Patents by Inventor Kensaku Motoki

Kensaku Motoki 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: 7176499
    Abstract: When a semiconductor light emitting device or a semiconductor device is manufactured by growing nitride III-V compound semiconductor layers, which will form a light emitting device structure or a device structure, on a nitride III-V compound semiconductor substrate composed of a first region in form of a crystal having a first average dislocation density and a plurality of second regions having a second average dislocation density higher than the first average dislocation density and periodically aligned in the first region, device regions are defined on the nitride III-V compound semiconductor substrate such that the device regions do not substantially include second regions, emission regions or active regions of devices finally obtained do not include second regions.
    Type: Grant
    Filed: November 21, 2003
    Date of Patent: February 13, 2007
    Assignees: Sony Corporation, Sumitomo Electric Industries, Ltd.
    Inventors: Tsunenori Asatsuma, Shigetaka Tomiya, Koshi Tamamura, Tsuyoshi Tojo, Osamu Goto, Kensaku Motoki
  • Publication number: 20060286695
    Abstract: A method for producing a semiconductor light emitting device is disclosed. The method comprises the step of growing a nitride type III-V group compound semiconductor layer that forms a light emitting device structure on a principal plane of a nitride type III-V group compound semiconductor substrate on which a plurality of second regions made of a crystal having a second average dislocation density are regularly arranged in a first region made of a crystal having a first average dislocation density so as to produce a semiconductor light emitting device, the second average dislocation density being greater than the first average dislocation density. The nitride type III-V group compound semiconductor layer does not directly contact the second regions on the principal plane of the nitride type III-V group compound semiconductor substrate.
    Type: Application
    Filed: August 28, 2006
    Publication date: December 21, 2006
    Inventors: Katsunori Yanashima, Kensaku Motoki
  • Publication number: 20060273343
    Abstract: Seeds are implanted in a regular pattern upon an undersubstrate. An AlxInyGa1?x?yN (0?x?1, 0?y?1, 0<x+y?1) mixture crystal is grown on the seed implanted undersubstrate by a facet growth method. The facet growth makes facet pits above the seeds. The facets assemble dislocations to the pit bottoms from neighboring regions and make closed defect accumulating regions (H) under the facet bottoms. The closed defect accumulating regions (H) arrest dislocations permanently. Release of dislocations, radial planar defect assemblies and linear defect assemblies are forbidden. The surrounding accompanying low dislocation single crystal regions (Z) and extra low dislocation single crystal regions (Y) are low dislocation density single crystals.
    Type: Application
    Filed: August 10, 2006
    Publication date: December 7, 2006
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Seiji Nakahata, Ryu Hirota, Kensaku Motoki, Takuji Okahisa, Kouji Uematsu
  • Publication number: 20060213429
    Abstract: A low dislocation density GaN single crystal substrate is made by forming a seed mask having parallel stripes regularly and periodically aligning on an undersubstrate, growing a GaN crystal on a facet-growth condition, forming repetitions of parallel facet hills and facet valleys rooted upon the mask stripes, maintaining the facet hills and facet valleys, producing voluminous defect accumulating regions (H) accompanying the valleys, yielding low dislocation single crystal regions (Z) following the facets, making C-plane growth regions (Y) following flat tops between the facets, gathering dislocations on the facets into the valleys by the action of the growing facets, reducing dislocations in the low dislocation single crystal regions (Z) and the C-plane growth regions (Y), and accumulating the dislocations in cores (S) or interfaces (K) of the voluminous defect accumulating regions (H).
    Type: Application
    Filed: May 17, 2006
    Publication date: September 28, 2006
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Kensaku Motoki, Ryu Hirota, Takuji Okahisa, Seiji Nakahata
  • Patent number: 7112826
    Abstract: Seeds are implanted in a regular pattern upon an undersubstrate. A GaN crystal is grown on the seed implanted undersubstrate by a facet growth method. The facet growth makes facet pits above the seeds. The facets assemble dislocations to the pit bottoms from neighboring regions and make closed defect accumulating regions (H) under the facet bottoms. The closed defect accumulating regions (H) arrest dislocations permanently. Release of dislocations, radial planar defect assemblies and linear defect assemblies are forbidden. The surrounding accompanying low dislocation single crystal regions (Z) and extra low dislocation single crystal regions (Y) are low dislocation density single crystals.
    Type: Grant
    Filed: November 5, 2003
    Date of Patent: September 26, 2006
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Kensaku Motoki, Takuji Okahisa, Seiji Nakahata, Ryu Hirota, Koji Uematsu
  • 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
  • Patent number: 7105865
    Abstract: Seeds are implanted in a regular pattern upon an undersubstrate. An AlxInyGa1-x-yN (0?x?1, 0?y?1, 0<x+y?1) mixture crystal is grown on the seed implanted undersubstrate by a facet growth method. The facet growth makes facet pits above the seeds. The facets assemble dislocations to the pit bottoms from neighboring regions and make closed defect accumulating regions (H) under the facet bottoms. The closed defect accumulating regions (H) arrest dislocations permanently. Release of dislocations, radial planar defect assemblies and linear defect assemblies are forbidden. The surrounding accompanying low dislocation single crystal regions (Z) and extra low dislocation single crystal regions (Y) are low dislocation density single crystals.
    Type: Grant
    Filed: January 25, 2005
    Date of Patent: September 12, 2006
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Seiji Nakahata, Ryu Hirota, Kensaku Motoki, Takuji Okahisa, Kouji Uematsu
  • Patent number: 7091056
    Abstract: When a semiconductor light emitting device or a semiconductor device is manufactured by growing nitride III–V compound semiconductor layers, which will form a light emitting device structure or a device structure, on a nitride III–V compound semiconductor substrate composed of a first region in form of a crystal having a first average dislocation density and a plurality of second regions having a second average dislocation density higher than the first average dislocation density and periodically aligned in the first region, device regions are defined on the nitride III–V compound semiconductor substrate such that the device regions do not substantially include second regions, emission regions or active regions of devices finally obtained do not include second regions.
    Type: Grant
    Filed: June 9, 2005
    Date of Patent: August 15, 2006
    Assignees: Sony Corporation, Sumitomo Electric Industries, Ltd.
    Inventors: Tsunenori Asatsuma, Shigetaka Tomiya, Koshi Tamamura, Tsuyoshi Tojo, Osamu Goto, Kensaku Motoki
  • Patent number: 7087114
    Abstract: A low dislocation density GaN single crystal substrate is made by forming a seed mask having parallel stripes regularly and periodically aligning on an undersubstrate, growing a GaN crystal on a facet-growth condition, forming repetitions of parallel facet hills and facet valleys rooted upon the mask stripes, maintaining the facet hills and facet valleys, producing voluminous defect accumulating regions (H) accompanying the valleys, yielding low dislocation single crystal regions (Z) following the facets, making C-plane growth regions (Y) following flat tops between the facets, gathering dislocations on the facets into the valleys by the action of the growing facets, reducing dislocations in the low dislocation single crystal regions (Z) and the C-plane growth regions (Y), and accumulating the dislocations in cores (S) or interfaces (K) of the voluminous defect accumulating regions (H).
    Type: Grant
    Filed: October 8, 2002
    Date of Patent: August 8, 2006
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Kensaku Motoki, Ryu Hirota, Takuji Okahisa, Seiji Nakahata
  • Publication number: 20060172513
    Abstract: A method for producing a semiconductor light emitting device is disclosed. The method comprises the step of growing a nitride type III-V group compound semiconductor layer that forms a light emitting device structure on a principal plane of a nitride type III-V group compound semiconductor substrate on which a plurality of second regions made of a crystal having a second average dislocation density are regularly arranged in a first region made of a crystal having a first average dislocation density so as to produce a semiconductor light emitting device, the second average dislocation density being greater than the first average dislocation density. The nitride type III-V group compound semiconductor layer does not directly contact the second regions on the principal plane of the nitride type III-V group compound semiconductor substrate.
    Type: Application
    Filed: April 13, 2006
    Publication date: August 3, 2006
    Inventors: Katsunori Yanashima, Kensaku Motoki
  • Publication number: 20060097353
    Abstract: Oxygen can be doped into a gallium nitride crystal by preparing a non-C-plane gallium nitride seed crystal, supplying material gases including gallium, nitrogen and oxygen to the non-C-plane gallium nitride seed crystal, growing a non-C-plane gallium nitride crystal on the non-C-plane gallium nitride seed crystal and allowing oxygen to infiltrating via a non-C-plane surface to the growing gallium nitride crystal.
    Type: Application
    Filed: December 22, 2005
    Publication date: May 11, 2006
    Inventors: Kensaku Motoki, Masaki Ueno
  • Patent number: 7015058
    Abstract: A nitride semiconductor laser device using a group III nitride semiconductor also as a substrate offers excellent operation characteristics and a long laser oscillation life. In a layered structure of a group III nitride semiconductor formed on a GaN substrate, a laser optical waveguide region is formed elsewhere than right above a dislocation-concentrated region extending so as to vertically penetrate the substrate, and electrodes are formed on the top surface of the layered structure and on the bottom surface of the substrate elsewhere than right above or below the dislocation-concentrated region. In a portion of the top surface of the layered structure and in a portion of the bottom surface of the substrate right above and below the dislocation-concentrated region, dielectric layers may be formed to prevent the electrodes from making contact with those regions.
    Type: Grant
    Filed: August 13, 2004
    Date of Patent: March 21, 2006
    Assignees: Sharp Kabushiki Kaisha, Sumitomo Electric Industries, Ltd.
    Inventors: Kunihiro Takatani, Shigetoshi Ito, Takayuki Yuasa, Mototaka Taneya, Kensaku Motoki
  • Patent number: 7012318
    Abstract: Oxygen can be doped into a gallium nitride crystal by preparing a non-C-plane gallium nitride seed crystal, supplying material gases including gallium, nitrogen and oxygen to the non-C-plane gallium nitride seed crystal, growing a non-C-plane gallium nitride crystal on the non-C-plane gallium nitride seed crystal and allowing oxygen to infiltrate via a non-C-plane surface to the growing gallium nitride crystal. Otherwise, oxygen can be doped into a gallium nitride crystal by preparing a C-plane gallium nitride seed crystal or a three-rotationally symmetric plane foreign material seed crystal, supplying material gases including gallium, nitrogen and oxygen to the C-plane gallium nitride seed crystal or the three-rotationally symmetric foreign seed crystal, growing a faceted C-plane gallium nitride crystal having facets of non-C-planes on the seed crystal, maintaining the facets on the C-plane gallium nitride crystal and allowing oxygen to infiltrate via the non-C-plane facets to the gallium nitride crystal.
    Type: Grant
    Filed: May 17, 2004
    Date of Patent: March 14, 2006
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Kensaku Motoki, Masaki Ueno
  • Publication number: 20050227458
    Abstract: When a semiconductor light emitting device or a semiconductor device is produced using a nitride type III-V group compound semiconductor substrate on which a plurality of second regions made of a crystal having a second average dislocation density are regularly arranged in a first region made of a crystal having a first average dislocation density so as to produce the structured substrate, the second average dislocation density being greater than the first average dislocation density, a light emitting region of the semiconductor light emitting device or an active region of the semiconductor device is formed in such a manner that it does not pass through any one of the second regions.
    Type: Application
    Filed: March 30, 2004
    Publication date: October 13, 2005
    Inventors: Toshimasa Kobayashi, Kensaku Motoki
  • Publication number: 20050227392
    Abstract: When a semiconductor light emitting device or a semiconductor device is manufactured by growing nitride III-V compound semiconductor layers, which will form a light emitting device structure or a device structure, on a nitride III-V compound semiconductor substrate composed of a first region in form of a crystal having a first average dislocation density and a plurality of second regions having a second average dislocation density higher than the first average dislocation density and periodically aligned in the first region, device regions are defined on the nitride III-V compound semiconductor substrate such that the device regions do not substantially include second regions, emission regions or active regions of devices finally obtained do not include second regions.
    Type: Application
    Filed: June 9, 2005
    Publication date: October 13, 2005
    Inventors: Tsunenori Asatsuma, Shigetaka Tomiya, Koshi Tamamura, Tsuyoshi Tojo, Osamu Goto, Kensaku Motoki
  • Publication number: 20050221515
    Abstract: A method for producing a semiconductor light emitting device is disclosed. The method comprises the step of growing a nitride type III-V group compound semiconductor layer that forms a light emitting device structure on a principal plane of a nitride type III-V group compound semiconductor substrate on which a plurality of second regions made of a crystal having a second average dislocation density are regularly arranged in a first region made of a crystal having a first average dislocation density so as to produce a semiconductor light emitting device, the second average dislocation density being greater than the first average dislocation density. The nitride type III-V group compound semiconductor layer does not directly contact the second regions on the principal plane of the nitride type III-V group compound semiconductor substrate.
    Type: Application
    Filed: March 30, 2004
    Publication date: October 6, 2005
    Inventors: Katsunori Yanashima, Kensaku Motoki
  • Publication number: 20050208687
    Abstract: Manufacture at lower cost of off-axis GaN single-crystal freestanding substrates having a crystal orientation that is displaced from (0001) instead of (0001) exact. With an off-axis (111) GaAs wafer as a starting substrate, GaN is vapor-deposited onto the starting substrate, which grows GaN crystal that is inclined at the same off-axis angle and in the same direction as is the starting substrate. Misoriented freestanding GaN substrates may be manufactured, utilizing a misoriented (111) GaAs baseplate as a starting substrate, by forming onto the starting substrate a mask having a plurality of apertures, depositing through the mask a GaN single-crystal layer, and then removing the starting substrate. The manufacture of GaN crystal having a misorientation of 0.1° to 25° is made possible.
    Type: Application
    Filed: March 17, 2005
    Publication date: September 22, 2005
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Hitoshi Kasai, Kensaku Motoki
  • Publication number: 20050183658
    Abstract: A low dislocation density AlxInyGa1-x-yN single crystal substrate is made by forming a seed mask having parallel stripes regularly and periodically aligning on an undersubstrate, growing an AlxInyGa1-x-yN crystal on a facet-growth condition, forming repetitions of parallel facet hills and facet valleys rooted upon the mask stripes, maintaining the facet hills and facet valleys, producing voluminous defect accumulating regions (H) accompanying the valleys, yielding low dislocation single crystal regions (Z) following the facets, making C-plane growth regions (Y) following flat tops between the facets, gathering dislocations on the facets into the valleys by the action of the growing facets, reducing dislocations in the low dislocation single crystal regions (Z) and the C-plane growth regions (Y), and accumulating the dislocations in cores (S) or interfaces (K) of the voluminous defect accumulating regions (H).
    Type: Application
    Filed: March 1, 2005
    Publication date: August 25, 2005
    Inventors: Seiji Nakahata, Ryu Hirota, Kensaku Motoki, Takuji Okahisa, Koji Uematsu
  • Publication number: 20050161697
    Abstract: Seeds are implanted in a regular pattern upon an undersubstrate. An AlxInyGa1-x-yN (0?×?1, 0?y?1, 0<x+y?1) mixture crystal is grown on the seed implanted undersubstrate by a facet growth method. The facet growth makes facet pits above the seeds. The facets assemble dislocations to the pit bottoms from neighboring regions and make closed defect accumulating regions (H) under the facet bottoms. The closed defect accumulating regions (H) arrest dislocations permanently. Release of dislocations, radial planar defect assemblies and linear defect assemblies are forbidden. The surrounding accompanying low dislocation single crystal regions (Z) and extra low dislocation single crystal regions (Y) are low dislocation density single crystals.
    Type: Application
    Filed: January 25, 2005
    Publication date: July 28, 2005
    Inventors: Seiji Nakahata, Ryu Hirota, Kensaku Motoki, Takuji Okahisa, Kouji Uematsu
  • 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