Patents by Inventor Masanori Morishita

Masanori Morishita 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: 20110100292
    Abstract: A method for growing a GaN crystal includes a step of preparing a substrate (10) that includes a main surface (10m) and includes a Gax Aly In1-x-y N seed crystal (10a) including the main surface (10m) and a step of growing a GaN crystal (20) on the main surface (10m) at an atmosphere temperature of 800° C. or more and 1500° C. or less and at an atmosphere pressure of 500 atmospheres or more and less than 2000 atmospheres by bringing a solution (7) provided by dissolving (5) nitrogen in a Ga melt (3) into contact with the main surface (10m) of the substrate (10). The method further includes, after the step of preparing the substrate (10) and before the step of growing the GaN crystal (20), a step of etching the main surface (10m) of the substrate (10). Thus, a method for growing a GaN crystal having a low dislocation density and high crystallinity is provided without adding impurities other than raw materials to the melt and without increasing the size of a crystal growth apparatus.
    Type: Application
    Filed: July 14, 2009
    Publication date: May 5, 2011
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Koji Uematsu, Hiroaki Yoshida, Masanori Morishita, Shinsuke Fujiwara
  • Publication number: 20100139553
    Abstract: Affords a method of growing, across the entirety of a major surface of a first III-nitride crystal, a second III-nitride crystal by HVPE, in an ambient temperature higher than 1100° C. The present III-nitride crystal growth method comprises: a step of preparing a first III-nitride crystal (10) having an alkali-metal atom concentration of less than 1.0×1018 cm?3; and a step of growing a second III-nitride crystal (20) onto a major surface (10m) of the first III-nitride crystal (10) by HVPE, in an ambient temperature higher than 1100° C.
    Type: Application
    Filed: December 3, 2009
    Publication date: June 10, 2010
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Hiroaki Yoshida, Shinsuke Fujiwara, Koji Uematsu, Masanori Morishita
  • Publication number: 20100059717
    Abstract: A method for producing a GaN crystal capable of achieving at least one of the prevention of nucleation and the growth of a high-quality non-polar surface is provided. The production method of the present invention is a method for producing a GaN crystal in a melt containing at least an alkali metal and gallium, including an adjustment step of adjusting the carbon content of the melt, and a reaction step of causing the gallium and nitrogen to react with each other. According to the production method of the present invention, nucleation can be prevented, and as shown in FIG. 4, a non-polar surface can be grown.
    Type: Application
    Filed: November 14, 2007
    Publication date: March 11, 2010
    Applicants: OSAKA UNIVERSITY, OSAKA INDUSTRIAL PROMOTION ORGANIZATION
    Inventors: Yusuke Mori, Takatomo Sasaki, Fumio Kawamura, Masashi Yoshimura, Minoru Kawahara, Yasuo Kitaoka, Masanori Morishita
  • Patent number: 7507292
    Abstract: A method for producing a Group III element nitride single crystal, which comprises reacting at least one Group III element selected from the group consisting of gallium(Ga), aluminum(Al) and indium(In) with nitrogen(N) in a mixed flux of sodium(Na) and at least one of an alkali metal (except Na) and an alkaline earth metal. The method allows the production, with a good yield, of the single crystal of a group III element nitride which is transparent, is reduced in the density of dislocation, has a bulk form, and is large. In particular, a gallium nitride single crystal produced by the method has high quality and takes a large and transparent bulk form, and thus has a high practical value.
    Type: Grant
    Filed: June 30, 2003
    Date of Patent: March 24, 2009
    Assignee: Osaka Industrial Promotion Organization
    Inventors: Takatomo Sasaki, Yusuke Mori, Masashi Yoshimura, Fumio Kawamura, Kunimichi Omae, Tomoya Iwahashi, Masanori Morishita
  • Patent number: 7309534
    Abstract: The present invention provides a method of manufacturing Group III nitride crystals that are of high quality, are manufactured highly efficiently, and are useful and usable as a substrate that is used in semiconductor manufacturing processes.
    Type: Grant
    Filed: May 27, 2004
    Date of Patent: December 18, 2007
    Assignees: Matsushita Electric INdustrial Co., Ltd.
    Inventors: Yasuo Kitaoka, Hisashi Minemoto, Isao Kidoguchi, Takatomo Sasaki, Yusuke Mori, Fumio Kawamura, Masanori Morishita
  • Patent number: 7288152
    Abstract: The present invention provides a manufacturing method in which high quality GaN crystals and GaN crystal substrates can be manufactured under mild conditions of low pressure and low temperature. In a method of manufacturing GaN crystals in which in a gas atmosphere containing nitrogen, gallium and the nitrogen are allowed to react with each other to generate GaN crystals in a mixed melt of the gallium and sodium, the gallium and the nitrogen are allowed to react with each other under a pressurizing condition that exceeds atmospheric pressure, and pressure P1 (atm(×1.013×105 Pa)) of the pressurizing condition is set so as to satisfy the condition that is expressed by the following conditional expression (I): P?P1<(P+45),??(I) where in the expression (I), P (atm(×1.013×105 Pa)) denotes the minimum pressure that is required for generating GaN crystals at a temperature T° C. of the mixed melt.
    Type: Grant
    Filed: July 2, 2004
    Date of Patent: October 30, 2007
    Assignees: Matsushita Electric Industrial Co., Ltd., Yusuke MORI
    Inventors: Yasuo Kitaoka, Hisashi Minemoto, Isao Kidoguchi, Takatomo Sasaki, Yusuke Mori, Fumio Kawamura, Masanori Morishita
  • Publication number: 20060051942
    Abstract: A method for producing a Group III element nitride single crystal, which comprises reacting at least one Group III element selected from the group consisting of gallium(Ga), aluminum(Al) and indium(In) with nitrogen(N) in a mixed flux of sodium(Na) and at least one of an alkali metal (except Na) and an alkaline earth metal. The method allows the production, with a good yield, of the single crystal of a group III element nitride which is transparent, is reduced in the density of dislocation, has a bulk form, and is large. In particular, a gallium nitride single crystal produced by the method has high quality and takes a large and transparent bulk form, and thus has a high practical value.
    Type: Application
    Filed: June 30, 2003
    Publication date: March 9, 2006
    Applicant: Osaka Industrial Promotion Organization
    Inventors: Takatomo Sasaki, Yusuke Mori, Masashi Yoshimura, Fumio Kawamura, Kunimichi Omae, Tomoya Iwahashi, Masanori Morishita
  • Publication number: 20050048686
    Abstract: The present invention provides a manufacturing method in which high quality GaN crystals and GaN crystal substrates can be manufactured under mild conditions of low pressure and low temperature. In a method of manufacturing GaN crystals in which in a gas atmosphere containing nitrogen, gallium and the nitrogen are allowed to react with each other to generate GaN crystals in a mixed melt of the gallium and sodium, the gallium and the nitrogen are allowed to react with each other under a pressurizing condition that exceeds atmospheric pressure, and pressure P1 (atm (×1.013×105 Pa)) of the pressurizing condition is set so as to satisfy the condition that is expressed by the following conditional expression (I): P?P1<(P+45)??(I), where in the expression (I), P(atm (×1.013×105 Pa)) denotes the minimum pressure that is required for generating GaN crystals at a temperature T°C. of the mixed melt.
    Type: Application
    Filed: July 2, 2004
    Publication date: March 3, 2005
    Applicants: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Yasuo Kitaoka, Hisashi Minemoto, Isao Kidoguchi, Takatomo Sasaki, Yusuke Mori, Fumio Kawamura, Masanori Morishita
  • Publication number: 20040262630
    Abstract: The present invention provides a method of manufacturing Group III nitride crystals that are of high quality, are manufactured highly efficiently, and are useful and usable as a substrate that is used in semiconductor manufacturing processes.
    Type: Application
    Filed: May 27, 2004
    Publication date: December 30, 2004
    Applicants: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD., Yusuke MORI
    Inventors: Yasuo Kitaoka, Hisashi Minemoto, Isao Kidoguchi, Takatomo Sasaki, Yusuke Mori, Fumio Kawamura, Masanori Morishita