Patents by Inventor Kota Umezawa

Kota Umezawa 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).

  • Patent number: 9966258
    Abstract: There is provided a method of growing a gallium nitride-based crystal, including: forming an interlayer including aluminum nitride or aluminum oxide on a silicon substrate at a film forming temperature of 350 to 700 degrees C.; heating the silicon substrate and the interlayer in an atmosphere containing ammonia or oxygen such that crystal nuclei of the aluminum nitride or the aluminum oxide included in the interlayer are distributed on the silicon substrate; and growing gallium nitride-based crystals on the silicon substrate from the crystal nuclei distributed on the silicon substrate.
    Type: Grant
    Filed: January 28, 2015
    Date of Patent: May 8, 2018
    Assignee: TOKYO ELECTRON LIMITED
    Inventors: Kota Umezawa, Yosuke Watanabe
  • Publication number: 20160265136
    Abstract: A film forming method for forming an aluminum nitride film on a substrate in which at least a surface portion is formed of a single crystal silicon through an epitaxial growth under a vacuum atmosphere, includes performing one or more times a cycle including a first process of supplying a raw material gas containing an aluminum compound to the substrate and a second process of supplying an ammonia gas to form a seed layer formed of an aluminum nitride by a reaction of the ammonia gas and the aluminum compound adsorbed onto the silicon substrate, and simultaneously supplying the raw material gas containing the aluminum compound and the ammonia gas to form an aluminum nitride film on the seed layer.
    Type: Application
    Filed: March 1, 2016
    Publication date: September 15, 2016
    Inventors: Kota UMEZAWA, Yosuke WATANABE
  • Publication number: 20150221512
    Abstract: There is provided a method of growing a gallium nitride-based crystal, including: forming an interlayer including aluminum nitride or aluminum oxide on a silicon substrate at a film forming temperature of 350 to 700 degrees C.; heating the silicon substrate and the interlayer in an atmosphere containing ammonia or oxygen such that crystal nuclei of the aluminum nitride or the aluminum oxide included in the interlayer are distributed on the silicon substrate; and growing gallium nitride-based crystals on the silicon substrate from the crystal nuclei distributed on the silicon substrate.
    Type: Application
    Filed: January 28, 2015
    Publication date: August 6, 2015
    Inventors: Kota UMEZAWA, Yosuke WATANABE
  • Publication number: 20140318457
    Abstract: A film forming apparatus includes: a processing chamber configured to accommodate a substrate to be processed, the processing chamber performing a film forming process forming a compound semiconductor film; a heating device configured to heat the substrate to be processed; an exhaust device configured to exhaust an interior of the processing chamber, and a process gas supply mechanism configured to supply a gas to the processing chamber. In addition, a method of cleaning the film forming apparatus includes: performing a process of cleaning the interior of the processing chamber and a member; performing a process of cleaning lower portions of the interior of the processing chamber and the member, respectively; and performing a process of cleaning a gas supply channel, wherein the processes are performed by controlling the pressure and temperature inside the processing chamber and supplying a cleaning gas from the gas supply channel.
    Type: Application
    Filed: April 25, 2014
    Publication date: October 30, 2014
    Applicant: TOKYO ELECTRON LIMITED
    Inventors: Kota UMEZAWA, Yosuke WATANABE
  • Publication number: 20140038394
    Abstract: A method for forming a compound semiconductor film on a substrate to be processed, which includes: mounting a plurality of substrates to be processed on a substrate mounting jig; loading the substrates to be processed into a processing chamber; and heating the substrates to be processed loaded into the processing chamber; supplying a gas containing one element that constitutes a compound semiconductor, and another gas containing another element that constitutes the compound semiconductor and being different from the one element, into the processing chamber in which the substrates to be processed are loaded; and forming the compound semiconductor film on each of the substrates to be processed.
    Type: Application
    Filed: August 2, 2013
    Publication date: February 6, 2014
    Applicant: TOKYO ELECTRON LIMITED
    Inventors: Yosuke WATANABE, Kota UMEZAWA
  • Publication number: 20120164848
    Abstract: A plasma-assisted ALD method using a vertical furnace and being performed by repeating a cycle until a desired film thickness is obtained is disclosed. The cycle comprises introducing a source gas containing a source to be nitrided, adsorbing, purging, introducing a nitriding gas and nitriding the source, and then, purging. A flow rate of a second carrier gas during introduction of the nitriding gas is reduced relative to that of a first carrier gas during introduction of the source gas. Particularly, a flow ratio of NH3 gas as the nitriding gas to N2 gas as the second carrier gas is 50:3 or less.
    Type: Application
    Filed: December 28, 2011
    Publication date: June 28, 2012
    Applicants: Tokyo Electron Limited, Elpida Memory, Inc.
    Inventors: Motoki FUJII, Masanobu MATSUNAGA, Kazuya YAMAMOTO, Kota UMEZAWA
  • Patent number: 8183158
    Abstract: A method for using a semiconductor processing apparatus includes supplying an oxidizing gas and a reducing gas into a process container of the processing apparatus accommodating no product target substrate therein; causing the oxidizing gas and the reducing gas to react with each other within a first atmosphere that activates the oxidizing gas and the reducing gas inside the process container, thereby generating radicals; and removing a contaminant from an inner surface of the process container by use of the radicals.
    Type: Grant
    Filed: October 17, 2007
    Date of Patent: May 22, 2012
    Assignee: Tokyo Electron Limited
    Inventors: Masahiko Tomita, Kota Umezawa, Ryou Son, Toshiharu Nishimura
  • Publication number: 20110281443
    Abstract: The film formation method includes transferring an object to be processed into a process chamber; controlling a temperature of the object to be processed to be equal to or lower than 350° C.; and supplying an aminosilane gas as a Si source gas and an oxidizing gas into the process chamber, wherein the oxidizing gas consists of a first oxidizing gas comprising at least one selected from the group consisting of an O2 gas and an O3 gas, and a second oxidizing gas comprising at least one selected from the group consisting of a H2O gas and a H2O2 gas, thereby forming a silicon oxide film on a surface of the object to be processed.
    Type: Application
    Filed: May 12, 2011
    Publication date: November 17, 2011
    Applicant: TOKYO ELECTRON LIMITED
    Inventors: Pao-Hwa CHOU, Kota UMEZAWA, Yosuke WATANABE, Masayuki HASEGAWA
  • Patent number: 7981809
    Abstract: A film formation method for a semiconductor process for forming a silicon oxynitride film on a target substrate within a reaction chamber includes a step of performing a pre-process on members inside the reaction chamber without the target substrate loaded therein, and a step of then forming a silicon oxynitride film on the target substrate within the reaction chamber. The pre-process is arranged to supply a pre-process gas containing a nitriding gas or oxynitriding gas into the reaction chamber, and setting an interior of the reaction chamber at a first temperature and a first pressure.
    Type: Grant
    Filed: December 12, 2005
    Date of Patent: July 19, 2011
    Assignee: Tokyo Electron Limited
    Inventors: Tetsuya Shibata, Yutaka Takahashi, Kota Umezawa, Masahiko Tomita
  • Patent number: 7964241
    Abstract: An insulating film is formed on a target substrate by CVD, in a process field to be selectively supplied with a first process gas containing a silane family gas, a second process gas containing a nitriding gas or oxynitriding gas, a third process gas containing a boron-containing gas, and a fourth process gas containing a carbon hydride gas. A first step performs supply of the first process gas and a preceding gas, which is one of the third and fourth process gases, while stopping supply of the second process gas and a succeeding gas, which is the other of the third and fourth process gases. A second step performs supply of the succeeding gas, while stopping supply of the second process gas and the preceding gas. A third step performs supply of the second process gas while stopping supply of the first process gas.
    Type: Grant
    Filed: August 28, 2007
    Date of Patent: June 21, 2011
    Assignee: Tokyo Electron Limited
    Inventors: Kazuhide Hasebe, Pao-Hwa Chou, Kota Umezawa, Kentaro Kadonaga, Hao-Hsiang Chang
  • Patent number: 7674724
    Abstract: An oxidizing method for an object to be processed according to the present invention includes: an arranging step of arranging a plurality of objects to be processed in a processing container whose inside can be vacuumed, the processing container having a predetermined length, a supplying unit of an oxidative gas being provided at one end of the processing container, a plurality of supplying units of a reducing gas being provided at a plurality of positions in a longitudinal direction of the processing container; an atmosphere forming step of supplying the oxidative gas and the reducing gas into the processing container in order to form an atmosphere having active oxygen species and active hydroxyl species in the processing container; and an oxidizing step of oxidizing surfaces of the plurality of objects to be processed in the atmosphere.
    Type: Grant
    Filed: June 24, 2008
    Date of Patent: March 9, 2010
    Assignee: Tokyo Electron Limited
    Inventors: Keisuke Suzuki, Toshiyuki Ikeuchi, Kota Umezawa
  • Patent number: 7605095
    Abstract: A heat processing method for a semiconductor process includes placing a plurality of target substrates stacked at intervals in a vertical direction within a process field of a process container. Each of the target substrates includes a process object layer on its surface. Then, the method includes supplying an oxidizing gas and a deoxidizing gas to the process field while heating the process field, thereby causing the oxidizing gas and the deoxidizing gas to react with each other to generate oxygen radicals and hydroxyl group radicals, and performing oxidation on the process object layer of the target substrates by use of the oxygen radicals and the hydroxyl group radicals. Then, the method includes heating the process object layer processed by the oxidation, within an atmosphere of an annealing gas containing ozone or oxidizing radicals, thereby performing annealing on the process object layer.
    Type: Grant
    Filed: February 6, 2008
    Date of Patent: October 20, 2009
    Assignee: Tokyo Electron Limited
    Inventors: Toshiyuki Ikeuchi, Kota Umezawa, Tetsuya Shibata
  • Publication number: 20080311760
    Abstract: A silicon nitride film is formed on a target substrate by performing a plurality of cycles in a process field configured to be selectively supplied with a first process gas containing a silane family gas and a second process gas containing a nitriding gas. Each of the cycles includes a first supply step of performing supply of the first process gas while maintaining a shut-off state of supply of the second process gas, and a second supply step of performing supply of the second process gas, while maintaining a shut-off state of supply of the first process gas. The method is arranged to repeat a first cycle set with the second supply step including an excitation period of exciting the second process gas and a second cycle set with the second supply step including no period of exciting the second process gas.
    Type: Application
    Filed: June 6, 2008
    Publication date: December 18, 2008
    Inventors: Nobutake Nodera, Masanobu Matsunaga, Kazuhide Hasebe, Kota Umezawa, Pao-Hwa Chou
  • Patent number: 7452826
    Abstract: An oxidation method is capable of forming oxide films in an improved interfilm thickness uniformity. The oxidation method includes the steps of supplying an oxidizing gas and a reducing gas into a processing vessel 22 capable of being evacuated and holding a plurality of workpieces W arranged at predetermined pitches, and creating a process atmosphere containing active oxygen species and active hydroxyl species in the processing vessel 22 through the interaction of the oxidizing gas-and the reducing gas. At least either of the oxidizing gas and the reducing gas is jetted into an upstream region S1, a middle region S2 and a downstream region S3, with respect to the flowing direction of the gas, of a processing space S containing the workpieces W.
    Type: Grant
    Filed: August 11, 2006
    Date of Patent: November 18, 2008
    Assignee: Tokyo Electron Limited
    Inventors: Kazuhide Hasebe, Kota Umezawa, Yutaka Takahashi
  • Publication number: 20080268654
    Abstract: An oxidizing method for an object to be processed according to the present invention includes: an arranging step of arranging a plurality of objects to be processed in a processing container whose inside can be vacuumed, the processing container having a predetermined length, a supplying unit of an oxidative gas being provided at one end of the processing container, a plurality of supplying units of a reducing gas being provided at a plurality of positions in a longitudinal direction of the processing container; an atmosphere forming step of supplying the oxidative gas and the reducing gas into the processing container in order to form an atmosphere having active oxygen species and active hydroxyl species in the processing container; and an oxidizing step of oxidizing surfaces of the plurality of objects to be processed in the atmosphere.
    Type: Application
    Filed: June 24, 2008
    Publication date: October 30, 2008
    Inventors: Keisuke Suzuki, Toshiyuki Ikouchi, Kota Umezawa
  • Patent number: 7419550
    Abstract: An oxidizing method for includes: an arranging step of arranging a plurality of objects to be processed in a processing container whose inside can be vacuumed, a supplying unit of an oxidative gas being provided at one end of the processing container, a plurality of supplying units of a reducing gas being provided at a plurality of positions in a longitudinal direction of the processing container; an atmosphere forming step of supplying the oxidative gas and the reducing gas into the processing container in order to form active oxygen species and active hydroxyl species; and an oxidizing step of oxidizing surfaces of the plurality of objects.
    Type: Grant
    Filed: February 17, 2005
    Date of Patent: September 2, 2008
    Assignee: Tokyo Electron Limited
    Inventors: Keisuke Suzuki, Toshiyuki Ikeuchi, Kota Umezawa
  • Publication number: 20080200038
    Abstract: A heat processing method for a semiconductor process includes placing a plurality of target substrates stacked at intervals in a vertical direction within a process field of a process container. Each of the target substrates includes a process object layer on its surface. Then, the method includes supplying an oxidizing gas and a deoxidizing gas to the process field while heating the process field, thereby causing the oxidizing gas and the deoxidizing gas to react with each other to generate oxygen radicals and hydroxyl group radicals, and performing oxidation on the process object layer of the target substrates by use of the oxygen radicals and the hydroxyl group radicals. Then, the method includes heating the process object layer processed by the oxidation, within an atmosphere of an annealing gas containing ozone or oxidizing radicals, thereby performing annealing on the process object layer.
    Type: Application
    Filed: February 6, 2008
    Publication date: August 21, 2008
    Inventors: Toshiyuki Ikeuchi, Kota Umezawa, Tetsuya Shibata
  • Publication number: 20080093023
    Abstract: A method for using a semiconductor processing apparatus includes supplying an oxidizing gas and a reducing gas into a process container of the processing apparatus accommodating no product target substrate therein; causing the oxidizing gas and the reducing gas to react with each other within a first atmosphere that activates the oxidizing gas and the reducing gas inside the process container, thereby generating radicals; and removing a contaminant from an inner surface of the process container by use of the radicals.
    Type: Application
    Filed: October 17, 2007
    Publication date: April 24, 2008
    Inventors: Masahiko Tomita, Kota Umezawa, Ryou Son, Toshiharu Nishimura
  • Publication number: 20080063791
    Abstract: An insulating film is formed on a target substrate by CVD, in a process field to be selectively supplied with a first process gas containing a silane family gas, a second process gas containing a nitriding gas or oxynitriding gas, a third process gas containing a boron-containing gas, and a fourth process gas containing a carbon hydride gas. A first step performs supply of the first process gas and a preceding gas, which is one of the third and fourth process gases, while stopping supply of the second process gas and a succeeding gas, which is the other of the third and fourth process gases. A second step performs supply of the succeeding gas, while stopping supply of the second process gas and the preceding gas. A third step performs supply of the second process gas while stopping supply of the first process gas.
    Type: Application
    Filed: August 28, 2007
    Publication date: March 13, 2008
    Inventors: Kazuhide Hasebe, Pao-Hwa Chou, Kota Umezawa, Kentaro Kadonaga, Hao-Hsiang Chang
  • Patent number: 7208428
    Abstract: A thermal treatment apparatus 1 includes a reaction tube 2 for containing wafers 10 contaminated with organic substances having a heater 12 capable of heating the reaction tube; a first gas supply pipe 13 for carrying oxygen gas into the reaction tube 2; and a second gas supply pipe 14 for carrying hydrogen gas into the reaction tube 2. Oxygen gas and hydrogen gas are supplied through the first gas supply pipe 13 and the second gas supply pipe 14, respectively, into the reaction tube 2, and the heater 12 heats the reaction tube 2 at a temperature capable of activating oxygen gas and hydrogen gas. A combustion reaction occurs in the reaction tube 2 and thereby the organic substances adhering to the wafers 10 are oxidized, decomposed and removed.
    Type: Grant
    Filed: December 4, 2001
    Date of Patent: April 24, 2007
    Assignee: Tokyo Electron Limited
    Inventors: Shingo Hishiya, Yoshikazu Furusawa, Teruyuki Hayashi, Misako Saito, Kota Umezawa, Syoichi Sato