single crystal growth in manufacture of a heavy, large-diameter ingot and improves the productivity by the dislocation-free seeding method without the necking process.
    Type: Application
    Filed: November 20, 2012
    Publication date: November 6, 2014
    Inventor: Nobuaki Mitamura
  • Publication number: 20130340671
    Abstract: A method for manufacturing a silica glass crucible, includes: preparing a crucible base material that is made of silica glass and has a crucible shape; fabricating a synthetic silica glass material based on a direct method or a soot method; processing the synthetic silica glass material into the crucible shape without being pulverized; and bonding an inner wall of the crucible base material and an outer wall of the synthetic silica glass material processed into the crucible shape through a silica powder by performing a heat treatment. As a result, it is possible to provide the silica glass crucible that can avoid occurrence of dislocations of silicon single crystal at the time of manufacturing the silicon single crystal, has high heat-resisting properties, and can suppress a reduction in productivity and yield ratio, the manufacturing method thereof, and the method for manufacturing silicon single crystal using such a silica glass crucible.
    Type: Application
    Filed: February 15, 2012
    Publication date: December 26, 2013
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Akihiro Kimura, Ryoji Hoshi, Nobuaki Mitamura, Hiroyuki Kamada
  • Patent number: 8593138
    Abstract: A bearing residual life prediction method, a bearing residual life diagnostic apparatus and a bearing diagnostic system can be provided. The bearing diagnostic system 20 includes: an eddy current tester 11 that measures the impedance X of a certain portion of a bearing 24 before and after the use of the bearing; a bearing information transmitter 30 that transmits bearing information s1 containing the impedance X; and a bearing information receiver 31 that receives the information; a diagnostic section 12 that obtains the residual life information s2 of the bearing 24 based on the received impedance X; and a life information transmitter 36 that transmits the residual life information s2; and a life information receiver 40 that receives the information. Hence, the bearing used by the user can be inspected nondestructively, and the residual life of the bearing can be predicted.
    Type: Grant
    Filed: December 16, 2010
    Date of Patent: November 26, 2013
    Assignee: NSK Ltd.
    Inventors: Tsuyoshi Nomura, Takamasa Ohira, Nobuaki Mitamura, Masahide Natori, Tohru Ueda, Ichiro Joko, Hidenobu Magami
  • Publication number: 20130125810
    Abstract: The present invention is a semiconductor single crystal manufacturing apparatus including, within a growth furnace main body, a crucible, and a heater disposed around the crucible, wherein a heat insulating cylinder is disposed around the heater within the growth furnace main body, the heat insulating cylinder includes a step portion dividing the heat insulating cylinder into the upper part and the lower part at the inside surface thereof, the inner diameter of the lower part is larger than the inner diameter of the upper part, a heat insulating plate is disposed below the heater and on the inside of the lower part of the heat insulating cylinder within the growth furnace main body, and the diameter of the heat insulating plate is larger than the inner diameter of the upper part of the heat insulating cylinder and is smaller than the inner diameter of the lower part.
    Type: Application
    Filed: July 6, 2011
    Publication date: May 23, 2013
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Shou Takashima, Yuuichi Miyahara, Atsushi Iwasaki, Nobuaki Mitamura, Susumu Sonokawa
  • Patent number: 8088230
    Abstract: A rolling apparatus including an external member having a raceway surface on an inner peripheral surface thereof, an internal member having a raceway surface on an outer peripheral surface thereof, and a plurality of rolling elements which are rotatably provided between the raceway surface of the external member and the raceway surface of the internal member. A surface of at least one of the internal member, the external member, and the rolling elements is subjected to carbonitriding or nitriding; an area percentage of a nitride containing Si and Mn is 1% or more and 20% or less; surface hardness is HV750 or more. When depth from the raceway surface or depth from a rolling surface of the rolling element is defined as Z and diameter of the rolling element is defined as d, hardness at Z=0.045 d is HV650 to 850, and hardness at Z=0.18 d is HV400 to 800.
    Type: Grant
    Filed: May 16, 2007
    Date of Patent: January 3, 2012
    Assignee: NSK Ltd.
    Inventors: Koji Ueda, Toru Ueda, Naoya Seno, Nobuaki Mitamura
  • Publication number: 20110299559
    Abstract: When environmental temperature becomes low, the quantity of light of the backward output light irradiated onto a light absorber formed on a mount over which a chip is mounted, is increased by a light quantity adjuster, to increase the optical absorption by the light absorber, thereby raising its temperature. As a result, the temperature of the chip on the mount rises, thereby enabling to substantially narrow a temperature range on a low temperature side. Accordingly, an optical device with low power consumption that can satisfy characteristics required for signal transmission at a required rate over a wide temperature range can be provided.
    Type: Application
    Filed: February 28, 2011
    Publication date: December 8, 2011
    Applicant: FUJITSU OPTICAL COMPONENTS LIMITED
    Inventor: Nobuaki Mitamura
  • Patent number: RE48336
    Abstract: A rolling apparatus including an external member having a raceway surface on an inner peripheral surface thereof, an internal member having a raceway surface on an outer peripheral surface thereof, and a plurality of rolling elements which are rotatably provided between the raceway surface of the external member and the raceway surface of the internal member. A surface of at least one of the internal member, the external member, and the rolling elements is subjected to carbonitriding or nitriding; an area percentage of a nitride containing Si and Mn is 1% or more and 20% or less; surface hardness is HV750 or more. When depth from the raceway surface or depth from a rolling surface of the rolling element is defined as Z and diameter of the rolling element is defined as d, hardness at Z=0.045 d is HV650 to 850, and hardness at Z=0.18 d is HV400 to 800.
    Type: Grant
    Filed: April 30, 2019
    Date of Patent: December 1, 2020
    Assignee: NSK LTD.
    Inventors: Koji Ueda, Toru Ueda, Naoya Seno, Nobuaki Mitamura