Patents by Inventor Tomohiko Ohta

Tomohiko Ohta 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: 20230175166
    Abstract: The present invention is a single-crystal pulling apparatus including: a pulling furnace which has a heater and a crucible arranged and which has a central axis; and a magnetic field generation device having superconducting coils, where the magnetic field generation device has four of the superconducting coils, two of the superconducting coils are arranged in each of two regions divided by a cross section that includes an X axis, the X axis being a direction of lines of magnetic force at the central axis in the horizontal plane including all the coil axes of the four superconducting coils, and includes the central axis of the pulling furnace so as to have line symmetry about the cross section, the four superconducting coils are all arranged so that the coil axes have an angle within a range of more than ?30° and less than 30° relative to a Y axis, the direction of the lines of magnetic force thereof have line symmetry about the cross section, and in each of the regions, the two superconducting coils generate
    Type: Application
    Filed: March 19, 2020
    Publication date: June 8, 2023
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Kiyotaka TAKANO, Wataru YAJIMA, Kosei SUGAWARA, Hiroyuki KAMADA, Tomohiko OHTA
  • Publication number: 20230138632
    Abstract: A single-crystal pulling apparatus including: a pulling furnace having a central axis; and a magnetic field generation device arranged around the pulling furnace and having superconducting coils, the apparatus applying a horizontal magnetic field to the molten semiconductor raw material, two coil axes in the two pairs of the superconducting coils are included in a single horizontal plane, and when a direction of lines of magnetic force at the central axis of the pulling furnace in the horizontal plane is determined as an X axis, a center angle ? having the X axis between the two coil axes is 100 degrees or more and 120 degrees or less. This makes it possible to reduce the height of the coils, to raise the magnetic field center close to the melt surface of the semiconductor raw material, and to obtain a single crystal having a lower oxygen concentration than conventional single crystals.
    Type: Application
    Filed: February 22, 2021
    Publication date: May 4, 2023
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Kiyotaka TAKANO, Kosei SUGAWARA, Hiroyuki KAMADA, Takahide ONAI, Tomohiko OHTA
  • Publication number: 20230047427
    Abstract: A method for producing a silicon single crystal, wherein a silicon nitride powder is introduced into a raw material before start of melting and the silicon single crystal doped with nitrogen is pulled by Czochralski method, wherein nitrogen doping is performed while an upper limit amount of usable silicon nitride powder is limited based on an amount of carbon impurities contained in the silicon nitride powder so that a carbon concentration in the silicon single crystal is equal to or less than allowable value. This makes it possible to achieve the required nitrogen doping amount at low cost while achieving the low carbon-concentration specification.
    Type: Application
    Filed: December 1, 2020
    Publication date: February 16, 2023
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Kosei SUGAWARA, Ryoji HOSHI, Tomohiko OHTA
  • Publication number: 20220120753
    Abstract: The present invention is intended to provide a method for determining the prognosis of a hormone receptor-positive cancer (for example, an ER?-positive breast cancer, an ER?-positive endometrial cancer, etc.) or a method for assisting the determination of the prognosis, and a method for evaluating the sensitivity of the cancer to antihormone therapy or a method for assisting the evaluation of the sensitivity of the cancer to antihormone therapy. Specifically, the present invention relates to a method for determining the prognosis of a hormone receptor-positive cancer, or a method for assisting the determination of the prognosis, which comprises the following steps (a) and (b): (a) a step of detecting Fbxo22-positive cancer cells in a sample derived from the cancer tissues; and (b) a step of calculating the percentage of the Fbxo22-positive cancer cells to the cells present in the sample.
    Type: Application
    Filed: September 20, 2019
    Publication date: April 21, 2022
    Applicants: The University of Tokyo, St. Marianna University School of Medicine
    Inventors: Makoto NAKANISHI, Yoshikazu JOHMURA, Tomohiko OHTA
  • 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: 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: 20100113557
    Abstract: The present invention provides a method for inhibiting a tumor, which comprises suppressing the expression of HERC2. In one embodiment of the present invention, the suppression of HERC2 is induced by the expression of BRCA1.
    Type: Application
    Filed: December 18, 2006
    Publication date: May 6, 2010
    Applicant: St. Marianna University School of Medicine
    Inventors: Tomohiko Ohta, Ko Sato
  • Publication number: 20100041096
    Abstract: The present invention provides a method of polyubiquitinating a nucleophosmin comprised of reacting the nucleophosmin in vitro or in vivo with BRCA1-BARD1. The present invention also provides a method of inhibiting polyubiquitination of nucleophosmin comprised of phosphorylating BARD1 using CDK2-cyclin E and/or CDK2-cyclin A.
    Type: Application
    Filed: May 20, 2009
    Publication date: February 18, 2010
    Inventor: Tomohiko Ohta
  • Patent number: 7625732
    Abstract: The present invention provides isolated polynucleotide sequences encoding the proteins ROC1 and ROC2, the isolated proteins themselves, expression vectors containing at least a fragment of the ROC1 and ROC2 polynucleotide sequences, and host cells comprising the same. Methods of producing the ROC1 and ROC2 proteins are also disclosed, and methods of detecting the polynucleotides in samples are included in this invention, as are antibodies to the ROC1 and ROC2 proteins and antisense molecules complementary to polynucleotides encoding the same. The present invention further includes methods for screening bioactive agents that are capable of binding to a ROC protein, methods of screening bioactive agents capable of interfering with the binding of ROC proteins, and methods of screening bioactive agents capable of modulating the activity of a ROC protein. Such screening methods are capable of identifying compounds that have pharmacological.
    Type: Grant
    Filed: July 10, 2006
    Date of Patent: December 1, 2009
    Assignee: The University of North Carolina at Chapel Hill
    Inventors: Yue Xiong, Tomohiko Ohta
  • Publication number: 20090130760
    Abstract: The present invention provides a method for ubiquitinating RNA polymerases, comprising bringing the RNA polymerases into contact with BRCA1-BARD1.
    Type: Application
    Filed: October 18, 2006
    Publication date: May 21, 2009
    Applicant: ST. MARIANNA UNIVERSITY SCHOOL OF MEDICINE
    Inventors: Tomohiko Ohta, Wenwen Wu
  • Patent number: 7521334
    Abstract: A method for producing a direct bonded wafer comprising: forming a thermal oxide film or a CVD oxide film on a surface of at least one of a bond wafer and a base wafer, and bonding the wafer to the other wafer via the oxide film; subsequently thinning the bond wafer to prepare a bonded wafer; and thereafter conducting a process of annealing the bonded wafer under an atmosphere including any one of an inert gas, hydrogen and a mixed gas of an inert gas and hydrogen so that the oxide film between the bond wafer and the base wafer is removed to bond the bond wafer directly to the base wafer. Thereby, there is provided a method for producing a direct bonded wafer in which generation of voids is reduced, and a direct bonded wafer with a low void count.
    Type: Grant
    Filed: November 29, 2005
    Date of Patent: April 21, 2009
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Norihiro Kobayashi, Toru Ishizuka, Tomohiko Ohta, Hiroji Aga, Yasuo Nagaoka
  • Publication number: 20080274479
    Abstract: The present invention relates to an assay method for determining a auto-ubiquitination activity of synoviolin, comprising reacting synoviolin and ubiquitin in a reaction system containing them and determining an amount of ubiquitin binding to synoviolin, to a method of screening a substance capable of regulating such an activity, and to a kit for auto-ubiquitination assay of synoviolin.
    Type: Application
    Filed: June 2, 2005
    Publication date: November 6, 2008
    Applicant: LOCOMOGENE, INC.
    Inventors: Toshihiro Nakajima, Sayumi Toriyama, Tadayuki Yamadera, Tomohiko Ohta, Satoshi Yamasaki, Naoko Yagishita, Lei Zhang, Rie Ikeda, Takeshi Sasaki, Tetsuya Amano
  • Publication number: 20080102603
    Abstract: A method for producing a direct bonded wafer comprising: forming a thermal oxide film or a CVD oxide film on a surface of at least one of a bond wafer and a base wafer, and bonding the wafer to the other wafer via the oxide film; subsequently thinning the bond wafer to prepare a bonded wafer; and thereafter conducting a process of annealing the bonded wafer under an atmosphere including any one of an inert gas, hydrogen and a mixed gas of an inert gas and hydrogen so that the oxide film between the bond wafer and the base wafer is removed to bond the bond wafer directly to the base wafer. Thereby, there is provided a method for producing a direct bonded wafer in which generation of voids is reduced, and a direct bonded wafer with a low void count.
    Type: Application
    Filed: November 29, 2005
    Publication date: May 1, 2008
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Norihiro Kobayashi, Toru Ishizuka, Tomohiko Ohta, Hiroji Aga, Yasuo Nagaoka
  • Patent number: 7294196
    Abstract: In a method for producing a silicon single crystal by Czochralski method, the single crystal is grown with controlling a growth rate between a growth rate at a boundary where a defect region detected by Cu deposition remaining after disappearance of OSF ring disappears when gradually decreasing a growth rate of silicon single crystal during pulling and a growth rate at a boundary where a high oxygen precipitation Nv region having a density of BMDs of 1×107 numbers/cm3 or more and/or a wafer lifetime of 30 ?sec or less after oxygen precipitation treatment disappears when gradually decreasing the growth rate further. Thereby, there is provided a silicon single crystal which does not belong to any of V region rich in vacancy, OSF region and I region rich in interstitial silicon, and has excellent electrical characteristics and gettering capability, so that yield of devices can be surely improved, and also an epitaxial wafer.
    Type: Grant
    Filed: May 7, 2003
    Date of Patent: November 13, 2007
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Masahiro Sakurada, Nobuaki Mitamura, Izumi Fusegawa, Tomohiko Ohta
  • Patent number: 7226507
    Abstract: The present invention is a method for producing a single crystal of which a whole plane in a radial direction is a defect-free region with pulling the single crystal from a raw material melt in a chamber by Czochralski method, wherein a pulling condition is changed in a direction of the crystal growth axis during pulling the single crystal so that a margin of a pulling rate is always a predetermined value or more that the single crystal of which the whole plane in a radial direction is a defect-free region can be pulled. Thereby, there can be provided a method for producing a single crystal in which when a single crystal is produced by CZ method, the single crystal of which a whole plane in a radial direction is a defect-free region entirely in a direction of the crystal growth axis can be produced with stability.
    Type: Grant
    Filed: May 27, 2004
    Date of Patent: June 5, 2007
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Nobuaki Mitamura, Tomohiko Ohta, Izumi Fusegawa, Masahiro Sakurada, Atsushi Ozaki
  • Publication number: 20070101926
    Abstract: The present invention is a method of manufacturing a silicon single crystal by Czochralski method without performing Dash Necking method, comprising the steps of: providing a seed crystal having a tip end with a sharp-pointed shape or a truncation thereof in which an angle of the tip end is 28° or less; keeping the tip end of the seed crystal at just above a silicon melt to heat it before bringing the tip end of the seed crystal into contact with the silicon melt; bringing the tip end of the seed crystal into contact with the silicon melt and immersing the seed crystal into the silicon melt to a desired diameter; and shifting to pull the single crystal, wherein a temperature variation at a surface of the silicon melt is kept at ±5° C. or less at least for a period from a point of bringing the tip end of the seed crystal into contact with the silicon melt to a point of shifting to pull the single crystal.
    Type: Application
    Filed: January 4, 2007
    Publication date: May 10, 2007
    Applicant: Shin-Etsu Handotai Co., Ltd.
    Inventors: Izumi FUSEGAWA, Sadayuki Okuni, Nobuaki Mitamura, Tomohiko Ohta, Nobuo Katuoka
  • Patent number: 7201801
    Abstract: The present invention provides a heater for manufacturing a crystal by the Czochralski method comprising at least terminal portions supplied with current and a heat generating portion by resistance heating, and being arranged so as to surround a crucible containing a raw material melt, wherein the heater has a uniform heat generation distribution to the raw material melt after deformation while in use during crystal manufacture. It is thus possible to prevent hindrance of monocrystallization and unstable crystal quality caused by ununiform temperature in the raw material melt due to deformation of the shape of the heater's heat generating portion while in use during crystal manufacture.
    Type: Grant
    Filed: September 8, 2003
    Date of Patent: April 10, 2007
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Susumu Sonokawa, Ryoji Hoshi, Wataru Sato, Tomohiko Ohta
  • Patent number: 7179330
    Abstract: The present invention is a method of manufacturing a silicon single crystal by Czochralski method without performing Dash Necking method, wherein a temperature variation at a surface of a silicon melt is kept at ±5° C. or less at least for a period from a point of bringing the tip end of a seed crystal into contact with the silicon melt to a point of shifting to pull the single crystal. Thereby, in a method of growing a silicon single crystal by Czochralski method without using Dash Necking method, a success ratio of growing a single crystal free from dislocation can be increased, at the same time a heavy silicon single crystal having a large diameter in which a diameter of a constant diameter portion is over 200 mm can be grown even in the case of growing a silicon single crystal having a crystal orientation of <110>.
    Type: Grant
    Filed: April 23, 2003
    Date of Patent: February 20, 2007
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Izumi Fusegawa, Sadayuki Okuni, Nobuaki Mitamura, Tomohiko Ohta, Nobuo Katuoka
  • Publication number: 20060252098
    Abstract: The present invention provides isolated polynucleotide sequences encoding the proteins ROC1 and ROC2, the isolated proteins themselves, expression vectors containing at least a fragment of the ROC1 and ROC2 polynucleotide sequences, and host cells comprising the same. Methods of producing the ROC1 and ROC2 proteins are also disclosed, and methods of detecting the polynucleotides in samples are included in this invention, as are antibodies to the ROC1 and ROC2 proteins and antisense molecules complementary to polynucleotides encoding the same. The present invention further includes methods for screening bioactive agents that are capable of binding to a ROC protein, methods of screening bioactive agents capable of interfering with the binding of ROC proteins, and methods of screening bioactive agents capable of modulating the activity of a ROC protein. Such screening methods are capable of identifying compounds that have pharmacological.
    Type: Application
    Filed: July 10, 2006
    Publication date: November 9, 2006
    Inventors: Yue Xiong, Tomohiko Ohta
  • Patent number: 7129123
    Abstract: In a method for producing an SOI wafer comprising steps of implanting ions from a bond wafer surface to form an ion-implanted layer inside the wafer, bonding the ion-implanted bond wafer surface and a surface of a base wafer via an oxide film or directly, and forming an SOI wafer by delaminating by heat treatment a part of the bond wafer at the ion-implanted layer, the bond wafer is a silicon wafer that consists of a silicon single crystal grown by Czochralski method, that is occupied by N region outside OSF generated in a ring shape and that has no defect region detected by Cu deposition method. Thereby, even an extremely thin SOI layer having a thickness of 200 nm or less, can provide an SOI wafer that has an excellent electric property without micro pits caused by acid cleaning, and can be produced without increasing the number of processes.
    Type: Grant
    Filed: October 24, 2003
    Date of Patent: October 31, 2006
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Masahiro Sakurada, Nobuaki Mitamura, Izumi Fusegawa, Tomohiko Ohta