Patents by Inventor Kei Kaneko

Kei Kaneko 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).

  • Publication number: 20140361345
    Abstract: A nitride semiconductor wafer includes a silicon substrate, a first layer, a second layer, a third layer, a fourth layer, a fifth layer, and a sixth layer. The first layer is provided on the silicon substrate. The second layer is provided on the first layer. The third layer is provided on the second layer. The fourth layer is provided on the third layer. The fifth layer is provided on the fourth layer. The sixth layer is provided on the fifth layer. A composition ratio x4 of the fourth layer decreases in a first direction from the third layer toward the fifth layer. A maximum value of the composition ratio x4 is not more than a composition ratio of the third layer. A minimum value of the composition ratio x4 is not less than a composition ratio of the fifth layer.
    Type: Application
    Filed: February 7, 2014
    Publication date: December 11, 2014
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Kei KANEKO, Mitsuhiro Kushibe, Hiroshi Katsuno, Shinji Yamada, Jumpei Tajima, Yasuo Ohba
  • Patent number: 8890193
    Abstract: A method for manufacturing a semiconductor light emitting apparatus having first semiconductor layer and second semiconductor layer sandwiching a light emitting layer, first and second electrodes provided on respective major surfaces of the first semiconductor and second semiconductor layers to connect thereto, stacked dielectric films having different refractive indexes provided on portions of the major surfaces not covered by the first and second electrodes, and a protruding portion erected on at least a portion of a rim of at least one of the first and second electrodes. The mounting member includes a connection member connected to at least one of the first and second electrodes. The method includes causing the semiconductor light emitting device and a mounting member to face each other, and causing the connection member to contact and join to the at least one of the first and second electrodes using the protruding portion as a guide.
    Type: Grant
    Filed: November 16, 2012
    Date of Patent: November 18, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroshi Katsuno, Yasuo Ohba, Kei Kaneko, Mitsuhiro Kushibe
  • Publication number: 20140327027
    Abstract: A semiconductor light emitting element, includes: a laminated structure body including an n-type semiconductor layer, a p-type semiconductor layer, and a light emitting layer; a p-side electrode provided in contact with the p-type semiconductor layer; an n-side electrode provided in contact with the n-type semiconductor layer; a highly reflective insulating layer provided in contact with the n-type semiconductor layer and having a higher reflectance than a reflectance of the n-side electrode; and an upper metal layer provided on at least a part of the n-side electrode and on at least a part of the highly reflective insulating layer and electrically connected to the n-side electrode. An area of a region of the n-side electrode in contact with the n-type semiconductor layer is smaller than an area of a region of the highly reflective insulating layer sandwiched between the n-type semiconductor layer and the upper metal layer.
    Type: Application
    Filed: July 16, 2014
    Publication date: November 6, 2014
    Inventors: Hiroshi Katsuno, Yasuo Ohba, Kei Kaneko, Mitsuhiro Kushibe
  • Publication number: 20140217360
    Abstract: A semiconductor light-emitting element includes, a first semiconductor layer, a second semiconductor layer, a light-emitting layer provided between the first semiconductor layer and the second semiconductor layer, a first electrode connected to the first semiconductor layer, and a second electrode provided on the second semiconductor layer. A side of the second electrode facing to the second semiconductor layer is composed of at least any one of silver and silver alloy. The second electrode has a void having a width of emission wavelength or less of the light-emitting layer in a plane of the second electrode facing to the second semiconductor layer.
    Type: Application
    Filed: April 4, 2014
    Publication date: August 7, 2014
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Hiroshi Katsuno, Yasuo Ohba, Kei Kaneko
  • Patent number: 8791498
    Abstract: A semiconductor light emitting device, includes: a stacked structural unit including a first semiconductor layer of a first conductivity type, a second semiconductor layer of a second conductivity type, and a light emitting layer provided therebetween; and an electrode including a first and second metal layers, the first metal layer including silver or silver alloy and being provided on a side of the second semiconductor layer opposite to the light emitting layer, the second metal layer including at least one element selected from gold, platinum, palladium, rhodium, iridium, ruthenium, and osmium and being provided on a side of the first metal layer opposite to the second semiconductor layer. A concentration of the element in a region including an interface between the first and second semiconductor layers is higher than that of the element in a region of the first metal layer distal to the interface.
    Type: Grant
    Filed: March 8, 2010
    Date of Patent: July 29, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroshi Katsuno, Yasuo Ohba, Kei Kaneko, Mitsuhiro Kushibe
  • Patent number: 8729594
    Abstract: A semiconductor light-emitting element includes, a first semiconductor layer, a second semiconductor layer, a light-emitting layer provided between the first semiconductor layer and the second semiconductor layer, a first electrode connected to the first semiconductor layer, and a second electrode provided on the second semiconductor layer. A side of the second electrode facing to the second semiconductor layer is composed of at least any one of silver and silver alloy. The second electrode has a void having a width of emission wavelength or less of the light-emitting layer in a plane of the second electrode facing to the second semiconductor layer.
    Type: Grant
    Filed: January 18, 2013
    Date of Patent: May 20, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroshi Katsuno, Yasuo Ohba, Kei Kaneko
  • Patent number: 8729583
    Abstract: According to one embodiment, a semiconductor light-emitting device includes a first semiconductor layer, a second semiconductor layer, a light-emitting layer, a third semiconductor layer and a first electrode. The first semiconductor layer of a first conductivity type has a first major surface provided with a first surface asperity. The second semiconductor layer of a second conductivity type is provided on an opposite side of the first semiconductor layer from the first major surface. The light-emitting layer is provided between the first and second semiconductor layers. The first semiconductor layer is disposed between a third semiconductor layer and the light-emitting layer. The third semiconductor layer has an impurity concentration lower than an impurity concentration of the first semiconductor layer, and includes an opening exposing the first surface asperity.
    Type: Grant
    Filed: September 1, 2010
    Date of Patent: May 20, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroshi Katsuno, Yasuo Ohba, Mitsuhiro Kushibe, Kei Kaneko, Shinji Yamada
  • Patent number: 8692228
    Abstract: A semiconductor light emitting device includes a first layer including at least one of n-type GaN and n-type AlGaN; a second layer including Mg-containing p-type AlGaN; and a light emitting section provided between the first and second layers. The light emitting section includes barrier layers of Si-containing AlxGa1-x-yInyN (0?x, 0?y, x+y?1), and a well layer provided between the barrier layers and made of GaInN or AlGaInN. The barrier layers have a nearest barrier layer nearest to the second layer among the barrier layers and a far barrier layer. The nearest barrier layer includes a first portion made of Si-containing AlxGa1-x-yInyN (0?x, 0?y, x+y?1), and a second portion provided between the first portion and the second layer and made of AlxGa1-x-yInyN (0?x, 0?y, x+y?1). The Si concentration in the second portion is lower than those in the first portion and in the far barrier layer.
    Type: Grant
    Filed: November 8, 2012
    Date of Patent: April 8, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kei Kaneko, Yasuo Ohba, Hiroshi Katsuno, Mitsuhiro Kushibe
  • Publication number: 20140091350
    Abstract: A semiconductor light emitting device, includes: a stacked structural unit including a first semiconductor layer of a first conductivity type, a second semiconductor layer of a second conductivity type, and a light emitting layer provided therebetween; and an electrode including a first and second metal layers, the first metal layer including silver or silver alloy and being provided on a side of the second semiconductor layer opposite to the light emitting layer, the second metal layer including at least one element selected from gold, platinum, palladium, rhodium, iridium, ruthenium, and osmium and being provided on a side of the first metal layer opposite to the second semiconductor layer. A concentration of the element in a region including an interface between the first and second semiconductor layers is higher than that of the element in a region of the first metal layer distal to the interface.
    Type: Application
    Filed: December 13, 2013
    Publication date: April 3, 2014
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Hiroshi Katsuno, Yasuo Ohba, Kei Kaneko, Mitsuhiro Kushibe
  • Publication number: 20140021441
    Abstract: A semiconductor light emitting device includes: a stacked structure unit including first and second semiconductor layers and a light emitting layer between the first and second semiconductor layers; a first electrode on a first major surface of the stacked structure unit on the second semiconductor layer side to connect to the first semiconductor layer; and a second electrode on the first major surface of the stacked structure unit to connect to the second semiconductor layer. The second electrode includes: a first film on the second semiconductor layer and a second film on a rim of the first film. The first film has a relatively lower contact resistance with the second semiconductor layer, compared to the second film. A distance from an outer edge of the second film to the first film is smaller at a central portion than at a peripheral portion of the first major surface.
    Type: Application
    Filed: July 16, 2013
    Publication date: January 23, 2014
    Inventors: Hiroshi Katsuno, Yasuo Ohba, Kei Kaneko, Mitsuhiro Kushibe
  • Publication number: 20130299847
    Abstract: A semiconductor light emitting device includes: a laminated structure body including an n-type semiconductor layer, a p-type semiconductor layer and a light emitting layer provided between the n-type semiconductor layer and the p-type semiconductor layer; a first electrode connected to the n-type semiconductor layer and containing at least one of silver and a silver alloy; and a second electrode connected to the p-type semiconductor layer.
    Type: Application
    Filed: July 12, 2013
    Publication date: November 14, 2013
    Inventors: Hiroshi KATSUNO, Yasuo Ohba, Kei Kaneko, Mitsuhiro Kushibe
  • Patent number: 8569738
    Abstract: According to one embodiment, a semiconductor light emitting device includes a first layer, a second layer, and a light emitting portion. The first layer includes at least one of n-type GaN and n-type AlGaN. The second layer includes p-type AlGaN. The light emitting portion has a single quantum well structure. The single quantum well structure includes a first barrier layer, a second barrier layer, and a well layer. The first barrier layer is provided between the first layer and the second layer and includes Alx1Ga1-x1-y1Iny1N (0<x1, 0?y1, x1+y1<1). The second barrier layer is provided between the first barrier layer and the second layer and includes Alx2Ga1-x2-y2Iny2N (0<x2, 0?y2, x2+y2<1). The well layer is provided between the first barrier layer and the second barrier layer, includes Alx0Ga1-x0-y0Iny0N (0?x0, 0<y0, x0+y0<1, y1<y0, y2<y0), and is configured to emit near ultraviolet light.
    Type: Grant
    Filed: September 7, 2010
    Date of Patent: October 29, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Mitsuhiro Kushibe, Yasuo Ohba, Kei Kaneko, Hiroshi Katsuno, Shinji Yamada
  • Publication number: 20130256691
    Abstract: A method for manufacturing a semiconductor light emitting device is provided. The device includes: an n-type semiconductor layer; a p-type semiconductor layer; and a light emitting unit provided between the n-type semiconductor layer and the p-type semiconductor layer. The method includes: forming a buffer layer made of a crystalline AlxGa1?xN (0.8?x?1) on a first substrate made of c-plane sapphire and forming a GaN layer on the buffer layer; stacking the n-type semiconductor layer, the light emitting unit, and the p-type semiconductor layer on the GaN layer; and separating the first substrate by irradiating the GaN layer with a laser having a wavelength shorter than a bandgap wavelength of GaN from the first substrate side through the first substrate and the buffer layer.
    Type: Application
    Filed: May 24, 2013
    Publication date: October 3, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Yasuo Ohba, Kei Kaneko, Toru Gotoda, Hiroshi Katsuno, Mitsuhiro Kushibe
  • Patent number: 8513687
    Abstract: A semiconductor light emitting device, includes: a stacked structure unit including a first semiconductor layer, a second semiconductor layer, and a light emitting layer provided between the first semiconductor layer and the second semiconductor layer; a first electrode provided on a first major surface of the stacked structure unit on the second semiconductor layer side to connect to the first semiconductor layer; and a second electrode provided on the first major surface of the stacked structure unit to connect to the second semiconductor layer. The second electrode includes: a first film provided on the second semiconductor layer; and a second film provided on a rim of the first film on the second semiconductor layer. The first film has a relatively low contact resistance with the second semiconductor layer. The second film has a relatively high contact resistance with the second semiconductor layer.
    Type: Grant
    Filed: August 27, 2009
    Date of Patent: August 20, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroshi Katsuno, Yasuo Ohba, Kei Kaneko, Mitsuhiro Kushibe
  • Patent number: 8470627
    Abstract: A method for manufacturing a semiconductor light emitting device is provided. The device includes: an n-type semiconductor layer; a p-type semiconductor layer; and a light emitting unit provided between the n-type semiconductor layer and the p-type semiconductor layer. The method includes: forming a buffer layer made of a crystalline AlxGa1-xN (0.8?x?1) on a first substrate made of c-plane sapphire and forming a GaN layer on the buffer layer; stacking the n-type semiconductor layer, the light emitting unit, and the p-type semiconductor layer on the GaN layer; and separating the first substrate by irradiating the GaN layer with a laser having a wavelength shorter than a bandgap wavelength of GaN from the first substrate side through the first substrate and the buffer layer.
    Type: Grant
    Filed: November 8, 2012
    Date of Patent: June 25, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yasuo Ohba, Kei Kaneko, Toru Gotoda, Hiroshi Katsuno, Mitsuhiro Kushibe
  • Publication number: 20130146914
    Abstract: A method for manufacturing a semiconductor light emitting apparatus having first semiconductor layer and second semiconductor layer sandwiching a light emitting layer, first and second electrodes provided on respective major surfaces of the first semiconductor and second semiconductor layers to connect thereto, stacked dielectric films having different refractive indexes provided on portions of the major surfaces not covered by the first and second electrodes, and a protruding portion erected on at least a portion of a rim of at least one of the first and second electrodes. The mounting member includes a connection member connected to at least one of the first and second electrodes. The method includes causing the semiconductor light emitting device and a mounting member to face each other, and causing the connection member to contact and join to the at least one of the first and second electrodes using the protruding portion as a guide.
    Type: Application
    Filed: November 16, 2012
    Publication date: June 13, 2013
    Inventors: Hiroshi KATSUNO, Yasuo Ohba, Kei Kaneko, Mitsuhiro Kushibe
  • Publication number: 20130112988
    Abstract: A semiconductor light emitting device includes a first layer including at least one of n-type GaN and n-type AlGaN; a second layer including Mg-containing p-type AlGaN; and a light emitting section provided between the first and second layers. The light emitting section includes barrier layers of Si-containing AlxGa1-x-yInyN (0?x, 0?y, x+y?1), and a well layer provided between the barrier layers and made of GaInN or AlGaInN. The barrier layers have a nearest barrier layer nearest to the second layer among the barrier layers and a far barrier layer. The nearest barrier layer includes a first portion made of Si-containing AlxGa1-x-yInyN (0?x, 0?y, x+y?1), and a second portion provided between the first portion and the second layer and made of AlxGa1-x-yInyN (0?x, 0?y, x+y?1). The Si concentration in the second portion is lower than those in the first portion and in the far barrier layer.
    Type: Application
    Filed: November 8, 2012
    Publication date: May 9, 2013
    Inventors: Kei Kaneko, Yasuo Ohba, Hiroshi Katsuno, Mitsuhiro Kushibe
  • Patent number: 8421085
    Abstract: According to one embodiment, a semiconductor light-emitting device includes a first semiconductor layer of a first conductivity type, a second semiconductor layer of a second conductivity type, a light-emitting layer, a third semiconductor layer and a first electrode. The light-emitting layer is provided between the first and second semiconductor layers. The third semiconductor layer is provided on opposite side of the first semiconductor layer from the light-emitting layer, has a lower impurity concentration than the first semiconductor layer, and includes an opening exposing part of the first semiconductor layer. The first electrode is in contact with the first semiconductor layer through the opening. The third semiconductor layer further includes a rough surface portion which is provided on opposite side from the first semiconductor layer and includes a surface asperity larger than wavelength in the third semiconductor layer of peak wavelength of emission light emitted from the light-emitting layer.
    Type: Grant
    Filed: September 1, 2010
    Date of Patent: April 16, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroshi Katsuno, Yasuo Ohba, Mitsuhiro Kushibe, Kei Kaneko, Shinji Yamada
  • Publication number: 20130069032
    Abstract: According to one embodiment, a semiconductor light emitting device includes a first layer of n-type and a second layer of p-type including a nitride semiconductor, a light emitting unit provided between the first and second layers, a first stacked structure provided between the first layer and the light emitting unit, and a second stacked structure provided between the first layer and the first stacked structure. The light emitting unit includes barrier layers and a well layer provided between the barrier layers. The first stacked structure includes third layers including a nitride semiconductor, and fourth layers stacked with the third layers and including GaInN. The fourth layers have a thinner thickness than the well layer. The second stacked structure includes fifth layers including a nitride semiconductor, and sixth layers stacked with the fifth layers and including GaInN. The sixth layers have a thinner thickness than the well layer.
    Type: Application
    Filed: February 28, 2012
    Publication date: March 21, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Mitsuhiro KUSHIBE, Yasuo OHBA, Hiroshi KATSUNO, Kei KANEKO, Shinji YAMADA
  • Publication number: 20130069033
    Abstract: According to one embodiment, a semiconductor device includes a first layer of n-type including a nitride semiconductor, a second layer of p-type including a nitride semiconductor, a light emitting unit, and a first stacked body. The light emitting unit is provided between the first and second layers. The first stacked body is provided between the first layer and the light emitting unit. The first stacked body includes a plurality of third layers including AlGaInN, and a plurality of fourth layers alternately stacked with the third layers and including GaInN. The first stacked body has a first surface facing the light emitting unit. The first stacked body has a depression provided in the first surface. A part of the light emitting unit is embedded in a part of the depression. A part of the second layer is disposed on the part of the light emitting unit.
    Type: Application
    Filed: February 28, 2012
    Publication date: March 21, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Mitsuhiro KUSHIBE, Yasuo OHBA, Hiroshi KATSUNO, Kei KANEKO, Shinji YAMADA