Patents by Inventor Takaaki Agui

Takaaki Agui 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: 20190035965
    Abstract: A Group III-V compound semiconductor solar cell includes a buffer layer (108) and a first cell (131) both between a first electrode (121) and a second electrode (102). The buffer layer (108) has a portion in which first segments (141a, 142a, 143a, 144a) and second segments (141b, 142b, 143b, 144b) are alternately provided. Each of the first segments has a Group III element composition that continuously changes with an increasing thickness of the buffer layer (108) as traced from a side located opposite where the first cell (131) is disposed toward a side where the first cell (131) is disposed. Each of the second segments has a Group III element composition that changes without an increase in the thickness of the buffer layer (108).
    Type: Application
    Filed: December 9, 2016
    Publication date: January 31, 2019
    Inventor: TAKAAKI AGUI
  • Patent number: 8933326
    Abstract: Disclosed is a multijunction compound semiconductor solar cell having a buffer layer between a first cell and a second cell. In the buffer layer, a plurality of semiconductor layers is arranged such that lattice constants thereof have larger values in order from the first cell side to the second cell side. Of the plurality of semiconductor layers, two layers having the largest difference in lattice constant among each two adjacent layers are disposed closer to the first cell than the center in the thickness direction of the buffer layer.
    Type: Grant
    Filed: December 27, 2010
    Date of Patent: January 13, 2015
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Kazuaki Sasaki, Takaaki Agui
  • Publication number: 20140060631
    Abstract: A compound semiconductor solar battery including a first compound semiconductor photoelectric conversion cell (40a), a second compound semiconductor photoelectric conversion cell (40b) provided on the first compound semiconductor photoelectric conversion cell (40a), and a compound semiconductor buffer layer (41) provided between the first compound semiconductor photoelectric conversion cell (40a) and the second compound semiconductor photoelectric conversion cell (40b), the first compound semiconductor photoelectric conversion cell (40a) and the compound semiconductor buffer layer (41) being provided adjacent to each other, and a ratio of a difference in lattice constant between the first compound semiconductor photoelectric conversion cell (40a) and a compound semiconductor layer (30) provided in a position closest to the first compound semiconductor photoelectric conversion cell (40a) among compound semiconductor layers constituting the compound semiconductor buffer layer (41) being not less than 0.
    Type: Application
    Filed: November 6, 2013
    Publication date: March 6, 2014
    Applicant: Sharp Kabushiki Kaisha
    Inventors: Takaaki AGUI, Tatsuya TAKAMOTO
  • Publication number: 20120247547
    Abstract: Disclosed is a multijunction compound semiconductor solar cell having a buffer layer between a first cell and a second cell. In the buffer layer, a plurality of semiconductor layers is arranged such that lattice constants thereof have larger values in order from the first cell side to the second cell side. Of the plurality of semiconductor layers, two layers having the largest difference in lattice constant among each two adjacent layers are disposed closer to the first cell than the center in the thickness direction of the buffer layer.
    Type: Application
    Filed: December 27, 2010
    Publication date: October 4, 2012
    Inventors: Kazuaki Sasaki, Takaaki Agui
  • Publication number: 20110290312
    Abstract: A compound semiconductor solar battery including a first compound semiconductor photoelectric conversion cell, a second compound semiconductor photoelectric conversion cell provided on the first compound semiconductor photoelectric conversion cell, and a compound semiconductor buffer layer provided between the first compound semiconductor photoelectric conversion cell and the second compound semiconductor photoelectric conversion cell, the first compound semiconductor photoelectric conversion cell and the compound semiconductor buffer layer being provided adjacent to each other, and a ratio of a difference in lattice constant between the first compound semiconductor photoelectric conversion cell and a compound semiconductor layer provided in a position closest to the first compound semiconductor photoelectric conversion cell among compound semiconductor layers constituting the compound semiconductor buffer layer being not less than 0.15% and not more than 0.
    Type: Application
    Filed: February 2, 2010
    Publication date: December 1, 2011
    Inventors: Takaaki Agui, Tatsuya Takamoto
  • Publication number: 20100279456
    Abstract: On a surface of a GaAs substrate, layers to be a top cell are formed by epitaxial growth. On the top cell, layers to be a bottom cell are formed. Thereafter, on a surface of the bottom cell, a back surface electrode is formed. Thereafter, a glass plate is adhered to the back surface electrode by wax. Then, the GaAs substrate supported by the glass plate is dipped in an alkali solution, whereby the GaAs substrate is removed. Thereafter, a surface electrode is formed on the top cell. Finally the glass plate is separated from the back surface electrode. In this manner, a compound solar battery that improves efficiency of conversion to electric energy can be obtained.
    Type: Application
    Filed: September 15, 2008
    Publication date: November 4, 2010
    Applicant: Sharp Kabushiki Kaisha
    Inventors: Tatsuya Takamoto, Takaaki Agui
  • Patent number: 7635638
    Abstract: A compound semiconductor device epitaxial growth substrate, wherein a semiconductor substrate, a substrate protective layer made of a material that is different from the material of the substrate, a middle layer for making separation of the semiconductor substrate and a compound semiconductor device layer possible, and a compound semiconductor device layer that is formed through epitaxial growth are layered in this order; and a semiconductor device which uses the compound semiconductor device layer that is gained by separating the semiconductor substrate, the substrate protective layer and the middle layer from this compound semiconductor device epitaxial growth substrate; as well as manufacturing methods for these.
    Type: Grant
    Filed: October 29, 2007
    Date of Patent: December 22, 2009
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Tatsuya Takamoto, Takaaki Agui
  • Patent number: 7488890
    Abstract: On a surface of a GaAs substrate, layers to be a top cell are formed by epitaxial growth. On the top cell, layers to be a bottom cell are formed. Thereafter, on a surface of the bottom cell, a back surface electrode is formed. Thereafter, a glass plate is adhered to the back surface electrode by wax. Then, the GaAs substrate supported by the glass plate is dipped in an alkali solution, whereby the GaAs substrate is removed. Thereafter, a surface electrode is formed on the top cell. Finally the glass plate is separated from the back surface electrode. In this manner, a compound solar battery that improves efficiency of conversion to electric energy can be obtained.
    Type: Grant
    Filed: March 22, 2004
    Date of Patent: February 10, 2009
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Tatsuya Takamoto, Takaaki Agui
  • Publication number: 20080070388
    Abstract: A compound semiconductor device epitaxial growth substrate, wherein a semiconductor substrate, a substrate protective layer made of a material that is different from the material of the substrate, a middle layer for making separation of the semiconductor substrate and a compound semiconductor device layer possible, and a compound semiconductor device layer that is formed through epitaxial growth are layered in this order; and a semiconductor device which uses the compound semiconductor device layer that is gained by separating the semiconductor substrate, the substrate protective layer and the middle layer from this compound semiconductor device epitaxial growth substrate; as well as manufacturing methods for these.
    Type: Application
    Filed: October 29, 2007
    Publication date: March 20, 2008
    Applicant: Sharp Kabushiki Kaisha
    Inventors: Tatsuya Takamoto, Takaaki Agui
  • Publication number: 20070199592
    Abstract: There are provided a solar cell string including a plurality of connected solar cells, each solar cell including a multilayered body having a photoelectric conversion layer, a first electrode formed on the multilayered body, a second electrode formed on the multilayered body, a first interconnector connected to the first electrode, and a second interconnector connected to the second electrode, wherein, in the solar cells adjacent to each other, the first interconnector connected to the first electrode of a first solar cell and the second interconnector connected to the second electrode of a second solar cell are connected via an intermediate member; and a solar cell module including the solar cell string.
    Type: Application
    Filed: February 15, 2007
    Publication date: August 30, 2007
    Applicant: Sharp Kabushiki Kaisha
    Inventors: Takaaki Agui, Naoki Takahashi
  • Publication number: 20060180198
    Abstract: A solar cell includes a first compound semiconductor stacked body with an n-type compound semiconductor layer and a p-type compound semiconductor layer in contact with each other, the first compound semiconductor stacked body has a first electrode of a first polarity and a second electrode of a second polarity, and surfaces of the first electrode and the second electrode are exposed to the same side. A solar cell string using the solar cells and a method of manufacturing the solar cell string are further provided.
    Type: Application
    Filed: February 10, 2006
    Publication date: August 17, 2006
    Applicant: Sharp Kabushiki Kaisha
    Inventors: Tatsuya Takamoto, Takaaki Agui, Hidetoshi Washio, Naoki Takahashi
  • Publication number: 20060054900
    Abstract: A compound semiconductor device epitaxial growth substrate, wherein a semiconductor substrate, a substrate protective layer made of a material that is different from the material of the substrate, a middle layer for making separation of the semiconductor substrate and a compound semiconductor device layer possible, and a compound semiconductor device layer that is formed through epitaxial growth are layered in this order; and a semiconductor device which uses the compound semiconductor device layer that is gained by separating the semiconductor substrate, the substrate protective layer and the middle layer from this compound semiconductor device epitaxial growth substrate; as well as manufacturing methods for these.
    Type: Application
    Filed: September 8, 2005
    Publication date: March 16, 2006
    Applicant: Sharp Kabushiki Kaisha
    Inventors: Tatsuya Takamoto, Takaaki Agui
  • Publication number: 20040206389
    Abstract: On a surface of a GaAs substrate, layers to be a top cell are formed by epitaxial growth. On the top cell, layers to be a bottom cell are formed. Thereafter, on a surface of the bottom cell, a back surface electrode is formed. Thereafter, a glass plate is adhered to the back surface electrode by wax. Then, the GaAs substrate supported by the glass plate is dipped in an alkali solution, whereby the GaAs substrate is removed. Thereafter, a surface electrode is formed on the top cell. Finally the glass plate is separated from the back surface electrode. In this manner, a compound solar battery that improves efficiency of conversion to electric energy can be obtained.
    Type: Application
    Filed: March 22, 2004
    Publication date: October 21, 2004
    Applicant: Sharp Kabushiki Kaisha
    Inventors: Tatsuya Takamoto, Takaaki Agui
  • Publication number: 20040187912
    Abstract: In an InGaP/InGaAs/Ge triple-junction solar cell, efficiency of a multijunction solar cell is improved by adjusting a ratio of an Al composition in an (Al)InGaP cell. According to a current-matching method in a multijunction solar cell, the ratio of the Al composition in an AlInGaP material for a top cell is adjusted in order to achieve matching between photocurrents generated in the top cell and a middle cell in the multijunction solar cell. Here, the multijunction solar cell uses as the top cell a solar cell-formed with the AlInGaP material and having a PN junction, uses as a middle cell a solar cell lattice-matched to the top cell, formed with an (In)GaAs(N) material and having a PN junction, and uses as a bottom cell a solar cell lattice-matched to the middle cell, formed with a Ge material and having a PN junction.
    Type: Application
    Filed: March 1, 2004
    Publication date: September 30, 2004
    Applicant: Sharp Kabushiki Kaisha
    Inventors: Tatsuya Takamoto, Takaaki Agui
  • Patent number: 6300558
    Abstract: A solar cell comprises at least a germanium (Ge) substrate, buffer layers formed on the germanium substrate, a first InxGa1-xAs layer of first conductivity type formed on the buffer layers, and a second InxGa1-xAs layer of second conductivity type formed on the first InxGa1-xAs layer to form pn junction. Because the composition x of In contained in the first InxGa1-xAs layer and the second InxGa1-xAs layer is in a range of 0.005≦x≦0.015, the inexpensive and high conversion efficiency solar cell can be achieved.
    Type: Grant
    Filed: April 20, 2000
    Date of Patent: October 9, 2001
    Assignee: Japan Energy Corporation
    Inventors: Tatsuya Takamoto, Hiroshi Kurita, Takaaki Agui, Eiji Ikeda
  • Patent number: 5916375
    Abstract: The present invention is directed to a method of manufacturing a photovoltaic cell with high conversion efficiency, wherein a polycrystal CdTe layer with a large grain size can be formed by forming an indium oxide film (20) on a transparent conductive substrate having a transparent conductive film (2) as its surface layer, then forming an n-type CdS layer (3) and a p-type CdTe layer (4) thereon, then attaching cadmium chloride (CdCl.sub.2) on the p-type CdTe layer, and then annealing. The indium oxide film (20) is capable of relaxing strain caused at an interface between the transparent conductive film (2) and the n-type CdS layer (3), so that a good CdS/CdTe junction interface can be formed. The indium oxide film (20) can be formed by forming an indium film on the transparent conductive substrate and then annealing in oxygen containing atmosphere.
    Type: Grant
    Filed: April 6, 1998
    Date of Patent: June 29, 1999
    Assignee: Japan Energy Corporation
    Inventors: Takaaki Agui, Tatsuya Takamoto