Patents by Inventor Toshiyuki Oka

Toshiyuki Oka 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: 9368682
    Abstract: According to one embodiment, a semiconductor light emitting device includes a stacked structure body, a first electrode, a second electrode, and a dielectric body part. The stacked structure body includes a first semiconductor layer, having a first portion and a second portion juxtaposed with the first portion, a light emitting layer provided on the second portion, a second semiconductor layer provided on the light emitting layer. The first electrode includes a contact part provided on the first portion and contacting the first layer. The second electrode includes a first part provided on the second semiconductor layer and contacting the second layer, and a second part electrically connected with the first part and including a portion overlapping with the contact part when viewed from the first layer toward the second layer. The dielectric body part is provided between the contact part and the second part.
    Type: Grant
    Filed: May 15, 2015
    Date of Patent: June 14, 2016
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroshi Katsuno, Satoshi Mitsugi, Toshiyuki Oka, Shinya Nunoue
  • Patent number: 9312436
    Abstract: According to one embodiment, a nitride semiconductor device includes a first layer and a functional layer. The first layer is formed on an amorphous layer, includes aluminum nitride, and has a compressive strain or a tensile strain. The functional layer is formed on the first layer and includes a nitride semiconductor.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: April 12, 2016
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroshi Ono, Tomonari Shioda, Naoharu Sugiyama, Toshiyuki Oka, Shinya Nunoue
  • Patent number: 9299889
    Abstract: According to one embodiment, a semiconductor light emitting device includes a stacked structure body, a first electrode, a second electrode, and a dielectric body part. The stacked structure body includes a first semiconductor layer, having a first portion and a second portion juxtaposed with the first portion, a light emitting layer provided on the second portion, a second semiconductor layer provided on the light emitting layer. The first electrode includes a contact part provided on the first portion and contacting the first layer. The second electrode includes a first part provided on the second semiconductor layer and contacting the second layer, and a second part electrically connected with the first part and including a portion overlapping with the contact part when viewed from the first layer toward the second layer. The dielectric body part is provided between the contact part and the second part.
    Type: Grant
    Filed: March 10, 2014
    Date of Patent: March 29, 2016
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroshi Katsuno, Satoshi Mitsugi, Toshiyuki Oka, Shinya Nunoue
  • Patent number: 9209362
    Abstract: A semiconductor light emitting device has a light emitting element, a first electrode layer, a second electrode layer, a seed electrode layer and a plated layer. The light emitting element has a nitride-based III-V compound semiconductor on a substrate. The light emitting element having a light extraction surface. The first electrode layer on the light extraction surface. The second electrode layer is provided on a surface opposite to the light extraction surface of the light emitting element. The seed electrode layer is configured to cover the entire surface of the second electrode layer. The plated layer is provided on the seed electrode layer. The light emitting element has a light emitting layer, a first conductive type semiconductor layer, and a second conductive type semiconductor layer.
    Type: Grant
    Filed: May 22, 2014
    Date of Patent: December 8, 2015
    Assignee: KABUSHIKI KAISHA TOSHIBA
    Inventors: Toru Gotoda, Toshiyuki Oka, Shinya Nunoue, Kotaro Zaima
  • Patent number: 9202986
    Abstract: According to one embodiment, a semiconductor light emitting device includes first and second conductive layers, a first semiconductor layer of a first conductivity type, a second semiconductor layer of a second conductivity type, and a light emitting part. The second semiconductor layer is provided between the first conductive layer and the first semiconductor layer. The light emitting part is provided between the first and second semiconductor layers. The second conductive layer is in contact with the second semiconductor layer and the first conductive layer between the second semiconductor layer and the first conductive layer. The first and second conductive layers are transmittable to light emitted from the light emitting part. The first conductive layer includes a polycrystal having a first average grain diameter. The second conductive layer includes a polycrystal having a second average grain diameter of 150 nanometers or less and smaller than the first average grain diameter.
    Type: Grant
    Filed: November 25, 2013
    Date of Patent: December 1, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Toshihide Ito, Toshiyuki Oka, Shinya Nunoue
  • Patent number: 9159878
    Abstract: According to one embodiment, a semiconductor light emitting device includes a stacked structural body, a first electrode, and a second electrode. The stacked structural body includes a first semiconductor layer of a first conductivity type, a second semiconductor layer of a second conductivity type, and a light emitting portion. The stacked structural body has a first major surface on a side of the second semiconductor layer. The first electrode is provided on the first semiconductor. The second electrode is provided on the second semiconductor layer. The first electrode includes a first pad portion and a first extending portion that extends from the first pad portion along a first extending direction. The first extending portion includes a first width-increasing portion. A width of the first width-increasing portion along a direction orthogonal to the first extending direction is increased from the first pad portion toward an end of the first extending portion.
    Type: Grant
    Filed: May 13, 2013
    Date of Patent: October 13, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shigeya Kimura, Taisuke Sato, Toshihide Ito, Toshiyuki Oka, Shinya Nunoue
  • Publication number: 20150280061
    Abstract: According to one embodiment, a semiconductor light emitting device includes first and second conductive layers, a first semiconductor layer of a first conductivity type, a second semiconductor layer of a second conductivity type, and a light emitting part. The second semiconductor layer is provided between the first conductive layer and the first semiconductor layer. The light emitting part is provided between the first and second semiconductor layers. The second conductive layer is in contact with the second semiconductor layer and the first conductive layer between the second semiconductor layer and the first conductive layer. The first and second conductive layers are transmittable to light emitted from the light emitting part. The first conductive layer includes a polycrystal having a first average grain diameter. The second conductive layer includes a polycrystal having a second average grain diameter of 150 nanometers or less and smaller than the first average grain diameter.
    Type: Application
    Filed: June 16, 2015
    Publication date: October 1, 2015
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Toshihide ITO, Toshiyuki OKA, Shinya NUNOUE
  • Publication number: 20150263230
    Abstract: According to one embodiment, a semiconductor light emitting device includes a stacked structure body, a first electrode, a second electrode, and a dielectric body part. The stacked structure body includes a first semiconductor layer, having a first portion and a second portion juxtaposed with the first portion, a light emitting layer provided on the second portion, a second semiconductor layer provided on the light emitting layer. The first electrode includes a contact part provided on the first portion and contacting the first layer. The second electrode includes a first part provided on the second semiconductor layer and contacting the second layer, and a second part electrically connected with the first part and including a portion overlapping with the contact part when viewed from the first layer toward the second layer. The dielectric body part is provided between the contact part and the second part.
    Type: Application
    Filed: May 15, 2015
    Publication date: September 17, 2015
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Hiroshi KATSUNO, Satoshi Mitsugi, Toshiyuki Oka, Shinya Nunoue
  • Patent number: 9082931
    Abstract: According to one embodiment, a semiconductor light emitting device includes a stacked structure body, a first electrode, a second electrode, and a dielectric body part. The stacked structure body includes a first semiconductor layer, having a first portion and a second portion juxtaposed with the first portion, a light emitting layer provided on the second portion, a second semiconductor layer provided on the light emitting layer. The first electrode includes a contact part provided on the first portion and contacting the first layer. The second electrode includes a first part provided on the second semiconductor layer and contacting the second layer, and a second part electrically connected with the first part and including a portion overlapping with the contact part when viewed from the first layer toward the second layer. The dielectric body part is provided between the contact part and the second part.
    Type: Grant
    Filed: August 31, 2011
    Date of Patent: July 14, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroshi Katsuno, Satoshi Mitsugi, Toshiyuki Oka, Shinya Nunoue
  • Patent number: 9018665
    Abstract: Certain embodiments provide a method for manufacturing a semiconductor light emitting device, including: providing a first stack film on a first substrate, the first stack film being formed by stacking a p-type nitride semiconductor layer, an active layer having a multiquantum well structure of a nitride semiconductor, and an n-type nitride semiconductor layer in this order; forming an n-electrode on an upper face of the n-type nitride semiconductor layer; and forming a concave-convex region on the upper face of the n-type nitride semiconductor layer by performing wet etching on the upper face of the n-type nitride semiconductor layer with the use of an alkaline solution, except for a region in which the n-electrode is formed.
    Type: Grant
    Filed: July 9, 2014
    Date of Patent: April 28, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kotaro Zaima, Toru Gotoda, Toshiyuki Oka, Shinya Nunoue
  • Patent number: 9006013
    Abstract: According to one embodiment, a method is disclosed for manufacturing a semiconductor light emitting device. The method can include forming a nitride semiconductor layer including a light emitting layer on a first substrate having an unevenness, bonding the nitride layer to a second substrate, and separating the first substrate from the nitride layer by irradiating the nitride layer with light. The forming the nitride layer includes leaving a cavity in a space inside a depression of the unevenness while forming a thin film on the depression. The film includes a same material as part of the nitride layer. The separating includes causing the film to absorb part of the light so that intensity of the light applied to a portion of the nitride layer facing the depression is made lower than intensity of the light applied to a portion facing a protrusion of the unevenness.
    Type: Grant
    Filed: February 27, 2012
    Date of Patent: April 14, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Toru Gotoda, Toshiyuki Oka, Shinya Nunoue, Kotaro Zaima, Hiroshi Ono, Hajime Nago
  • Patent number: 8994054
    Abstract: According to one embodiment, a semiconductor light emitting device includes a stacked structural body, a first electrode, a second electrode, a third electrode, and a fourth electrode. The stacked structural body includes a first semiconductor layer, a second semiconductor layer, and a light emitting layer provided between the first semiconductor layer and the second semiconductor layer. The first electrode is electrically connected to the first semiconductor layer. The second electrode forms an ohmic contact with the second semiconductor layer. The second electrode is translucent to light emitted from the light emitting layer. The third electrode penetrates through the second electrode and is electrically connected to the second electrode to form Shottky contact with the second semiconductor layer. The third electrode is disposed between the fourth electrode and the second semiconductor layer.
    Type: Grant
    Filed: August 2, 2011
    Date of Patent: March 31, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Eiji Muramoto, Shinya Nunoue, Toshiyuki Oka
  • Patent number: 8981398
    Abstract: Certain embodiments provide a semiconductor light emitting device including: a first metal layer; a stack film including a p-type nitride semiconductor layer, an active layer, and an n-type nitride semiconductor layer; an n-electrode; a second metal layer; and a protection film protecting an outer circumferential region of the upper face of the n-type nitride semiconductor layer, side faces of the stack film, a region of an upper face of the second metal layer other than a region in contact with the p-type nitride semiconductor layer, and a region of an upper face of the first metal layer other than a region in contact with the second metal layer. Concavities and convexities are formed in a region of the upper face of the n-type nitride semiconductor layer, the region being outside the region in which the n-electrode is provided and being outside the regions covered with the protection film.
    Type: Grant
    Filed: April 15, 2014
    Date of Patent: March 17, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kotaro Zaima, Toru Gotoda, Toshiyuki Oka, Shinya Nunoue
  • Patent number: 8963176
    Abstract: According to one embodiment, a semiconductor light-emitting device includes an n-type semiconductor layer including a nitride semiconductor, a p-type semiconductor layer including a nitride semiconductor, a light-emitting portion and a stacked body. The light-emitting portion is provided between the n-type and p-type semiconductor layers and includes a barrier layer and a well layer. The well layer is stacked with the barrier layer. The stacked body is provided between the light-emitting portion and the n-type semiconductor layer and includes a first layer and a second layer. The second layer is stacked with the first layer. Average In composition ratio of the stacked body is higher than 0.4 times average In composition ratio of the light-emitting portion. The layer thickness tb of the barrier layer is 10 nanometers or less.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: February 24, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shigeya Kimura, Hajime Nago, Toshiyuki Oka, Koichi Tachibana, Toshiki Hikosaka, Shinya Nunoue
  • Patent number: 8890195
    Abstract: According to one embodiment, a semiconductor light emitting device includes a stacked structural body, a first, a second and a third conductive layer. The stacked structural body includes first and second semiconductors and a light emitting layer provided therebetween. The second semiconductor layer is disposed between the first conductive layer and the light emitting layer. The first conductive layer is transparent. The first conductive layer has a first major surface on a side opposite to the second semiconductor layer. The second conductive layer is in contact with the first major surface. The third conductive layer is in contact with the first major surface and has a reflectance higher than a reflectance of the second conductive layer. The third conductive layer includes an extending part extending in parallel to the first major surface. At least a portion of the extending part is not covered by the second conductive layer.
    Type: Grant
    Filed: January 23, 2013
    Date of Patent: November 18, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Taisuke Sato, Toshiyuki Oka, Koichi Tachibana, Shinya Nunoue
  • Patent number: 8877526
    Abstract: According to one embodiment, a semiconductor light emitting device includes a first semiconductor layer, a second semiconductor layer and a light emitting part. The first semiconductor layer includes an n-type semiconductor layer. The second semiconductor layer includes a p-type semiconductor layer. The light emitting part is provided between the first semiconductor layer and the second semiconductor layer, and includes a plurality of barrier layers and a well layer provided between the plurality of barrier layers. The first semiconductor layer has a first irregularity and a second irregularity. The first irregularity is provided on a first major surface of the first semiconductor layer on an opposite side to the light emitting part. The second irregularity is provided on a bottom face and a top face of the first irregularity, and has a level difference smaller than a level difference between the bottom face and the top face.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: November 4, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroshi Ono, Toshiki Hikosaka, Tomoko Morioka, Toshiyuki Oka, Shinya Nunoue
  • Publication number: 20140319458
    Abstract: Certain embodiments provide a method for manufacturing a semiconductor light emitting device, including: providing a first stack film on a first substrate, the first stack film being formed by stacking a p-type nitride semiconductor layer, an active layer having a multiquantum well structure of a nitride semiconductor, and an n-type nitride semiconductor layer in this order; forming an n-electrode on an upper face of the n-type nitride semiconductor layer; and forming a concave-convex region on the upper face of the n-type nitride semiconductor layer by performing wet etching on the upper face of the n-type nitride semiconductor layer with the use of an alkaline solution, except for a region in which the n-electrode is formed.
    Type: Application
    Filed: July 9, 2014
    Publication date: October 30, 2014
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Kotaro ZAIMA, Toru Gotoda, Toshiyuki Oka, Shinya Nunoue
  • Patent number: 8859307
    Abstract: According to an embodiment, a method for manufacturing a semiconductor device includes a placement step and a bonding step. The placement step faces a semiconductor active portion toward a support substrate portion via a bonding portion disposed between the semiconductor active portion and the support substrate portion. The bonding portion includes a bonding layer and a light absorption layer, absorptance of the light absorption layer for laser light being higher than or equal to absorptance of the bonding layer for the laser light. The bonding step bonds the semiconductor active portion and the support substrate portion by irradiating the light absorption layer with the laser light through the support substrate portion and melting the bonding layer by thermal conduction from the light absorption layer heated by the laser light.
    Type: Grant
    Filed: August 31, 2012
    Date of Patent: October 14, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Satoshi Mitsugi, Toshiyuki Oka, Shinya Nunoue, Hiroshi Katsuno
  • Publication number: 20140284647
    Abstract: A semiconductor light emitting device has a light emitting element, a first electrode layer, a second electrode layer, a seed electrode layer and a plated layer. The light emitting element has a nitride-based III-V compound semiconductor on a substrate. The light emitting element having a light extraction surface. The first electrode layer on the light extraction surface. The second electrode layer is provided on a surface opposite to the light extraction surface of the light emitting element. The seed electrode layer is configured to cover the entire surface of the second electrode layer. The plated layer is provided on the seed electrode layer. The light emitting element has a light emitting layer, a first conductive type semiconductor layer, and a second conductive type semiconductor layer.
    Type: Application
    Filed: May 22, 2014
    Publication date: September 25, 2014
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Toru GOTODA, Toshiyuki OKA, Shinya NUNOUE, Kotaro ZAlMA
  • Patent number: 8822250
    Abstract: Certain embodiments provide a method for manufacturing a semiconductor light emitting device, including: providing a first stack film on a first substrate, the first stack film being formed by stacking a p-type nitride semiconductor layer, an active layer having a multiquantum well structure of a nitride semiconductor, and an n-type nitride semiconductor layer in this order; forming an n-electrode on an upper face of the n-type nitride semiconductor layer; and forming a concave-convex region on the upper face of the n-type nitride semiconductor layer by performing wet etching on the upper face of the n-type nitride semiconductor layer with the use of an alkaline solution, except for a region in which the n-electrode is formed.
    Type: Grant
    Filed: October 31, 2012
    Date of Patent: September 2, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kotaro Zaima, Toru Gotoda, Toshiyuki Oka, Shinya Nunoue