Patents by Inventor Isaho Kamata

Isaho Kamata 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: 20220146564
    Abstract: A semiconductor wafer evaluation apparatus brings a contact maker (mercury liquefied at room temperature), as a Schottky electrode, into contact with a semiconductor wafer, intermittently applies a voltage from a pulse power supply, and evaluates the state (kinds, density) of point defects by an evaluation means based on the status of the electrostatic capacity of the semiconductor wafer. In this manner, the state (kinds, density) of the point defects in the plane of a large-diameter semiconductor wafer is directly evaluated using a large table.
    Type: Application
    Filed: November 5, 2021
    Publication date: May 12, 2022
    Applicant: SHOWA DENKO K.K.
    Inventors: Koichi Murata, Isaho KAMATA, Hidekazu TSUCHIDA, Akira MIYASAKA
  • Publication number: 20220112623
    Abstract: A method and an apparatus for manufacturing a silicon carbide single crystal, and a silicon carbide single crystal ingot, obtaining a silicon carbide single crystal reduced in defects such as threading dislocations, are provided. The method manufactures a silicon carbide single crystal by supplying a raw material gas into a reaction vessel with a seed substrate, and heats the interior to grow a silicon carbide single crystal on the surface of the seed substrate. The method includes growing the silicon carbide single crystal on the seed substrate surface, while controlling the temperature, to perform pair annihilation of threading dislocations or synthesis of the threading dislocations; and a second step of maintaining the temperature inside the reaction vessel in the state of the first predetermined temperature after execution of the first step, to bring the leading ends of the threading dislocations close to the surface of the seed substrate.
    Type: Application
    Filed: October 12, 2021
    Publication date: April 14, 2022
    Inventors: Norihiro HOSHINO, Isaho KAMATA, Hidekazu TSUCHIDA, Takahiro KANDA, Takeshi OKAMOTO
  • Patent number: 11107892
    Abstract: A method for producing a SiC epitaxial wafer according to the present embodiment includes: an epitaxial growth step of growing the epitaxial layer on the SiC single crystal substrate by feeding an Si-based raw material gas, a C-based raw material gas, and a gas including a Cl element to a surface of a SiC single crystal substrate, in which the epitaxial growth step is performed under growth conditions that a film deposition pressure is 30 torr or less, a Cl/Si ratio is in a range of 8 to 12, a C/Si ratio is in a range of 0.8 to 1.2, and a growth rate is 50 ?m/h or more from an initial growth stage.
    Type: Grant
    Filed: April 19, 2018
    Date of Patent: August 31, 2021
    Assignees: SHOWA DENKO K.K., Central Research Institute Of Electric Power Industry, DENSO CORPORATION
    Inventors: Keisuke Fukada, Naoto Ishibashi, Akira Bando, Masahiko Ito, Isaho Kamata, Hidekazu Tsuchida, Kazukuni Hara, Masami Naito, Hideyuki Uehigashi, Hiroaki Fujibayashi, Hirofumi Aoki, Toshikazu Sugiura, Katsumi Suzuki
  • Publication number: 20210108334
    Abstract: In a silicon carbide single crystal wafer, a dislocation density contained therein is 3500 dislocations/cm2 or less, and a difference of the dislocation density among a wafer central part, a wafer peripheral part and a wafer intermediate part is less than 50% of an average value thereof.
    Type: Application
    Filed: September 22, 2020
    Publication date: April 15, 2021
    Inventors: Isaho KAMATA, Hidekazu TSUCHIDA, Norihiro HOSHINO, Yuichiro TOKUDA, Takeshi OKAMOTO
  • Publication number: 20210102311
    Abstract: A silicon carbide single crystal contains a heavy metal element having a specific gravity higher than a specific gravity of iron. An addition density of the heavy metal element at least in an outer peripheral portion of the silicon carbide single crystal is set to 1×1015 cm?3 or more.
    Type: Application
    Filed: December 16, 2020
    Publication date: April 8, 2021
    Inventors: Yuichiro TOKUDA, Hideyuki UEHIGASHI, Norihiro HOSHINO, Hidekazu TSUCHIDA, Isaho KAMATA
  • Patent number: 10896831
    Abstract: A supply part includes a first partition, a second partition under the first partition, a third partition under the second partition, a first flow path between the first partition and the second partition allowing a first gas to be introduced therein, a second flow path between the second partition and the third partition allowing a second gas to be introduced therein, a first piping extending from the second partition to reach below the third partition and being communicated with the first flow path, a second piping extending from the third partition to reach below the third partition and being communicated with the second flow path, and a convex portion provided on an outer circumferential surface of the first piping or an inner circumferential surface of the second piping protruding from one of the outer circumferential surface and the inner circumferential surface toward the other one.
    Type: Grant
    Filed: August 31, 2018
    Date of Patent: January 19, 2021
    Assignees: NuFlare Technology, Inc., Showa Denko K.K., Central Research Institute of Electric Power Industry
    Inventors: Kunihiko Suzuki, Naohisa Ikeya, Keisuke Fukada, Masahiko Ito, Isaho Kamata, Hidekazu Tsuchida, Hiroaki Fujibayashi, Hideyuki Uehigashi, Masami Naito, Kazukuni Hara, Hirofumi Aoki, Takahiro Kozawa
  • Publication number: 20200083330
    Abstract: A method for producing a SiC epitaxial wafer according to the present embodiment includes: an epitaxial growth step of growing the epitaxial layer on the SiC single crystal substrate by feeding an Si-based raw material gas, a C-based raw material gas, and a gas including a Cl element to a surface of a SiC single crystal substrate, in which the epitaxial growth step is performed under growth conditions that a film deposition pressure is 30 torr or less, a Cl/Si ratio is in a range of 8 to 12, a C/Si ratio is in a range of 0.8 to 1.2, and a growth rate is 50 ?m/h or more from an initial growth stage.
    Type: Application
    Filed: April 19, 2018
    Publication date: March 12, 2020
    Applicants: SHOWA DENKO K.K., Central Research Institute of Electric Power Industry, DENSO CORPORATION
    Inventors: Keisuke FUKADA, Naoto ISHIBASHI, Akira BANDO, Masahiko ITO, Isaho KAMATA, Hidekazu TSUCHIDA, Kazukuni HARA, Masami NAITO, Hideyuki UEHIGASHI, Hiroaki FUJIBAYASHI, Hirofumi AOKI, Toshikazu SUGIURA, Katsumi SUZUKI
  • Patent number: 10584417
    Abstract: A film forming apparatus according to an embodiment of the invention includes: a film forming chamber configured to form a film on a substrate; a susceptor configured to place the substrate thereon; a rotating part configured to rotate the susceptor; a heater configured to heat the substrate; and a gas supplier configured to supply process gases into the film forming chamber, wherein the susceptor includes: a ring-shaped outer circumferential susceptor supported by the rotating part; a holder provided at an inner circumferential portion of the outer circumferential susceptor, the holder configured to hold the substrate; a ring-shaped plate provided over the outer circumferential susceptor; and a cover member configured to cover a top surface and an outer circumferential surface of the plate and an outer circumferential surface of the outer circumferential susceptor.
    Type: Grant
    Filed: July 10, 2015
    Date of Patent: March 10, 2020
    Assignee: NuFlare Technology, Inc.
    Inventors: Hideki Ito, Hidekazu Tsuchida, Isaho Kamata, Masahiko Ito, Masami Naito, Hiroaki Fujibayashi, Katsumi Suzuki, Koichi Nishikawa
  • Publication number: 20190376206
    Abstract: This SiC epitaxial wafer includes: a SiC single crystal substrate of which a main surface has an off-angle of 0.4° to 5° with respect to (0001) plane; and an epitaxial layer provided on the SiC single crystal substrate, wherein the epitaxial layer has a basal plane dislocation density of 0.1 pieces/cm2 or less that is a density of basal plane dislocations extending from the SiC single crystal substrate to an outer surface and an intrinsic 3C triangular defect density of 0.1 pieces/cm2 or less.
    Type: Application
    Filed: December 25, 2017
    Publication date: December 12, 2019
    Applicants: SHOWA DENKO K.K, Central Research Institute of Electric Power Industry, DENSO CORPORATION
    Inventors: Keisuke FUKADA, Naoto ISHIBASHI, Akira BANDO, Masahiko ITO, Isaho KAMATA, Hidekazu TSUCHIDA, Kazukuni HARA, Masami NAITO, Hideyuki UEHIGASHI, Hiroaki FUJIBAYASHI, Hirofumi AOKI, Toshikazu SUGIURA, Katsumi SUZUKI
  • Patent number: 10262863
    Abstract: A method for manufacturing a SiC epitaxial wafer according to one aspect of the present invention includes separately introducing, into a reaction space for SiC epitaxial growth, a basic N-based gas composed of molecules containing an N atom within the molecular structure but having neither a double bond nor a triple bond between nitrogen atoms, and a Cl-based gas composed of molecules containing a Cl atom within the molecular structure, and mixing the N-based gas and the Cl-based gas at a temperature equal to or higher than the boiling point or sublimation temperature of a solid product generated by mixing the N-based gas and the Cl-based gas.
    Type: Grant
    Filed: December 8, 2015
    Date of Patent: April 16, 2019
    Assignees: SHOWA DENKO K.K., Central Research Institute Of Electric Power Industry
    Inventors: Keisuke Fukada, Masahiko Ito, Isaho Kamata, Hidekazu Tsuchida, Hideyuki Uehigashi, Hiroaki Fujibayashi, Masami Naito, Kazukuni Hara, Takahiro Kozawa, Hirofumi Aoki
  • Patent number: 10181517
    Abstract: A silicon carbide single crystal includes: threading dislocations each of which having a dislocation line extending through a C-plane, and a Burgers vector including at least a component in a C-axis direction. In addition, a density of the threading dislocations having angles, each of which is formed by an orientation of the Burgers vector and an orientation of the dislocation line, larger than 0° and within 40° is set to 300 dislocations/cm2 or less. Furthermore, a density of the threading dislocations having the angles larger than 40° is set to 30 dislocations/cm2 or less.
    Type: Grant
    Filed: August 25, 2016
    Date of Patent: January 15, 2019
    Assignee: DENSO CORPORATION
    Inventors: Takeshi Okamoto, Hiroyuki Kondo, Takashi Kanemura, Shinichiro Miyahara, Yasuhiro Ebihara, Shoichi Onda, Hidekazu Tsuchida, Isaho Kamata, Ryohei Tanuma
  • Publication number: 20180374721
    Abstract: A supply part includes a first partition, a second partition under the first partition, a third partition under the second partition, a first flow path between the first partition and the second partition allowing a first gas to be introduced therein, a second flow path between the second partition and the third partition allowing a second gas to be introduced therein, a first piping extending from the second partition to reach below the third partition and being communicated with the first flow path, a second piping extending from the third partition to reach below the third partition and being communicated with the second flow path, and a convex portion provided on an outer circumferential surface of the first piping or an inner circumferential surface of the second piping protruding from one of the outer circumferential surface and the inner circumferential surface toward the other one.
    Type: Application
    Filed: August 31, 2018
    Publication date: December 27, 2018
    Inventors: Kunihiko Suzuki, Naohisa Ikeya, Keisuke Fukada, Masahiko Ito, Isaho Kamata, Hidekazu Tsuchida, Hiroaki Fujibayashi, Hideyuki Uehigashi, Masami Naito, Kazukuni Hara, Hirofumi Aoki, Takahiro Kozawa
  • Publication number: 20180219069
    Abstract: A silicon carbide single crystal includes: threading dislocations each of which having a dislocation line extending through a C-plane, and a Burgers vector including at least a component in a C-axis direction. In addition, a density of the threading dislocations having angles, each of which is formed by an orientation of the Burgers vector and an orientation of the dislocation line, larger than 0° and within 40° is set to 300 dislocations/cm2 or less. Furthermore, a density of the threading dislocations having the angles larger than 40° is set to 30 dislocations/cm2 or less.
    Type: Application
    Filed: August 25, 2016
    Publication date: August 2, 2018
    Inventors: Takeshi OKAMOTO, Hiroyuki KONDO, Takashi KANEMURA, Shinichiro MIYAHARA, Yasuhiro EBIHARA, Shoichi ONDA, Hidekazu TSUCHIDA, Isaho KAMATA, Ryohei TANUMA
  • Patent number: 9879359
    Abstract: In a silicon carbide semiconductor film forming apparatus, first to third gasses are introduced into first to third separation chambers through first to third inlets, respectively. The first and second gasses are silicon raw material including gas and carbon raw material including gas, and the third gas does not include silicon and carbon. The first and second gasses are independently supplied to growth space through first and second supply paths extending from the first and second separation chambers, respectively. The third gas is introduced through a third supply path from the third separation chamber between the first and second gasses.
    Type: Grant
    Filed: June 19, 2014
    Date of Patent: January 30, 2018
    Assignees: DENSO CORPORATION, CENTRAL RESEARCH INSTITUTE OF ELECTRIC POWER INDUSTRY, NuFlare Technology, Inc., TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Hiroaki Fujibayashi, Masami Naito, Masahiko Ito, Isaho Kamata, Hidekazu Tsuchida, Hideki Ito, Ayumu Adachi, Koichi Nishikawa
  • Patent number: 9873941
    Abstract: It is an object of the present invention to provide a film-forming apparatus and a film-forming method that can prolong the lifetime of heaters used under high temperature conditions in an epitaxial growth technique. An inert gas discharge portion supplies an inert gas into the space containing the heater, gas is then discharged through the gas discharge portion without influence on the semiconductor substrate during film formation. It is therefore possible to prevent the reaction gas entering into the space containing the high-temperature heaters. This makes it possible to prevent a reaction between hydrogen gas contained in the reaction gas and SiC constituting the heaters. Therefore, it is possible to prevent carbon used as a base material of the heaters from being exposed due to the decomposition of SiC and then reacting with hydrogen gas. This makes it possible to prolong the lifetime of the heaters.
    Type: Grant
    Filed: July 29, 2015
    Date of Patent: January 23, 2018
    Assignees: NuFlare Technology, Inc., Toyota Jidosha Kabushiki Kaisha
    Inventors: Hideki Ito, Toshiro Tsumori, Kunihiko Suzuki, Hidekazu Tsuchida, Isaho Kamata, Masahiko Ito, Masami Naito, Hiroaki Fujibayashi, Ayumu Adachi, Koichi Nishikawa
  • Publication number: 20170345658
    Abstract: A method for manufacturing a SiC epitaxial wafer according to one aspect of the present invention includes separately introducing, into a reaction space for SiC epitaxial growth, a basic N-based gas composed of molecules containing an N atom within the molecular structure but having neither a double bond nor a triple bond between nitrogen atoms, and a Cl-based gas composed of molecules containing a Cl atom within the molecular structure, and mixing the N-based gas and the Cl-based gas at a temperature equal to or higher than the boiling point or sublimation temperature of a solid product generated by mixing the N-based gas and the Cl-based gas.
    Type: Application
    Filed: December 8, 2015
    Publication date: November 30, 2017
    Applicants: SHOWA DENKO K.K., Central Research Institute of Electric Power Industry
    Inventors: Keisuke FUKADA, Masahiko ITO, Isaho KAMATA, Hidekazu TSUCHIDA, Hideyuki UEHIGASHI, Hiroaki FUJIBAYASHI, Masami NAITO, Kazukuni HARA, Takahiro KOZAWA, Hirofumi AOKI
  • Patent number: 9598792
    Abstract: A film-forming apparatus and method comprising a film-forming chamber for supplying a reaction gas into, a cylindrical shaped liner provided between an inner wall of the film-forming chamber and a space for performing a film-forming process, a main-heater for heating a substrate placed inside the liner, from the bottom side, a sub-heater cluster provided between the liner and the inner wall, for heating the substrate from the top side, wherein the main-heater and the sub-heater cluster are resistive heaters, wherein the sub-heater cluster has a first sub-heater provided at the closest position to the substrate, and a second sub-heater provided above the first sub-heater, wherein the first sub-heater heats the substrate in combination with the main-heater, the second sub-heater heats the liner at a lower output than the first sub-heater, wherein each temperature of the main-heater, the first sub-heater, and the second sub-heater is individually controlled.
    Type: Grant
    Filed: June 19, 2012
    Date of Patent: March 21, 2017
    Assignees: NuFlare Technology, Inc., Central Research Institute of Electric Power Industry, Denso Corporation, Toyota Jidosha Kabushiki Kaisha
    Inventors: Kunihiko Suzuki, Hideki Ito, Naohisa Ikeya, Hidekazu Tsuchida, Isaho Kamata, Masahiko Ito, Masami Naito, Hiroaki Fujibayashi, Ayumu Adachi, Koichi Nishikawa
  • Patent number: 9570337
    Abstract: At the time of transporting a substrate into or from a space where a film formation process is performed, the space where the film formation process is performed, a space where a lower heater 16 is provided, and a space where an upper heater 19 is provided are made in an inert gas atmosphere.
    Type: Grant
    Filed: March 19, 2014
    Date of Patent: February 14, 2017
    Assignees: NuFlare Technology, Inc., Denso Corporation
    Inventors: Hideki Ito, Hidekazu Tsuchida, Isaho Kamata, Masahiko Ito, Masami Naito, Hiroaki Fujibayashi, Ayumu Adachi, Koichi Nishikawa
  • Patent number: 9518322
    Abstract: A film formation apparatus according to an embodiment includes: a film formation chamber performing film formation on a substrate; a cylindrical liner provided inside of a sidewall of the film formation chamber; a process-gas supply unit provided at a top of the film formation chamber and having a first gas ejection hole supplying a process gas to inside of the liner; a first heater provided outside the liner in the film formation chamber and heating the substrate from above; a second heater heating the substrate from below; and a shielding gas supply unit having a plurality of second gas ejection holes supplying a shielding gas to a position closer to a sidewall of the film formation chamber than a position of the first gas ejection hole.
    Type: Grant
    Filed: August 29, 2014
    Date of Patent: December 13, 2016
    Assignee: NuFlare Technology, Inc.
    Inventors: Hideki Ito, Kunihiko Suzuki, Hidekazu Tsuchida, Isaho Kamata, Masahiko Ito, Hiroaki Fujibayashi, Masami Naito, Ayumu Adachi, Koichi Nishikawa
  • Publication number: 20160138190
    Abstract: In a silicon carbide semiconductor film forming apparatus, first to third gasses are introduced into first to third separation chambers through first to third inlets, respectively. The first and second gasses are silicon raw material including gas and carbon raw material including gas, and the third gas does not include silicon and carbon. The first and second gasses are independently supplied to growth space through first and second supply paths extending from the first and second separation chambers, respectively. The third gas is introduced through a third supply path from the third separation chamber between the first and second gasses.
    Type: Application
    Filed: June 19, 2014
    Publication date: May 19, 2016
    Inventors: Hiroaki FUJIBAYASHI, Masami NAITO, Masahiko ITO, Isaho KAMATA, Hidekazu TSUCHIDA, Hideki ITO, Ayumu ADACHI, Koichi NISHIKAWA