Patents by Inventor Tsutomu KIYOSUMI

Tsutomu KIYOSUMI 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).

  • AlGaInP-based semiconductor laser
    Patent number: 10170891
    Abstract: An aluminium gallium indium phosphide (AlGaInP)-based semiconductor laser device is provided. On a main surface of a semiconductor substrate formed of n-type GaAs (gallium arsenide), from the bottom layer, an n-type buffer layer, an n-type cladding layer formed of an AlGaInP-based semiconductor containing silicon (Si) as a dopant, an active layer, a p-type cladding layer formed of an AlGaInP-based semiconductor containing magnesium (Mg) or zinc (Zn) as a dopant, an etching stopper layer, and a p-type contact layer are formed. Here, when an Al composition ratio x of the AlGaInP-based semiconductor is taken as a composition ratio of Al and Ga defined as (AlxGa1-x)0.5In0.5P, a composition of the n-type cladding layer is expressed as (AlxnGa1-xn)0.5In0.5P (0.9<xn<1) and a composition of the p-type cladding layer is expressed as (AlxpGa1-xp)0.5In0.5P (0.9<xp?1), and xn and xp satisfy a relationship of xn<xp.
    Type: Grant
    Filed: July 15, 2016
    Date of Patent: January 1, 2019
    Assignee: USHIO OPTO SEMICONDUCTORS, INC.
    Inventors: Masato Hagimoto, Haruki Fukai, Tsutomu Kiyosumi, Shinji Sasaki, Satoshi Kawanaka
  • AlGaInP-BASED SEMICONDUCTOR LASER
    Publication number: 20170012410
    Abstract: An aluminium gallium indium phosphide (AlGaInP)-based semiconductor laser device is provided. On a main surface of a semiconductor substrate formed of n-type GaAs (gallium arsenide), from the bottom layer, an n-type buffer layer, an n-type cladding layer formed of an AlGaInP-based semiconductor containing silicon (Si) as a dopant, an active layer, a p-type cladding layer formed of an AlGaInP-based semiconductor containing magnesium (Mg) or zinc (Zn) as a dopant, an etching stopper layer, and a p-type contact layer are formed. Here, when an Al composition ratio x of the AlGaInP-based semiconductor is taken as a composition ratio of Al and Ga defined as (AlxGa1-x)0.5In0.5P, a composition of the n-type cladding layer is expressed as (AlxnGa1-xn)0.5In0.5P (0.9<xn<1) and a composition of the p-type cladding layer is expressed as (AlxpGa1-xp)0.5In0.5P (0.9<xp?1), and xn and xp satisfy a relationship of xn<xp.
    Type: Application
    Filed: July 15, 2016
    Publication date: January 12, 2017
    Inventors: Masato HAGIMOTO, Haruki FUKAI, Tsutomu KIYOSUMI, Shinji SASAKI, Satoshi KAWANAKA
  • AlGaInP-based semiconductor laser
    Patent number: 9425583
    Abstract: An aluminium gallium indium phosphide (AlGaInP)-based semiconductor laser device is provided. On a main surface of a semiconductor substrate formed of n-type GaAs (gallium arsenide), from the bottom layer, an n-type buffer layer, an n-type cladding layer formed of an AlGaInP-based semiconductor containing silicon (Si) as a dopant, an active layer, a p-type cladding layer formed of an AlGaInP-based semiconductor containing magnesium (Mg) or zinc (Zn) as a dopant, an etching stopper layer, and a p-type contact layer are formed. Here, when an Al composition ratio x of the AlGaInP-based semiconductor is taken as a composition ratio of Al and Ga defined as (AlxGa1?x)0.5In0.5P, a composition of the n-type cladding layer is expressed as (AlxnGa1?xn)0.5In0.5P (0.9<xn<1) and a composition of the p-type cladding layer is expressed as (AlxpGa1?xp)0.5In0.5P (0.9<xp?1), and xn and xp satisfy a relationship of xn<xp.
    Type: Grant
    Filed: December 14, 2012
    Date of Patent: August 23, 2016
    Assignee: USHIO OPTO SEMICONDUCTORS, INC.
    Inventors: Masato Hagimoto, Haruki Fukai, Tsutomu Kiyosumi, Shinji Sasaki, Satoshi Kawanaka
  • SEMICONDUCTOR LASER
    Publication number: 20150003483
    Abstract: An aluminium gallium indium phosphide (AlGaInP)-based semiconductor laser device is provided. On a main surface of a semiconductor substrate formed of n-type GaAs (gallium arsenide), from the bottom layer, an n-type buffer layer, an n-type cladding layer formed of an AlGaInP-based semiconductor containing silicon (Si) as a dopant, an active layer, a p-type cladding layer formed of an AlGaInP-based semiconductor containing magnesium (Mg) or zinc (Zn) as a dopant, an etching stopper layer, and a p-type contact layer are formed. Here, when an Al composition ratio x of the AlGaInP-based semiconductor is taken as a composition ratio of Al and Ga defined as (AlxGa1-x)0.5In0.5P, a composition of the n-type cladding layer is expressed as (AlxGa1-x)0.5In0.5P (0.9<xn<1) and a composition of the p-type cladding layer is expressed as (AlxpGa1-xp)0.5In0.5P (0.9<xp?1), and xn and xp satisfy a relationship of xn<xp.
    Type: Application
    Filed: September 18, 2014
    Publication date: January 1, 2015
    Inventors: Masato HAGIMOTO, Haruki FUKAI, Tsutomu KIYOSUMI, Shinji SASAKI, Satoshi KAWANAKA