Patents by Inventor Takao Fujimori

Takao Fujimori 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: 20230253526
    Abstract: A semiconductor light-emitting element includes a substrate having a first surface, a plurality of protrusions disposed, with spacing opened between one another, on the first surface, a buffer layer disposed to cover the plurality of protrusions and the first surface positioned between the plurality of protrusions, a dimension of the buffer layer in a first direction orthogonal to the first surface being smaller than a dimension in the first direction of each of the plurality of protrusions, an n-type semiconductor layer that is disposed on the buffer layer and is doped with an n-type impurity, an active layer disposed on the n-type semiconductor layer, and a p-type semiconductor layer that is disposed on the active layer and is doped with a p-type impurity.
    Type: Application
    Filed: January 26, 2023
    Publication date: August 10, 2023
    Inventors: Ryosuke Ishimaru, Kazuaki Tsutsumi, Takao Fujimori
  • Patent number: 10529903
    Abstract: A light emitting device includes a light emitting layer, a substrate that is transparent to an emission wavelength of the light emitting layer and positioned to receive an emission wavelength from the light emitting layer, a convex pattern including a collection of a plurality of convex portions discretely arranged on a front surface of the substrate with a first pitch, an n type nitride semiconductor layer located on the front surface of the substrate to cover the convex pattern and a p type nitride semiconductor layer located on the light emitting layer. The light emitting layer is located on the n type semiconductor layer. Each of the convex portions includes a sub convex pattern comprising a plurality of fine convex portions discretely formed at the top of the convex portion with a second pitch smaller than the first pitch, and a base supporting the sub convex pattern.
    Type: Grant
    Filed: November 29, 2017
    Date of Patent: January 7, 2020
    Assignee: ROHM CO., LTD.
    Inventors: Nobuaki Matsui, Hirotaka Obuchi, Yasuo Nakanishi, Kazuaki Tsutsumi, Takao Fujimori
  • Patent number: 10497831
    Abstract: A semiconductor light emitting element is disclosed. The element includes a substrate including a first surface, a second surface opposite to the first surface, and a side surface that connects the first surface and the second surface; a semiconductor layer formed on the first surface of the substrate and configured to generate light; and a light reflective layer formed on the second surface of the substrate to cover an entire region of the second surface of the substrate and configured to reflect the light generated by the semiconductor layer toward the semiconductor layer. A modified layer, which has a physical property different from that of the other portion of the substrate, is formed on the side surface of the substrate to be spaced apart from the first surface toward the second surface by altering a material forming the substrate.
    Type: Grant
    Filed: June 1, 2017
    Date of Patent: December 3, 2019
    Assignee: ROHM CO., LTD.
    Inventors: Hirotaka Obuchi, Kazuaki Tsutsumi, Hideaki Anzai, Takao Fujimori
  • Patent number: 10263150
    Abstract: A semiconductor light emitting device includes a substrate having a first major surface and a second major surface, a semiconductor layer that includes a first semiconductor layer of a first conductive type formed on the first major surface of the substrate, a light emitting layer formed on the first semiconductor layer and a second semiconductor layer of a second conductive type formed on the light emitting layer, and a mesa structure formed in the semiconductor layer by selectively notching the first semiconductor layer, the light emitting layer and the second semiconductor layer so as to expose the first semiconductor layer, and a ratio of a luminescent area of the light emitting Layer with respect to an area of the first major surface of the substrate being set to equal to or smaller than 0.25.
    Type: Grant
    Filed: May 4, 2017
    Date of Patent: April 16, 2019
    Assignee: ROHM CO., LTD.
    Inventors: Takao Fujimori, Kazuaki Tsutsumi, Hirotaka Obuchi
  • Publication number: 20180351031
    Abstract: A light-emitting element, a light-emitting element unit and a light-emitting element package are provided, which are each reduced in reflection loss and intra-film light absorption by suppressing multiple light reflection in a transparent electrode layer and hence have higher luminance. The light-emitting element 1 includes a substrate 2, an n-type nitride semiconductor layer 3, a light-emitting layer 4, a p-type nitride semiconductor layer 5, a transparent electrode layer 6 and a reflective electrode layer 7, and the transparent electrode layer 6 has a thickness T satisfying the following expression (1): 3 ? ? 4 ? n + 0.30 × ( ? 4 ? n ) ? T ? 3 ? ? 4 ? n + 0.45 × ( ? 4 ? n ) ( 1 ) wherein ? is the light-emitting wavelength of the light-emitting element 4, and n is the refractive index of the transparent electrode layer 6.
    Type: Application
    Filed: August 9, 2018
    Publication date: December 6, 2018
    Applicant: ROHM CO., LTD.
    Inventors: Takao FUJIMORI, Yasuo NAKANISHI
  • Patent number: 10074767
    Abstract: A light-emitting element, a light-emitting element unit and a light-emitting element package are provided, which are each reduced in reflection loss and intra-film light absorption by suppressing multiple light reflection in a transparent electrode layer and hence have higher luminance. The light-emitting element 1 includes a substrate 2, an n-type nitride semiconductor layer 3, a light-emitting layer 4, a p-type nitride semiconductor layer 5, a transparent electrode layer 6 and a reflective electrode layer 7, and the transparent electrode layer 6 has a thickness T satisfying the following expression (1): 3 ? ? 4 ? n + 0.30 × ( ? 4 ? n ) ? T ? 3 ? ? 4 ? n + 0.45 × ( ? 4 ? n ) ( 1 ) wherein ? is the light-emitting wavelength of the light-emitting element 4, and n is the refractive index of the transparent electrode layer 6.
    Type: Grant
    Filed: July 31, 2017
    Date of Patent: September 11, 2018
    Assignee: ROHM CO., LTD.
    Inventors: Takao Fujimori, Yasuo Nakanishi
  • Patent number: 9997682
    Abstract: A light emitting element unit according to the present invention includes a semiconductor light emitting element that has a surface, a back surface, and a side surface, where the surface or the back surface is a light extracting surface from which light generated inside is emitted, a submount which has a bottom wall and a side wall, has a recess portion defined by the bottom wall and the side wall, and supports the semiconductor light emitting element by the bottom wall in a position in which the light extracting surface is directed upward at the recess portion, and has an inclined surface on the side wall, inclined at a predetermined angle with respect to the bottom wall so as to face the side surface of the semiconductor light emitting element, and a light reflecting film formed on the inclined surface of the submount.
    Type: Grant
    Filed: June 4, 2015
    Date of Patent: June 12, 2018
    Assignee: ROHM CO., LTD.
    Inventors: Takao Fujimori, Yasuo Nakanishi, Nobuaki Matsui, Hirotaka Obuchi
  • Patent number: 9991430
    Abstract: A light emitting device includes a light emitting layer, a substrate that is transparent to an emission wavelength of the light emitting layer and positioned to receive an emission wavelength from the light emitting layer, a convex pattern including a collection of a plurality of convex portions discretely arranged on a front surface of the substrate with a first pitch, an n type nitride semiconductor layer located on the front surface of the substrate to cover the convex pattern and a p type nitride semiconductor layer located on the light emitting layer. The light emitting layer is located on the n type semiconductor layer. Each of the convex portions includes a sub convex pattern comprising a plurality of fine convex portions discretely formed at the top of the convex portion with a second pitch smaller than the first pitch, and a base supporting the sub convex pattern.
    Type: Grant
    Filed: February 25, 2016
    Date of Patent: June 5, 2018
    Assignee: ROHM CO., LTD.
    Inventors: Nobuaki Matsui, Hirotaka Obuchi, Yasuo Nakanishi, Kazuaki Tsutsumi, Takao Fujimori
  • Publication number: 20180108809
    Abstract: The light emitting device includes a substrate, and an n-type conductive type semiconductor layer, a light emitting layer and a p-type conductive type semiconductor layer laminated in series on a surface of the substrate. The light emitting layer, the p-type conductive type semiconductor layer, and a portion of the n-type conductive type semiconductor layer excluding the vicinity of the peripheral portion compose a semiconductor laminate structure portion. A p-side transparent electrode layer is formed on a surface of the p-type conductive type semiconductor layer. The p-side transparent electrode covers a substantially whole area of a predetermined current injection region on a surface of the p-type conductive type semiconductor layer. A p-side electrode is formed on a surface of the p-side transparent electrode layer.
    Type: Application
    Filed: December 6, 2017
    Publication date: April 19, 2018
    Applicant: ROHM CO., LTD.
    Inventors: Takao FUJIMORI, Tomohito KAWASE, Yasuo NAKANISHI
  • Publication number: 20180083172
    Abstract: A light emitting device includes a light emitting layer, a substrate that is transparent to an emission wavelength of the light emitting layer and positioned to receive an emission wavelength from the light emitting layer, a convex pattern including a collection of a plurality of convex portions discretely arranged on a front surface of the substrate with a first pitch, an n type nitride semiconductor layer located on the front surface of the substrate to cover the convex pattern and a p type nitride semiconductor layer located on the light emitting layer. The light emitting layer is located on the n type semiconductor layer. Each of the convex portions includes a sub convex pattern comprising a plurality of fine convex portions discretely formed at the top of the convex portion with a second pitch smaller than the first pitch, and a base supporting the sub convex pattern.
    Type: Application
    Filed: November 29, 2017
    Publication date: March 22, 2018
    Applicant: ROHM CO., LTD.
    Inventors: Nobuaki MATSUI, Hirotaka OBUCHI, Yasuo NAKANISHI, Kazuaki TSUTSUMI, Takao FUJIMORI
  • Patent number: 9871166
    Abstract: The light emitting device 1 includes a substrate 2, and an n-type conductive type semiconductor layer 3, a light emitting layer 4 and a p-type conductive type semiconductor layer 5 laminated in series on a surface 2A of the substrate 2. The light emitting layer 4, the p-type conductive type semiconductor layer 5, and a portion of the n-type conductive type semiconductor layer 3 excluding the vicinity of the peripheral portion compose a semiconductor laminate structure portion 6. A p-side transparent electrode layer 14 is formed on a surface of the p-type conductive type semiconductor layer 5. The p-side transparent electrode 14 covers a substantially whole area of a predetermined current injection region 13 on a surface of the p-type conductive type semiconductor layer 5. A p-side electrode 15 is formed on a surface of the p-side transparent electrode layer 14.
    Type: Grant
    Filed: January 20, 2015
    Date of Patent: January 16, 2018
    Assignee: ROHM CO., LTD.
    Inventors: Takao Fujimori, Tomohito Kawase, Yasuo Nakanishi
  • Publication number: 20170352781
    Abstract: A semiconductor light emitting element is disclosed. The element includes a substrate including a first surface, a second surface opposite to the first surface, and a side surface that connects the first surface and the second surface; a semiconductor layer formed on the first surface of the substrate and configured to generate light; and a light reflective layer formed on the second surface of the substrate to cover an entire region of the second surface of the substrate and configured to reflect the light generated by the semiconductor layer toward the semiconductor layer. A modified layer, which has a physical property different from that of the other portion of the substrate, is formed on the side surface of the substrate to be spaced apart from the first surface toward the second surface by altering a material forming the substrate.
    Type: Application
    Filed: June 1, 2017
    Publication date: December 7, 2017
    Applicant: ROHM CO., LTD.
    Inventors: Hirotaka OBUCHI, Kazuaki TSUTSUMI, Hideaki ANZAI, Takao FUJIMORI
  • Publication number: 20170331004
    Abstract: A semiconductor light emitting device includes a substrate having a first major surface and a second major surface, a semiconductor layer that includes a first semiconductor layer of a first conductive type formed on the first major surface of the substrate, a light emitting layer formed on the first semiconductor layer and a second semiconductor layer of a second conductive type formed on the light emitting layer, and a mesa structure formed in the semiconductor layer by selectively notching the first semiconductor layer, the light emitting layer and the second semiconductor layer so as to expose the first semiconductor layer, and a ratio of a luminescent area of the light emitting layer with respect to an area of the first major surface of the substrate being set to equal to or smaller than 0.25.
    Type: Application
    Filed: May 4, 2017
    Publication date: November 16, 2017
    Applicant: ROHM CO., LTD.
    Inventors: Takao FUJIMORI, Kazuaki TSUTSUMI, Hirotaka OBUCHI
  • Publication number: 20170330994
    Abstract: A light-emitting element, a light-emitting element unit and a light-emitting element package are provided, which are each reduced in reflection loss and intra-film light absorption by suppressing multiple light reflection in a transparent electrode layer and hence have higher luminance. The light-emitting element 1 includes a substrate 2, an n-type nitride semiconductor layer 3, a light-emitting layer 4, a p-type nitride semiconductor layer 5, a transparent electrode layer 6 and a reflective electrode layer 7, and the transparent electrode layer 6 has a thickness T satisfying the following expression (1): 3 ? ? 4 ? n + 0.30 × ( ? 4 ? n ) ? T ? 3 ? ? 4 ? n + 0.45 × ( ? 4 ? n ) ( 1 ) wherein ? is the light-emitting wavelength of the light-emitting element 4, and n is the refractive index of the transparent electrode layer 6.
    Type: Application
    Filed: July 31, 2017
    Publication date: November 16, 2017
    Applicant: ROHM CO., LTD.
    Inventors: Takao FUJIMORI, Yasuo NAKANISHI
  • Patent number: 9755103
    Abstract: A light-emitting element, a light-emitting element unit and a light-emitting element package are provided, which are each reduced in reflection loss and intra-film light absorption by suppressing multiple light reflection in a transparent electrode layer and hence have higher luminance. The light-emitting element 1 includes a substrate 2, an n-type nitride semiconductor layer 3, a light-emitting layer 4, a p-type nitride semiconductor layer 5, a transparent electrode layer 6 and a reflective electrode layer 7, and the transparent electrode layer 6 has a thickness T satisfying the following expression (1): 3 ? ? 4 ? n + 0.30 × ( ? 4 ? n ) ? T ? 3 ? ? 4 ? n + 0.45 × ( ? 4 ? n ) ( 1 ) wherein ? is the light-emitting wavelength of the light-emitting element 4, and n is the refractive index of the transparent electrode layer 6.
    Type: Grant
    Filed: December 11, 2015
    Date of Patent: September 5, 2017
    Assignee: ROHM CO., LTD.
    Inventors: Takao Fujimori, Yasuo Nakanishi
  • Patent number: 9553239
    Abstract: A light emitting device includes a first conductive-type semiconductor layer laminated on a substrate; a light emitting layer laminated on the first conductive-type semiconductor layer; a second conductive-type semiconductor layer laminated on the light emitting layer; a first ITO layer laminated at a side of the first conductive-type semiconductor layer opposite to the substrate; a second ITO layer laminated at a side of the second conductive-type semiconductor layer opposite to the substrate; a first metal layer laminated on the first ITO layer; and a second metal layer laminated on the second ITO layer. The first and second metal layers have the same structure and each includes a lower metal layer which contacts a corresponding ITO layer of the first ITO layer and the second ITO layer; and an upper metal layer laminated on the lower metal layer, the upper metal layer being thicker than the lower metal layer.
    Type: Grant
    Filed: February 5, 2014
    Date of Patent: January 24, 2017
    Assignee: ROHM CO., LTD.
    Inventors: Takao Fujimori, Nobuaki Matsui
  • Publication number: 20160181489
    Abstract: A light emitting device includes a light emitting layer, a substrate that is transparent to an emission wavelength of the light emitting layer and positioned to receive an emission wavelength from the light emitting layer, a convex pattern including a collection of a plurality of convex portions discretely arranged on a front surface of the substrate with a first pitch, an n type nitride semiconductor layer located on the front surface of the substrate to cover the convex pattern and a p type nitride semiconductor layer located on the light emitting layer. The light emitting layer is located on the n type semiconductor layer. Each of the convex portions includes a sub convex pattern comprising a plurality of fine convex portions discretely formed at the top of the convex portion with a second pitch smaller than the first pitch, and a base supporting the sub convex pattern.
    Type: Application
    Filed: February 25, 2016
    Publication date: June 23, 2016
    Applicant: ROHM CO., LTD.
    Inventors: Nobuaki MATSUI, Hirotaka OBUCHI, Yasuo NAKANISHI, Kazuaki TSUTSUMI, Takao FUJIMORI
  • Publication number: 20160099377
    Abstract: A light-emitting element, a light-emitting element unit and a light-emitting element package are provided, which are each reduced in reflection loss and intra-film light absorption by suppressing multiple light reflection in a transparent electrode layer and hence have higher luminance. The light-emitting element 1 includes a substrate 2, an n-type nitride semiconductor layer 3, a light-emitting layer 4, a p-type nitride semiconductor layer 5, a transparent electrode layer 6 and a reflective electrode layer 7, and the transparent electrode layer 6 has a thickness T satisfying the following expression (1): 3 ? ? 4 ? n + 0.30 × ( ? 4 ? n ) ? T ? 3 ? ? 4 ? n + 0.45 × ( ? 4 ? n ) ( 1 ) wherein ? is the light-emitting wavelength of the light-emitting element 4, and n is the refractive index of the transparent electrode layer 6.
    Type: Application
    Filed: December 11, 2015
    Publication date: April 7, 2016
    Applicant: ROHM CO., LTD.
    Inventors: Takao FUJIMORI, Yasuo NAKANISHI
  • Patent number: 9281444
    Abstract: A light emitting device includes a light emitting layer, a substrate that is transparent to an emission wavelength of the light emitting layer and positioned to receive an emission wavelength from the light emitting layer, a convex pattern including a collection of a plurality of convex portions discretely arranged on a front surface of the substrate with a first pitch, an n type nitride semiconductor layer located on the front surface of the substrate to cover the convex pattern and a p type nitride semiconductor layer located on the light emitting layer. The light emitting layer is located on the n type semiconductor layer. Each of the convex portions includes a sub convex pattern comprising a plurality of fine convex portions discretely formed at the top of the convex portion with a second pitch smaller than the first pitch, and a base supporting the sub convex pattern.
    Type: Grant
    Filed: March 10, 2014
    Date of Patent: March 8, 2016
    Assignee: ROHM CO., LTD.
    Inventors: Nobuaki Matsui, Hirotaka Obuchi, Yasuo Nakanishi, Kazuaki Tsutsumi, Takao Fujimori
  • Patent number: 9231162
    Abstract: A light-emitting element, a light-emitting element unit and a light-emitting element package are provided, which are each reduced in reflection loss and intra-film light absorption by suppressing multiple light reflection in a transparent electrode layer and hence have higher luminance. The light-emitting element 1 includes a substrate 2, an n-type nitride semiconductor layer 3, a light-emitting layer 4, a p-type nitride semiconductor layer 5, a transparent electrode layer 6 and a reflective electrode layer 7, and the transparent electrode layer 6 has a thickness T satisfying the following expression (1): 3 ? ? 4 ? ? n + 0.30 × ( ? 4 ? ? n ) ? T ? 3 ? ? 4 ? ? n + 0.45 × ( ? 4 ? ? n ) ( 1 ) wherein ? is the light-emitting wavelength of the light-emitting element 4, and n is the refractive index of the transparent electrode layer 6.
    Type: Grant
    Filed: January 6, 2014
    Date of Patent: January 5, 2016
    Assignee: ROHM CO., LTD.
    Inventors: Takao Fujimori, Yasuo Nakanishi