Patents by Inventor Takayuki Kawasumi

Takayuki Kawasumi 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).

  • Patent number: 11923661
    Abstract: A method of manufacturing a surface emitting laser according to an embodiment of the present disclosure includes the following two steps: (1) a step of forming a semiconductor stacked structure on a substrate, the semiconductor stacked structure including an active layer, a first DBR layer of a first electrical conduction type, and a second DBR layer of a second electrical conduction type, the first DBR layer and the second DBR layer sandwiching the active layer, the second electrical conduction type being different from the first electrical conduction type; and (2) a step of forming a mesa section at a portion on the second DBR layer side in the semiconductor stacked structure and then forming an annular diffusion region of the first electrical conduction type at an outer edge of the mesa section by impurity diffusion from a side surface of the mesa section, the mesa section including the second DBR layer, the mesa section not including the active layer.
    Type: Grant
    Filed: June 14, 2019
    Date of Patent: March 5, 2024
    Assignee: Sony Semiconductor Solutions Corporation
    Inventors: Takayuki Kawasumi, Hideki Kimura, Kota Tokuda, Yoshiaki Watanabe
  • Publication number: 20230246420
    Abstract: A surface-emitting semiconductor laser includes a substrate, a first electrode in contact with the substrate, a first light reflection layer over the substrate, a second light reflection layer over the substrate, with the first light reflection layer between the second light reflection layer and the substrate, an active layer between the second light reflection layer and the first light reflection layer, a current confining layer between the active layer and the second light reflection layer and includes a current injection region, a second electrode over the substrate, with the second light reflection layer between the second electrode and the substrate, at least a portion of the second electrode is at a position overlapping the current injection region, and a contact layer between the second electrode and the second light reflection layer and includes a contact region in contact with the second electrode.
    Type: Application
    Filed: March 29, 2023
    Publication date: August 3, 2023
    Inventors: YOSHIAKI WATANABE, TAKAYUKI KAWASUMI
  • Patent number: 11652333
    Abstract: A surface-emitting semiconductor laser includes a substrate, a first electrode provided in contact with the substrate, a first light reflection layer provided over the substrate, a second light reflection layer provided over the substrate, an active layer provided between the second light reflection layer and the first light reflection layer, a current confining layer that is provided between the active layer and the second light reflection layer and includes a current injection region, a second electrode provided over the substrate, with the second light reflection layer being interposed between the second electrode and the substrate, and a contact layer that is provided between the second electrode and the second light reflection layer and includes a contact region that is in contact with the second electrode, in which the contact region has a smaller area than an area of the current injection region.
    Type: Grant
    Filed: November 22, 2018
    Date of Patent: May 16, 2023
    Assignee: SONY SEMICONDUCTOR SOLUTIONS CORPORATION
    Inventors: Yoshiaki Watanabe, Takayuki Kawasumi
  • Patent number: 11271368
    Abstract: A semiconductor laser according to one embodiment of the present disclosure includes a semiconductor stack. The semiconductor stack includes, in the following order, a first cladding layer, an active layer, one or a plurality of low-concentration impurity layers, a contact layer, and a second cladding layer that includes a transparent conductive material. The semiconductor stack further has, in a portion including the contact layer, a ridge extending in a stacked in-plane direction. Each low-concentration impurity layer has an impurity concentration of 5.0×1017 cm?3 or less, and a total thickness of the low-concentration impurity layer is 250 nm or more and 1000 nm or less. A distance between the second cladding layer and the low-concentration impurity layer closest to the second cladding layer is 150 nm or less.
    Type: Grant
    Filed: January 17, 2019
    Date of Patent: March 8, 2022
    Assignee: SONY SEMICONDUCTOR SOLUTIONS CORPORATION
    Inventors: Kota Tokuda, Hideki Watanabe, Takayuki Kawasumi
  • Publication number: 20210328408
    Abstract: A method of manufacturing a surface emitting laser according to an embodiment of the present disclosure includes the following two steps: (1) a step of forming a semiconductor stacked structure on a substrate, the semiconductor stacked structure including an active layer, a first DBR layer of a first electrical conduction type, and a second DBR layer of a second electrical conduction type, the first DBR layer and the second DBR layer sandwiching the active layer, the second electrical conduction type being different from the first electrical conduction type; and (2) a step of forming a mesa section at a portion on the second DBR layer side in the semiconductor stacked structure and then forming an annular diffusion region of the first electrical conduction type at an outer edge of the mesa section by impurity diffusion from a side surface of the mesa section, the mesa section including the second DBR layer, the mesa section not including the active layer.
    Type: Application
    Filed: June 14, 2019
    Publication date: October 21, 2021
    Inventors: Takayuki KAWASUMI, Hideki KIMURA, Kota TOKUDA, Yoshiaki WATANABE
  • Publication number: 20210265819
    Abstract: A surface-emitting semiconductor laser includes: a substrate; a first electrode provided in contact with the substrate; a first light reflection layer provided over the substrate; a second light reflection layer provided over the substrate, with the first light reflection layer being interposed between the second light reflection layer and the substrate; an active layer provided between the second light reflection layer and the first light reflection layer; a current confining layer that is provided between the active layer and the second light reflection layer and includes a current injection region; a second electrode provided over the substrate, with the second light reflection layer being interposed between the second electrode and the substrate, at least a portion of the second electrode being provided at a position overlapping the current injection region; and a contact layer that is provided between the second electrode and the second light reflection layer and includes a contact region that is in cont
    Type: Application
    Filed: November 22, 2018
    Publication date: August 26, 2021
    Inventors: YOSHIAKI WATANABE, TAKAYUKI KAWASUMI
  • Publication number: 20210066887
    Abstract: A semiconductor laser according to one embodiment of the present disclosure includes a semiconductor stack. The semiconductor stack includes, in the following order, a first cladding layer, an active layer, one or a plurality of low-concentration impurity layers, a contact layer, and a second cladding layer that includes a transparent conductive material. The semiconductor stack further has, in a portion including the contact layer, a ridge extending in a stacked in-plane direction. Each low-concentration impurity layer has an impurity concentration of 5.0×1017 cm?3 or less, and a total thickness of the low-concentration impurity layer is 250 nm or more and 1000 nm or less. A distance between the second cladding layer and the low-concentration impurity layer closest to the second cladding layer is 150 nm or less.
    Type: Application
    Filed: January 17, 2019
    Publication date: March 4, 2021
    Inventors: KOTA TOKUDA, HIDEKI WATANABE, TAKAYUKI KAWASUMI
  • Publication number: 20200381898
    Abstract: A semiconductor light-emitting device includes a layer structure of a nitride semiconductor, and the layer structure includes an n-type semiconductor layer, a p-type semiconductor layer, and an intermediate layer. The intermediate layer includes an active layer and is provided between the n-type semiconductor layer and the p-type semiconductor layer. The layer structure includes a residual donor in a region at least included in the intermediate layer, the region being situated between the active layer and the p-type semiconductor layer. The intermediate layer includes impurities in the region between the active layer and the p-type semiconductor layer, the impurities compensating the residual donor. Further, the intermediate layer is configured such that a concentration of the impurities in the region between the active layer and the p-type semiconductor layer is higher than a concentration of the impurities in the p-type semiconductor layer.
    Type: Application
    Filed: September 27, 2018
    Publication date: December 3, 2020
    Inventors: TAKAYUKI KAWASUMI, KOTA TOKUDA
  • Patent number: 10672944
    Abstract: A semiconductor light emitting element includes a first conductive layer, a second conductive layer, and an active layer provided between the first conductive layer and the second conductive layer. The first conductive layer has a current constriction structure, a current injection region being constricted in the current constriction structure. The active layer includes a plurality of quantum well layers, a first light emission wavelength being in a wavelength range of an intensity peak of an entire light emission spectrum, the first light emission wavelength corresponding to a light emission recombination level energy gap of a first quantum well layer of the plurality of quantum well layers, the first quantum well layer being provided at a position closest to the current constriction structure.
    Type: Grant
    Filed: October 1, 2015
    Date of Patent: June 2, 2020
    Assignee: SONY CORPORATION
    Inventors: Yoshiaki Watanabe, Takayuki Kawasumi
  • Patent number: 10540916
    Abstract: A semiconductor light-emitting device according to an embodiment of the present disclosure includes an n-type semiconductor layer, a p-type semiconductor layer, and an active layer provided between the n-type semiconductor layer and the p-type semiconductor layer and including a plurality of well layers. In the plurality of well layers included in the active layer, a band gap inclination angle ?1 of a second well layer located relatively close to the p-type semiconductor layer is smaller than a band gap inclination angle ?2 of a first well layer located relatively close to the n-type semiconductor layer.
    Type: Grant
    Filed: December 27, 2016
    Date of Patent: January 21, 2020
    Assignee: SONY CORPORATION
    Inventors: Kota Tokuda, Takayuki Kawasumi
  • Patent number: 10541511
    Abstract: A semiconductor light-emitting element includes a laminated structure which has an active layer between a first conductivity-type semiconductor layer and a second conductivity-type semiconductor layer, a first semiconductor layer which includes at least the first conductivity-type semiconductor layer of the laminated structure, an insulation film which is formed on the first semiconductor layer and has an opening, and a second semiconductor layer which is formed on the insulation film and includes at least the second conductivity-type semiconductor layer of the laminated structure. The second semiconductor layer includes a first region facing the opening of the insulation film and a second region not facing the opening, and the second region has a portion with a higher impurity concentration than the first region.
    Type: Grant
    Filed: March 8, 2019
    Date of Patent: January 21, 2020
    Assignee: Sony Corporation
    Inventors: Kota Tokuda, Takayuki Kawasumi
  • Patent number: 10490692
    Abstract: There is provided a semiconductor light-emitting device including a light-emitting edge, an opposite edge, and a first conductive layer that includes a current narrowing structure having a longitudinal direction along one direction from the opposite edge to the light-emitting edge. An active layer is between the first conductive layer and a second conductive layer which respectively come into contact with the first conductive layer and the second conductive layer. The current narrowing structure includes a spread area such that a width of the spread area in a direction along a surface of the first conductive layer widens from a predetermined position toward the light-emitting edge in the one direction. The first electrode layer includes an electrode area on at least the spread area such that a width thereof in the direction along the surface of the first conductive layer becomes smaller than the width of the spread area.
    Type: Grant
    Filed: December 25, 2015
    Date of Patent: November 26, 2019
    Assignee: SONY CORPORATION
    Inventors: Yoshiaki Watanabe, Takayuki Kawasumi
  • Publication number: 20190207365
    Abstract: A semiconductor light-emitting element includes a laminated structure which has an active layer between a first conductivity-type semiconductor layer and a second conductivity-type semiconductor layer, a first semiconductor layer which includes at least the first conductivity-type semiconductor layer of the laminated structure, an insulation film which is formed on the first semiconductor layer and has an opening, and a second semiconductor layer which is formed on the insulation film and includes at least the second conductivity-type semiconductor layer of the laminated structure. The second semiconductor layer includes a first region facing the opening of the insulation film and a second region not facing the opening, and the second region has a portion with a higher impurity concentration than the first region.
    Type: Application
    Filed: March 8, 2019
    Publication date: July 4, 2019
    Inventors: Kota Tokuda, Takayuki Kawasumi
  • Patent number: 10320146
    Abstract: A semiconductor light-emitting element includes a laminated structure which has an active layer between a first conductivity-type semiconductor layer and a second conductivity-type semiconductor layer, a first semiconductor layer which includes at least the first conductivity-type semiconductor layer of the laminated structure, an insulation film which is formed on the first semiconductor layer and has an opening, and a second semiconductor layer which is formed on the insulation film and includes at least the second conductivity-type semiconductor layer of the laminated structure. The second semiconductor layer includes a first region facing the opening of the insulation film and a second region not facing the opening, and the second region has a portion with a higher impurity concentration than the first region.
    Type: Grant
    Filed: February 27, 2015
    Date of Patent: June 11, 2019
    Assignee: Sony Corporation
    Inventors: Kota Tokuda, Takayuki Kawasumi
  • Publication number: 20190005858
    Abstract: A semiconductor light-emitting device according to an embodiment of the present disclosure includes an n-type semiconductor layer, a p-type semiconductor layer, and an active layer provided between the n-type semiconductor layer and the p-type semiconductor layer and including a plurality of well layers. In the plurality of well layers included in the active layer, a band gap inclination angle ?1 of a second well layer located relatively close to the p-type semiconductor layer is smaller than a band gap inclination angle ?2 of a first well layer located relatively close to the n-type semiconductor layer.
    Type: Application
    Filed: December 27, 2016
    Publication date: January 3, 2019
    Inventors: KOTA TOKUDA, TAKAYUKI KAWASUMI
  • Patent number: 9966500
    Abstract: A semiconductor optical device includes: a ridge stripe structure portion 20 in which a first compound semiconductor layer 31, an active layer 32, and a second compound semiconductor layer 32 are stacked and which has a first end surface 21 which emits light and a second end surface 22 opposite to the first end surface 21; and a current regulation region 41 provided to be adjacent to at least one of ridge stripe adjacent portions 40 positioned at both sides of the ridge stripe structure portion 20, at the second end surface side, and to be away from the ridge stripe structure portion 20. A bottom surface of the current regulation region 41 is under the active layer 33, and a top surface of the ridge stripe adjacent portion 40 excluding the current regulation region 41 is above the active layer 33.
    Type: Grant
    Filed: March 20, 2015
    Date of Patent: May 8, 2018
    Assignee: SONY CORPORATION
    Inventors: Yoshiaki Watanabe, Takayuki Kawasumi
  • Publication number: 20180033910
    Abstract: [Solving Means] A first conductive layer of a semiconductor light-emitting device including a light-emitting edge and an opposite edge includes a current narrowing structure configured such that a current injection area is narrowed. A longitudinal direction of the current narrowing structure is provided along one direction from the opposite edge to the light-emitting edge. An active layer is provided between the first conductive layer and a second conductive layer. A first electrode layer and a second electrode layer respectively come into contact with the first conductive layer and the second conductive layer. The current narrowing structure includes a spread area. The spread area is provided such that a width of the current narrowing structure in a direction along a surface of the first conductive layer widens from a predetermined position toward the light-emitting edge in the one direction. The first electrode layer includes an electrode area.
    Type: Application
    Filed: December 25, 2015
    Publication date: February 1, 2018
    Applicant: SONY CORPORATION
    Inventors: YOSHIAKI WATANABE, TAKAYUKI KAWASUMI
  • Publication number: 20170288090
    Abstract: [Solving Means] A semiconductor light emitting element includes a first conductive layer, a second conductive layer, and an active layer provided between the first conductive layer and the second conductive layer. The first conductive layer has a current constriction structure, a current injection region being constricted in the current constriction structure. The active layer includes a plurality of quantum well layers, a first light emission wavelength being in a wavelength range of an intensity peak of an entire light emission spectrum, the first light emission wavelength corresponding to a light emission recombination level energy gap of a first quantum well layer of the plurality of quantum well layers, the first quantum well layer being provided at a position closest to the current constriction structure.
    Type: Application
    Filed: October 1, 2015
    Publication date: October 5, 2017
    Inventors: YOSHIAKI WATANABE, TAKAYUKI KAWASUMI
  • Publication number: 20170047480
    Abstract: A semiconductor optical device includes: a ridge stripe structure portion 20 in which a first compound semiconductor layer 31, an active layer 32, and a second compound semiconductor layer 32 are stacked and which has a first end surface 21 which emits light and a second end surface 22 opposite to the first end surface 21; and a current regulation region 41 provided to be adjacent to at least one of ridge stripe adjacent portions 40 positioned at both sides of the ridge stripe structure portion 20, at the second end surface side, and to be away from the ridge stripe structure portion 20. A bottom surface of the current regulation region 41 is under the active layer 33, and a top surface of the ridge stripe adjacent portion 40 excluding the current regulation region 41 is above the active layer 33.
    Type: Application
    Filed: March 20, 2015
    Publication date: February 16, 2017
    Inventors: YOSHIAKI WATANABE, TAKAYUKI KAWASUMI
  • Patent number: 9368685
    Abstract: A semiconductor light emitting device including an active layer, a compound semiconductor layer on the active layer, a contact layer on the compound semiconductor layer, and an electrode on the contact layer, where the contact layer is substantially the same size as the electrode.
    Type: Grant
    Filed: June 4, 2013
    Date of Patent: June 14, 2016
    Assignee: SONY CORPORATION
    Inventors: Hiroki Naito, Takahiro Koyama, Kensuke Kojima, Arata Kobayashi, Hiroyuki Okuyama, Makoto Oogane, Takayuki Kawasumi