Patents by Inventor Teruyoshi Takakura

Teruyoshi Takakura 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: 11128105
    Abstract: In a semiconductor laser device, a semiconductor layer includes a first groove formed on both sides of a ridge, a pair of second recesses facing each other and between which the ridge is interposed on a side of a light emitting surface, and a pair of third grooves in parallel to the first groove from the light emitting surface and interposing the ridge therebetween.
    Type: Grant
    Filed: January 22, 2020
    Date of Patent: September 21, 2021
    Assignee: SHARP KABUSHIKI KAISHA
    Inventors: Teruyoshi Takakura, Yoshimi Tanimoto, Yoshihiko Tani, Yuhzoh Tsuda
  • Publication number: 20200251885
    Abstract: In a semiconductor laser device, a semiconductor layer includes a first groove formed on both sides of a ridge, a pair of second recesses facing each other and between which the ridge is interposed on a side of a light emitting surface, and a pair of third grooves in parallel to the first groove from the light emitting surface and interposing the ridge therebetween.
    Type: Application
    Filed: January 22, 2020
    Publication date: August 6, 2020
    Inventors: TERUYOSHI TAKAKURA, YOSHIMI TANIMOTO, YOSHIHIKO TANI, YUHZOH TSUDA
  • Publication number: 20120049328
    Abstract: The present invention includes a first step of forming a nitride semiconductor layer by metal organic chemical vapor deposition by using a first carrier gas containing a nitrogen carrier gas and a hydrogen carrier gas of a flow quantity larger than that of the nitrogen carrier gas to thereby supply a raw material containing Mg and a Group V raw material containing N, and a second step of lowering a temperature by using a second carrier gas to which a material containing N is added, and hence solves the problems encountered in the art.
    Type: Application
    Filed: November 4, 2011
    Publication date: March 1, 2012
    Inventors: Yuhzoh Tsuda, Shigetoshi Ito, Mototaka Taneya, Yoshihiro Ueta, Teruyoshi Takakura
  • Patent number: 8076165
    Abstract: The present invention includes a first step of forming a nitride semiconductor layer by metal organic chemical vapor deposition by using a first carrier gas containing a nitrogen carrier gas and a hydrogen carrier gas of a flow quantity larger than that of the nitrogen carrier gas to thereby supply a raw material containing Mg and a Group V raw material containing N, and a second step of lowering a temperature by using a second carrier gas to which a material containing N is added, and hence solves the problems.
    Type: Grant
    Filed: March 2, 2006
    Date of Patent: December 13, 2011
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Yuhzoh Tsuda, Shigetoshi Ito, Mototaka Taneya, Yoshihiro Ueta, Teruyoshi Takakura
  • Patent number: 7858992
    Abstract: A nitride semiconductor laser device has a nitride semiconductor substrate that includes a dislocation-concentrated region 102 and a wide low-dislocation region and that has the top surface thereof slanted at an angle in the range of 0.3° to 0.7° relative to the C plane and a nitride semiconductor layer laid on top thereof. The nitride semiconductor layer has a depression immediately above the dislocation-concentrated region, and has, in a region thereof other than the depression, a high-quality quantum well active layer with good flatness and without cracks, a layer that, as is grown, readily exhibits p-type conductivity, and a stripe-shaped laser light waveguide region. The laser light waveguide region is formed above the low-dislocation region. This helps realize a nitride semiconductor laser device that offers a longer life.
    Type: Grant
    Filed: February 5, 2009
    Date of Patent: December 28, 2010
    Assignees: Sharp Kabushiki Kaisha, Sumitomo Electric Industries, Ltd.
    Inventors: Yoshihiro Ueta, Teruyoshi Takakura, Takeshi Kamikawa, Yuhzoh Tsuda, Shigetoshi Ito, Takayuki Yuasa, Mototaka Taneya, Kensaku Motoki
  • Patent number: 7700963
    Abstract: In a method for producing a nitride semiconductor light-emitting device according to the present invention, first, a nitride semiconductor substrate having groove portions formed is prepared. An underlying layer comprising nitride semiconductor is formed on the nitride semiconductor substrate including the side walls of the groove portions, in such a manner that the underlying layer has a crystal surface in each of the groove portions and the crystal surface is tilted at an angle of from 53.5° to 63.4° with respect to the surface of the substrate. Over the underlying layer, a light-emitting-device structure composed of a lower cladding layer containing Al, an active layer, and an upper cladding layer containing Al is formed. According to the present invention, thickness nonuniformity and lack of surface flatness, which occur when accumulating a layer with light-emitting-device structure of nitride semiconductor over the nitride semiconductor substrate, are alleviated while inhibiting occurrence of cracking.
    Type: Grant
    Filed: July 7, 2008
    Date of Patent: April 20, 2010
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Teruyoshi Takakura, Shigetoshi Ito, Takeshi Kamikawa
  • Publication number: 20100002738
    Abstract: It is intended to improve operation characteristics of a nitride-based semiconductor light-emitting device including a nitride-based semiconductor crystal substrate having a main surface of a non-polarity plane. A nitride-based semiconductor light-emitting device includes a nitride-based semiconductor crystal substrate and semiconductor stacked-layer structure of crystalline nitride-based semiconductor formed on a main surface of the substrate, wherein the semiconductor staked-layer structure includes an active layer sandwiched between an n-type layer and a p-type layer, the main surface of the substrate has a crystallographic plane tilted from a {10-10} plane of the nitride-based semiconductor crystal by an angle of more than ?0.5° and less than ?0.05° or more than +0.05° and less than +0.5° about a <0001> axis.
    Type: Application
    Filed: July 1, 2009
    Publication date: January 7, 2010
    Inventors: Teruyoshi Takakura, Yuhzoh Tsuda, Masataka Ohta
  • Publication number: 20090236585
    Abstract: A nitride semiconductor laser device has a nitride semiconductor substrate that includes a dislocation-concentrated region 102 and a wide low-dislocation region and that has the top surface thereof slanted at an angle in the range of 0.3° to 0.7° relative to the C plane and a nitride semiconductor layer laid on top thereof. The nitride semiconductor layer has a depression immediately above the dislocation-concentrated region, and has, in a region thereof other than the depression, a high-quality quantum well active layer with good flatness and without cracks, a layer that, as is grown, readily exhibits p-type conductivity, and a stripe-shaped laser light waveguide region. The laser light waveguide region is formed above the low-dislocation region. This helps realize a nitride semiconductor laser device that offers a longer life.
    Type: Application
    Filed: February 5, 2009
    Publication date: September 24, 2009
    Applicants: Sharp Kabushiki Kaisha, Sumitomo Electric Industries, Ltd.
    Inventors: Yoshihiro Ueta, Teruyoshi Takakura, Takeshi Kamikawa, Yuhzoh Tsuda, Shigetoshi Ito, Takayuki Yuasa, Mototaka Taneya, Kensaku Motoki
  • Patent number: 7579627
    Abstract: A nitride semiconductor laser device has a nitride semiconductor substrate that includes a dislocation-concentrated region 102 and a wide low-dislocation region and that has the top surface thereof slanted at an angle in the range of 0.3° to 0.7° relative to the C plane and a nitride semiconductor layer laid on top thereof. The nitride semiconductor layer has a depression immediately above the dislocation-concentrated region, and has, in a region thereof other than the depression, a high-quality quantum well active layer with good flatness and without cracks, a layer that, as is grown, readily exhibits p-type conductivity, and a stripe-shaped laser light waveguide region. The laser light waveguide region is formed above the low-dislocation region. This helps realize a nitride semiconductor laser device that offers a longer life.
    Type: Grant
    Filed: May 18, 2006
    Date of Patent: August 25, 2009
    Assignees: Sharp Kabushiki Kaisha, Sumitomo Electric Industries, Ltd.
    Inventors: Yoshihiro Ueta, Teruyoshi Takakura, Takeshi Kamikawa, Yuhzoh Tsuda, Shigetoshi Ito, Takayuki Yuasa, Mototaka Taneya, Kensaku Motoki
  • Publication number: 20090121320
    Abstract: The present invention includes a first step of forming a nitride semiconductor layer by metal organic chemical vapor deposition by using a first carrier gas containing a nitrogen carrier gas and a hydrogen carrier gas of a flow quantity larger than that of the nitrogen carrier gas to thereby supply a raw material containing Mg and a Group V raw material containing N, and a second step of lowering a temperature by using a second carrier gas to which a material containing N is added, and hence solves the problems.
    Type: Application
    Filed: March 2, 2006
    Publication date: May 14, 2009
    Inventors: Yuhzoh Tsuda, Shigetoshi Ito, Mototaka Taneya, Yoshihiro Ueta, Teruyoshi Takakura
  • Patent number: 7462882
    Abstract: A nitride semiconductor laser device has a nitride semiconductor substrate that includes a dislocation-concentrated region 102 and a wide low-dislocation region and that has the top surface thereof slanted at an angle in the range of 0.3° to 0.7° relative to the C plane and a nitride semiconductor layer laid on top thereof. The nitride semiconductor layer has a depression immediately above the dislocation-concentrated region, and has, in a region thereof other than the depression, a high-quality quantum well active layer with good flatness and without cracks, a layer that, as is grown, readily exhibits p-type conductivity, and a stripe-shaped laser light waveguide region. The laser light waveguide region is formed above the low-dislocation region. This helps realize a nitride semiconductor laser device that offers a longer life.
    Type: Grant
    Filed: April 26, 2004
    Date of Patent: December 9, 2008
    Assignees: Sharp Kabushiki Kaisha, Sumitomo Electric Industries, Ltd.
    Inventors: Yoshihiro Ueta, Teruyoshi Takakura, Takeshi Kamikawa, Yuhzoh Tsuda, Shigetoshi Ito, Takayuki Yuasa, Mototaka Taneya, Kensaku Motoki
  • Publication number: 20080283866
    Abstract: In a method for producing a nitride semiconductor light-emitting device according to the present invention, first, a nitride semiconductor substrate having groove portions formed is prepared. An underlying layer comprising nitride semiconductor is formed on the nitride semiconductor substrate including the side walls of the groove portions, in such a manner that the underlying layer has a crystal surface in each of the groove portions and the crystal surface is tilted at an angle of from 53.5° to 63.4° with respect to the surface of the substrate. Over the underlying layer, a light-emitting-device structure composed of a lower cladding layer containing Al, an active layer, and an upper cladding layer containing Al is formed. According to the present invention, thickness nonuniformity and lack of surface flatness, which occur when accumulating a layer with light-emitting-device structure of nitride semiconductor over the nitride semiconductor substrate, are alleviated while inhibiting occurrence of cracking.
    Type: Application
    Filed: July 7, 2008
    Publication date: November 20, 2008
    Inventors: Teruyoshi Takakura, Shigetoshi Ito, Takeshi Kamikawa
  • Patent number: 7410819
    Abstract: In a method for producing a nitride semiconductor light-emitting device according to the present invention, first, a nitride semiconductor substrate having groove portions formed is prepared. An underlying layer comprising nitride semiconductor is formed on the nitride semiconductor substrate including the side walls of the groove portions, in such a manner that the underlying layer has a crystal surface in each of the groove portions and the crystal surface is tilted at an angle of from 53.5° to 63.4° with respect to the surface of the substrate. Over the underlying layer, a light-emitting-device structure composed of a lower cladding layer containing Al, an active layer, and an upper cladding layer containing Al is formed. According to the present invention, thickness nonuniformity and lack of surface flatness, which occur when accumulating a layer with light-emitting-device structure of nitride semiconductor over the nitride semiconductor substrate, are alleviated while inhibiting occurrence of cracking.
    Type: Grant
    Filed: December 8, 2005
    Date of Patent: August 12, 2008
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Teruyoshi Takakura, Shigetoshi Ito, Takeshi Kamikawa
  • Patent number: 7109049
    Abstract: Provided is a method for fabricating a nitride semiconductor light-emitting device including a nitride semiconductor substrate having a groove and a ridge formed on the top surface thereof so as to extend in the shape of stripes and a nitride semiconductor growth layer consisting of a plurality of nitride semiconductor layers laid on top of the nitride semiconductor substrate. The method involves a step of forming a 10 ?m or more wide flat region above at least either of the groove and ridge by forming the nitride semiconductor growth layer on top of the nitride semiconductor substrate so that the height of the nitride semiconductor growth layer laid above the groove is smaller than the height of the nitride semiconductor growth layer laid above the ridge.
    Type: Grant
    Filed: February 17, 2005
    Date of Patent: September 19, 2006
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Teruyoshi Takakura, Takeshi Kamikawa, Yoshika Kaneko
  • Publication number: 20060202188
    Abstract: A nitride semiconductor laser device has a nitride semiconductor substrate that includes a dislocation-concentrated region 102 and a wide low-dislocation region and that has the top surface thereof slanted at an angle in the range of 0.3° to 0.7° relative to the C plane and a nitride semiconductor layer laid on top thereof. The nitride semiconductor layer has a depression immediately above the dislocation-concentrated region, and has, in a region thereof other than the depression, a high-quality quantum well active layer with good flatness and without cracks, a layer that, as is grown, readily exhibits p-type conductivity, and a stripe-shaped laser light waveguide region. The laser light waveguide region is formed above the low-dislocation region. This helps realize a nitride semiconductor laser device that offers a longer life.
    Type: Application
    Filed: May 18, 2006
    Publication date: September 14, 2006
    Applicants: SHARP KABUSHIKI KAISHA, SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Yoshihiro Ueta, Teruyoshi Takakura, Takeshi Kamikawa, Yuhzoh Tsuda, Shigetoshi Ito, Takayuki Yuasa, Mototaka Taneya, Kensaku Motoki
  • Publication number: 20060131590
    Abstract: In a method for producing a nitride semiconductor light-emitting device according to the present invention, first, a nitride semiconductor substrate having groove portions formed is prepared. An underlying layer comprising nitride semiconductor is formed on the nitride semiconductor substrate including the side walls of the groove portions, in such a manner that the underlying layer has a crystal surface in each of the groove portions and the crystal surface is tilted at an angle of from 53.5° to 63.4° with respect to the surface of the substrate. Over the underlying layer, a light-emitting-device structure composed of a lower cladding layer containing Al, an active layer, and an upper cladding layer containing Al is formed. According to the present invention, thickness nonuniformity and lack of surface flatness, which occur when accumulating a layer with light-emitting-device structure of nitride semiconductor over the nitride semiconductor substrate, are alleviated while inhibiting occurrence of cracking.
    Type: Application
    Filed: December 8, 2005
    Publication date: June 22, 2006
    Inventors: Teruyoshi Takakura, Shigetoshi Ito, Takeshi Kamikawa
  • Publication number: 20050186694
    Abstract: Provided is a method for fabricating a nitride semiconductor light-emitting device including a nitride semiconductor substrate having a groove and a ridge formed on the top surface thereof so as to extend in the shape of stripes and a nitride semiconductor growth layer consisting of a plurality of nitride semiconductor layers laid on top of the nitride semiconductor substrate. The method involves a step of forming a 10 ?m or more wide flat region above at least either of the groove and ridge by forming the nitride semiconductor growth layer on top of the nitride semiconductor substrate so that the height of the nitride semiconductor growth layer laid above the groove is smaller than the height of the nitride semiconductor growth layer laid above the ridge.
    Type: Application
    Filed: February 17, 2005
    Publication date: August 25, 2005
    Applicant: Sharp Kabushiki Kaisha
    Inventors: Teruyoshi Takakura, Takeshi Kamikawa, Yoshika Kaneko
  • Publication number: 20050141577
    Abstract: A nitride semiconductor laser device has a nitride semiconductor substrate that includes a dislocation-concentrated region 102 and a wide low-dislocation region and that has the top surface thereof slanted at an angle in the range of 0.3° to 0.7° relative to the C plane and a nitride semiconductor layer laid on top thereof. The nitride semiconductor layer has a depression immediately above the dislocation-concentrated region, and has, in a region thereof other than the depression, a high-quality quantum well active layer with good flatness and without cracks, a layer that, as is grown, readily exhibits p-type conductivity, and a stripe-shaped laser light waveguide region. The laser light waveguide region is formed above the low-dislocation region. This helps realize a nitride semiconductor laser device that offers a longer life.
    Type: Application
    Filed: April 26, 2004
    Publication date: June 30, 2005
    Applicants: Sharp Kabushiki Kaisha, Sumitomo Electric Industries, Ltd.
    Inventors: Yoshihiro Ueta, Teruyoshi Takakura, Takeshi Kamikawa, Yuhzoh Tsuda, Shigetoshi Ito, Takayuki Yuasa, Mototaka Taneya, Kensaku Motoki