Patents by Inventor Takuya Kazama

Takuya Kazama 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: 20230357011
    Abstract: A method for manufacturing Group-III nitride semiconductor nanoparticles includes synthesizing Group-III nitride semiconductor nanoparticles having a particle size of 16 nm or less by reacting materials containing one or more Group-III elements M in a liquid phase, wherein a coordination solvent is used, and trimethyl M is used as at least one Group-III element material among the materials containing one or more Group-III elements M.
    Type: Application
    Filed: September 13, 2021
    Publication date: November 9, 2023
    Applicant: STANLEY ELECTRIC CO., LTD.
    Inventors: Takuya KAZAMA, Wataru TAMURA, Yasuyuki MIYAKE, Kenji MORIYAMA, Atsushi MURAMATSU, Kiyoshi KANIE
  • Patent number: 11788004
    Abstract: A quantum dot includes a nano-seed particle having a particular crystal plane exposed, and a first epitaxial layer formed on the particular crystal plane of the nano-seed particle.
    Type: Grant
    Filed: March 24, 2021
    Date of Patent: October 17, 2023
    Assignee: STANLEY ELECTRIC CO., LTD.
    Inventors: Takuya Kazama, Wataru Tamura, Yasuyuki Miyake
  • Patent number: 11767469
    Abstract: Provided are group-III nitride nanoparticles that prevent the piezoelectric field caused by strains on the nanoparticles, achieving good luminous efficiency. The group-III nitride nanoparticle represented by AlxGayInzN (0?x, y, z?1) incorporating two crystal structures; a wurtzite structure and a zincblende structure, in a single particle. As another example, the group-III nitride nanoparticle has a core-shell structure with a core and a shell, in which the particle constituting the core contains two crystal structures; the wurtzite structure and the zincblende structure, in the particle. Nanoparticles containing the two crystal structures can be produced by using a phosphorus-containing solvent as a reaction solvent, and the mixture ratio of the two crystal structures, (wurtzite structure)/(zincblende structure), is 20/80 or higher.
    Type: Grant
    Filed: September 29, 2021
    Date of Patent: September 26, 2023
    Assignee: STANLEY ELECTRIC CO., LTD.
    Inventors: Takuya Kazama, Wataru Tamura, Yasuyuki Miyake, Takayuki Omori, Atsushi Muramatsu, Kiyoshi Kanie
  • Publication number: 20230257281
    Abstract: A LiMnO2 production method includes generating cubic crystal LiMnO2 nanoparticles by adding an organic solvent, manganese oxide nanoparticles, and lithium amide in a reaction vessel and heating in an inert atmosphere. and a washing and recovering the generated particles. Wurtzite type MnO nanoparticles are preferably used as the manganese oxide. As a result, LiMnO2 nanoparticles that have a substantially similar particle size to wurtzite type MnO nanoparticles can be obtained from an Mn raw material. Nanoparticles having a hollow structure can be obtained by controlling the reaction temperature.
    Type: Application
    Filed: August 3, 2021
    Publication date: August 17, 2023
    Applicants: STANLEY ELECTRIC CO., LTD., TOHOKU UNIVERSITY
    Inventors: Masafumi NAKAYA, Takuya KAZAMA, Wataru TAMURA, Yasuyuki MIYAKE, Atsushi MURAMATSU, Kiyoshi KANIE
  • Publication number: 20220388862
    Abstract: Single-phase manganese oxide particles having a wurtzite crystal structure. The particles can be obtained by thermally decomposing a compound containing manganese. In this procedure, a reducing agent consisting of at least one of a polyol-based material and an ethylene glycol stearate-based material is added as an additive to the reaction system. It is heated at a first temperature (200° C. or lower) under a reduced pressure atmosphere, then the temperature is raised, and the product is heated at a temperature higher than the first temperature under an inert gas atmosphere.
    Type: Application
    Filed: November 9, 2020
    Publication date: December 8, 2022
    Applicant: STANLEY ELECTRIC CO., LTD.
    Inventors: Takuya KAZAMA, Wataru TAMURA, Yasuyuki MIYAKE, Kenji MORIYAMA, Atsushi MURAMATSU, Kiyoshi KANIE
  • Publication number: 20220098480
    Abstract: Provided are group-III nitride nanoparticles that prevent the piezoelectric field caused by strains on the nanoparticles, achieving good luminous efficiency. The group-III nitride nanoparticle represented by AlxGayInzN (0?x, y, z?1) incorporating two crystal structures; a wurtzite structure and a zincblende structure, in a single particle. As another example, the group-III nitride nanoparticle has a core-shell structure with a core and a shell, in which the particle constituting the core contains two crystal structures; the wurtzite structure and the zincblende structure, in the particle. Nanoparticles containing the two crystal structures can be produced by using a phosphorus-containing solvent as a reaction solvent, and the mixture ratio of the two crystal structures, (wurtzite structure)/(zincblende structure), is 20/80 or higher.
    Type: Application
    Filed: September 29, 2021
    Publication date: March 31, 2022
    Applicant: STANLEY ELECTRIC CO., LTD.
    Inventors: Takuya KAZAMA, Wataru TAMURA, Yasuyuki MIYAKE, Takayuki OMORI, Atsushi MURAMATSU, Kiyoshi KANIE
  • Publication number: 20210207025
    Abstract: A quantum dot includes a nano-seed particle having a particular crystal plane exposed, and a first epitaxial layer formed on the particular crystal plane of the nano-seed particle.
    Type: Application
    Filed: March 24, 2021
    Publication date: July 8, 2021
    Applicant: STANLEY ELECTRIC CO., LTD.
    Inventors: Takuya KAZAMA, Wataru TAMURA, Yasuyuki MIYAKE
  • Patent number: 10988688
    Abstract: A quantum dot manufacturing method comprises (a) dispersing, in a solvent, nano-seed particles whose crystal planes are exposed, and (b) growing semiconductor layers on the exposed crystal planes of the nano-seed particles in the solvent.
    Type: Grant
    Filed: August 1, 2017
    Date of Patent: April 27, 2021
    Assignee: STANLEY ELECTRIC CO., LTD.
    Inventors: Takuya Kazama, Wataru Tamura, Yasuyuki Miyake
  • Patent number: 10032955
    Abstract: A quantum dot having core-shell structure, including a core formed of ZnOzS1-z of wurtzite crystal structure of hexagonal crystal system; a first shell covering the core, and formed of AlxGayIn1-x-yN of wurtzite crystal structure of hexagonal crystal system; and a second shell covering the first shell, and formed of ZnOvS1-v of wurtzite crystal structure of hexagonal crystal system. At least one of v, x, y, and z is not zero and is not one; differences between the lattice constants along a-axis of the core, the first shell and the second shell are not greater than 1%; and the core, the first shell and the second shell form band offset structure of type II.
    Type: Grant
    Filed: September 7, 2017
    Date of Patent: July 24, 2018
    Assignee: STANLEY ELECTRIC CO., LTD.
    Inventors: Takuya Kazama, Wataru Tamura, Yasuyuki Miyake
  • Publication number: 20180026166
    Abstract: A manufacturing method of a quantum dot ensemble including quantum dots each having a composition represented by a formula AxB1-xCyD1-y (0?x?1, 0?y?1, A and B are elements selected from Zn and Mg, and C and D are elements selected from the group consisting of O, S, Se, and Te). The quantum dots forming the ensemble in a mixed manner, including (a) step of preparing a plurality of quantum dots each having a composition represented by a formula AxB1-xCyD1-y (0?x?1, 0?y?1, A and B are elements selected from the group consisting of Zn and Mg, and C and D are elements selected from the group consisting of O, S, Se, and Te); and (b) step of uniformizing band gap energy of the plurality of quantum dots by optically etching the plurality of quantum dots which are prepared in the step (a). In the step (a), target values of x and y in the formula AxB1-xCyD1-y are set in such a manner that band gap energy of AxB1-xCyD1-y attains an approximately minimal value.
    Type: Application
    Filed: September 18, 2017
    Publication date: January 25, 2018
    Applicant: STANLEY ELECTRIC CO., LTD.
    Inventors: Takuya KAZAMA, Yasuyuki MIYAKE, Wataru TAMURA
  • Publication number: 20170373223
    Abstract: A quantum dot having core-shell structure, including a core formed of ZnOzS1-z of wurtzite crystal structure of hexagonal crystal system; a first shell covering the core, and formed of AlxGayIn1-x-yN of wurtzite crystal structure of hexagonal crystal system; and a second shell covering the first shell, and formed of ZnOvS1-v of wurtzite crystal structure of hexagonal crystal system. At least one of v, x, y, and z is not zero and is not one; differences between the lattice constants along a-axis of the core, the first shell and the second shell are not greater than 1%; and the core, the first shell and the second shell form band offset structure of type II.
    Type: Application
    Filed: September 7, 2017
    Publication date: December 28, 2017
    Applicant: STANLEY ELECTRIC CO., LTD.
    Inventors: Takuya KAZAMA, Wataru TAMURA, Yasuyuki MIYAKE
  • Publication number: 20170355903
    Abstract: A quantum dot manufacturing method comprises (a) dispersing, in a solvent, nano-seed particles whose crystal planes are exposed, and (b) growing semiconductor layers on the exposed crystal planes of the nano-seed particles in the solvent.
    Type: Application
    Filed: August 1, 2017
    Publication date: December 14, 2017
    Applicant: STANLEY ELECTRIC CO., LTD.
    Inventors: Takuya KAZAMA, Wataru TAMURA, Yasuyuki MIYAKE
  • Patent number: 9773942
    Abstract: A quantum dot having core-shell structure includes a core formed of ZnOzS1-z, and at least one shell covering the core, and formed of AlxGayIn1-x-yN, wherein at least one of x, y, and z is not zero and is not one.
    Type: Grant
    Filed: January 19, 2016
    Date of Patent: September 26, 2017
    Assignee: STANLEY ELECTRIC CO., LTD.
    Inventors: Takuya Kazama, Wataru Tamura, Yasuyuki Miyake
  • Patent number: 9634200
    Abstract: A semiconductor light emitting device comprises a supporting substrate that has light reflecting characteristics; a wavelength conversion layer that is disposed on the supporting substrate, and contains semiconductor nanoparticles developing a quantum size effect; an optical semiconductor laminate that is disposed on the wavelength conversion layer and has light emitting characteristics; and a photonic crystal layer that is disposed on the optical semiconductor laminate, and that has first portions having a first refractive index and second portions having a second refractive index different from the first refractive index, the first portions and the second portions being arranged in a two-dimensional cyclic pattern.
    Type: Grant
    Filed: January 7, 2016
    Date of Patent: April 25, 2017
    Assignee: STANLEY ELECTRIC CO., LTD.
    Inventors: Takuya Kazama, Wataru Tamura, Yasuyuki Miyake
  • Publication number: 20160225958
    Abstract: A plurality of quantum dots are prepared. The plurality of prepared quantum dots are optically etched, and thus, have a uniformized band gap energy.
    Type: Application
    Filed: January 25, 2016
    Publication date: August 4, 2016
    Applicant: STANLEY ELECTRIC CO., LTD.
    Inventors: Takuya KAZAMA, Wataru TAMURA, Yasuyuki MIYAKE
  • Publication number: 20160211422
    Abstract: A semiconductor light emitting device comprises a supporting substrate that has light reflecting characteristics; a wavelength conversion layer that is disposed on the supporting substrate, and contains semiconductor nanoparticles developing a quantum size effect; an optical semiconductor laminate that is disposed on the wavelength conversion layer and has light emitting characteristics; and a photonic crystal layer that is disposed on the optical semiconductor laminate, and that has first portions having a first refractive index and second portions having a second refractive index different from the first refractive index, the first portions and the second portions being arranged in a two-dimensional cyclic pattern.
    Type: Application
    Filed: January 7, 2016
    Publication date: July 21, 2016
    Applicant: STANLEY ELECTRIC CO., LTD.
    Inventors: Takuya KAZAMA, Wataru TAMURA, Yasuyuki MIYAKE
  • Publication number: 20160211409
    Abstract: A quantum dot having core-shell structure includes a core formed of ZnOzS1-z, and at least one shell covering the core, and formed of AlxGayIn1-x-yN, wherein at least one of x, y, and z is not zero and is not one.
    Type: Application
    Filed: January 19, 2016
    Publication date: July 21, 2016
    Applicant: STANLEY ELECTRIC CO., LTD.
    Inventors: Takuya KAZAMA, Wataru TAMURA, Yasuyuki MIYAKE
  • Patent number: 9136435
    Abstract: A semiconductor light-emitting element includes a support substrate, a semiconductor film including a light-emitting layer provided on the support substrate, a surface electrode provided on a light-extraction-surface-side surface of the semiconductor film, and a light-reflecting layer provided between the support substrate and the semiconductor film, forming a light-reflecting surface. The surface electrode includes a first electrode piece and a second electrode piece. The light-reflecting layer includes a reflection electrode including a third electrode piece and a fourth electrode piece. The first electrode piece and the third electrode piece are arranged so as to not overlap when projected onto a projection surface parallel to a principal surface of the semiconductor film, and the shortest distance between the first electrode piece and the fourth electrode piece, is greater than the shortest distance between the first electrode piece and the third electrode piece.
    Type: Grant
    Filed: April 17, 2014
    Date of Patent: September 15, 2015
    Assignee: STANLEY ELECTRIC CO., LTD.
    Inventor: Takuya Kazama
  • Patent number: 9112113
    Abstract: A manufacturing method of a semiconductor element which can improve productivity and reliability, comprises a step of forming a device structure layer including a semiconductor layer on a first substrate; a step of forming a first metal layer on the device structure layer; a step of forming a second metal layer made of the same material as the first metal layer on a second substrate; a first treatment step of heating and compressing together the first metal layer and the second metal layer placed opposite to each other, thereby bonding them with maintaining a junction interface between the first and second metal layers; and a second treatment step of heating the first and second metal layers to make the junction interface disappear. Either one of the first and second metal layers has a coarse surface having multiple pyramid-shaped protrusions formed at its surface.
    Type: Grant
    Filed: February 20, 2013
    Date of Patent: August 18, 2015
    Assignee: STANLEY ELECTRIC CO., LTD.
    Inventor: Takuya Kazama
  • Patent number: 8981409
    Abstract: A semiconductor light emitting device comprises a first groove extending to a first semiconductor layer from a second semiconductor layer side through the second semiconductor layer and a light emitting layer; a first ohmic electrode formed in contact with the first semiconductor layer in the first groove; an insulating layer covering a surface of the second semiconductor layer and at least the surface of part of the light emitting layer exposed in the first groove; a metal layer covering the surface of the insulating layer and connected to the first ohmic electrode; a second groove extending from a first semiconductor layer side through the first semiconductor layer and the light emitting layer to the second semiconductor layer; a second ohmic electrode formed in contact with the second semiconductor layer in the second groove; and a support body bonded to the metal layer via a junction layer.
    Type: Grant
    Filed: July 30, 2013
    Date of Patent: March 17, 2015
    Assignee: Stanley Electric Co., Ltd.
    Inventor: Takuya Kazama