Patents by Inventor Shuji Nakamura

Shuji Nakamura 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: 8791000
    Abstract: A nonpolar III-nitride film grown on a miscut angle of a substrate, in order to suppress the surface undulations, is provided. The surface morphology of the film is improved with a miscut angle towards an a-axis direction comprising a 0.15° or greater miscut angle towards the a-axis direction and a less than 30° miscut angle towards the a-axis direction.
    Type: Grant
    Filed: January 27, 2014
    Date of Patent: July 29, 2014
    Assignee: The Regents of the University of California
    Inventors: Asako Hirai, Zhongyuan Jia, Makoto Saito, Hisashi Yamada, Kenji Iso, Steven P. DenBaars, Shuji Nakamura, James S. Speck
  • Patent number: 8790943
    Abstract: A method of fabricating an (Al,Ga,In)N laser diode, comprising depositing one or more III-N layers upon a growth substrate at a first temperature, depositing an indium containing laser core at a second temperature upon layers deposited at a first temperature, and performing all subsequent fabrication steps under conditions that inhibit degradation of the laser core, wherein the conditions are a substantially lower temperature than the second temperature.
    Type: Grant
    Filed: August 23, 2012
    Date of Patent: July 29, 2014
    Assignee: The Regents of the University of California
    Inventors: Daniel A. Cohen, Steven P. DenBaars, Shuji Nakamura
  • Patent number: 8779308
    Abstract: A key switch device including a key top; a pair of link members connected to the key top and interlocked with each other to guide a vertical motion of the key top; a switch mechanism including a membrane sheet switch capable of opening and closing a contact section of an electrical circuit in accordance with the vertical motion of the key top; a flexible thin film sheet attached to the membrane sheet switch; and a housing attached to the thin film sheet, the housing adapted to connect the link members to the thin film sheet.
    Type: Grant
    Filed: February 7, 2012
    Date of Patent: July 15, 2014
    Assignee: Fujitsu Component Limited
    Inventors: Akihiko Takemae, Norio Endo, Shuji Nakamura, Tamotsu Koike, Takeshi Nishino
  • Publication number: 20140191244
    Abstract: A method of controlled p-type conductivity in (Al,In,Ga,B)N semiconductor crystals. Examples include {10 11} GaN films deposited on {100} MgAl2O4 spinel substrate miscut in the <011> direction. Mg atoms may be intentionally incorporated in the growing semipolar nitride thin film to introduce available electronic states in the band structure of the semiconductor crystal, resulting in p-type conductivity. Other impurity atoms, such as Zn or C, which result in a similar introduction of suitable electronic states, may also be used.
    Type: Application
    Filed: March 12, 2014
    Publication date: July 10, 2014
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: John F. Kaeding, Hitoshi Sato, Michael Iza, Hirokuni Asamizu, Hong Zhong, Steven P. DenBaars, Shuji Nakamura
  • Publication number: 20140190403
    Abstract: A method of growing high-quality, group-III nitride, bulk single crystals. The group III-nitride bulk crystal is grown in an autoclave in supercritical ammonia using a source material or nutrient that is a group III-nitride polycrystals or group-III metal having a grain size of at least 10 microns or more and a seed crystal that is a group-III nitride single crystal. The group III-nitride polycrystals may be recycled from previous ammonothermal process after annealing in reducing gas at more then 600° C. The autoclave may include an internal chamber that is filled with ammonia, wherein the ammonia is released from the internal chamber into the autoclave when the ammonia attains a supercritical state after the heating of the autoclave, such that convection of the supercritical ammonia transfers source materials and deposits the transferred source materials onto seed crystals, but undissolved particles of the source materials are prevented from being transferred and deposited on the seed crystals.
    Type: Application
    Filed: March 12, 2014
    Publication date: July 10, 2014
    Applicants: JAPAN SCIENCE AND TECHNOLOGY AGENCY, THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Kenji Fujito, Tadao Hashimoto, Shuji Nakamura
  • Patent number: 8772758
    Abstract: A method for fabricating a III-nitride based semiconductor device, including (a) growing one or more buffer layers on or above a semi-polar or non-polar GaN substrate, wherein the buffer layers are semi-polar or non-polar III-nitride buffer layers; and (b) doping the buffer layers so that a number of crystal defects in III-nitride device layers formed on or above the doped buffer layers is not higher than a number of crystal defects in III-nitride device layers formed on or above one or more undoped buffer layers. The doping can reduce or prevent formation of misfit dislocation lines and additional threading dislocations. The thickness and/or composition of the buffer layers can be such that the buffer layers have a thickness near or greater than their critical thickness for relaxation. In addition, one or more (AlInGaN) or III-nitride device layers can be formed on or above the buffer layers.
    Type: Grant
    Filed: May 14, 2012
    Date of Patent: July 8, 2014
    Assignee: The Regents of the University of California
    Inventors: Matthew T. Hardy, Po Shan Hsu, Steven P. DenBaars, James S. Speck, Shuji Nakamura
  • Patent number: 8772792
    Abstract: An LED having a p-type layer of material with an associated p-contact, an n-type layer of material with an associated n-contact and an active region between the p-type layer and the n-type layer, includes a roughened emitting-side surface to further enhance light extraction.
    Type: Grant
    Filed: August 23, 2013
    Date of Patent: July 8, 2014
    Assignee: Cree, Inc.
    Inventors: Steven P. DenBaars, Shuji Nakamura, Max Batres
  • Publication number: 20140183579
    Abstract: A method for improved growth of a semipolar (Al,In,Ga,B)N semiconductor thin film using an intentionally miscut substrate. Specifically, the method comprises intentionally miscutting a substrate, loading a substrate into a reactor, heating the substrate under a flow of nitrogen and/or hydrogen and/or ammonia, depositing an InxGa1-xN nucleation layer on the heated substrate, depositing a semipolar nitride semiconductor thin film on the InxGa1-xN nucleation layer, and cooling the substrate under a nitrogen overpressure.
    Type: Application
    Filed: January 2, 2013
    Publication date: July 3, 2014
    Applicants: Japan Science and Technology Agency, The Regents of the University of California
    Inventors: John F. Kaeding, Dong-Seon Lee, Michael Iza, Troy J. Baker, Hitoshi Sato, Benjamin A. Haskell, James S. Speck, Steven P. DenBaars, Shuji Nakamura
  • Patent number: 8766296
    Abstract: A gallium nitride (GaN) based light emitting diode (LED), wherein light is extracted through a nitrogen face (N-face) of the LED and a surface of the N-face is roughened into one or more hexagonal shaped cones. The roughened surface reduces light reflections occurring repeatedly inside the LED, and thus extracts more light out of the LED. The surface of the N-face is roughened by an anisotropic etching, which may comprise a dry etching or a photo-enhanced chemical (PEC) etching.
    Type: Grant
    Filed: October 8, 2009
    Date of Patent: July 1, 2014
    Assignees: The Regents of the University of California, Japan Science and Technology Agency
    Inventors: Tetsuo Fujii, Yan Gao, Evelyn L. Hu, Shuji Nakamura
  • Patent number: 8762995
    Abstract: A computing system includes a plurality of computing units, a tiered storage unit including a first storage medium and a second storage medium having a transfer rate lower than that of the first storage medium, and connected to a plurality of the computing units; and a system management unit connected to a plurality of the computing units and the tiered storage unit. The system management unit creates a computation job execution schedule for a plurality of the computing units or obtains the computation job execution schedule from other unit in the computing system, plans a data migration in the tiered storage unit according to the execution schedule using a predetermined method, and instructs the tiered storage unit to migrate a data based on the plan.
    Type: Grant
    Filed: February 28, 2008
    Date of Patent: June 24, 2014
    Assignee: Hitachi, Ltd.
    Inventors: Hirotoshi Akaike, Kazuhisa Fujimoto, Shuji Nakamura
  • Patent number: 8759705
    Abstract: A push button-type switch device includes a pair of fixed contacts, an operable member to be pushed, an actuating member elastically deformable upon the operable member being pushed, a movable contact which short-circuits the pair of fixed contacts due to elastic deformation of the actuating member, and a limiting part arranged to limit a direction in which the operable member moves and making the operable member move in a fixed orientation. The limiting part includes a pair of link members that engage with each other, one ends of the link members rotatably supported by the base portion, and the other ends thereof slidably supported by the operable member. This produces a good click irrespective of a position where the operable member is operated.
    Type: Grant
    Filed: January 31, 2012
    Date of Patent: June 24, 2014
    Assignee: Fujitsu Component Limited
    Inventors: Katsuya Funakoshi, Shuji Nakamura, Takeshi Nishino, Junichi Maruyama, Tamotsu Koike
  • Patent number: 8761218
    Abstract: A semipolar plane III-nitride semiconductor-based laser diode or light emitting diode, comprising a semipolar Indium containing multiple quantum wells for emitting light, having Aluminum containing quantum well barriers, wherein the Indium containing multiple quantum well and Aluminum containing barriers are grown in a semipolar orientation on a semipolar plane.
    Type: Grant
    Filed: April 5, 2011
    Date of Patent: June 24, 2014
    Assignee: The Regents of the University of California
    Inventors: You-Da Lin, Hiroaki Ohta, Shuji Nakamura, Steven P. DenBaars, James S. Speck
  • Publication number: 20140167059
    Abstract: A method of performing a photoelectrochemical (PEC) etch on an exposed surface of a semipolar {20-2-1} III-nitride semiconductor, for improving light extraction from and for enhancing external efficiency of one or more active layers formed on or above the semipolar {20-2-1} III-nitride semiconductor.
    Type: Application
    Filed: August 30, 2013
    Publication date: June 19, 2014
    Inventors: Chung-Ta Hsu, Chia-Yen Huang, Yuji Zhao, Shih-Chieh Haung, Daniel F. Feezell, Steven P. DenBaars, Shuji Nakamura, James S. Speck
  • Publication number: 20140151738
    Abstract: A light emitting diode (LED) includes a p-type layer of material, an n-type layer of material and an active layer between the p-type layer and the n-type layer. A roughened layer of transparent material is adjacent one of the p-type layer of material and the n-type layer of material. The roughened layer of transparent material has a refractive index close to or substantially the same as the refractive index of the material adjacent the layer of transparent material, and may be a transparent oxide material or a transparent conducting material. An additional layer of conductive material may be between the roughened layer and the n-type or p-type layer.
    Type: Application
    Filed: February 5, 2014
    Publication date: June 5, 2014
    Applicant: CREE, INC.
    Inventors: STEVEN P. DENBAARS, JAMES IBBETSON, SHUJI NAKAMURA
  • Publication number: 20140151634
    Abstract: A light emitting diode structure of (Al,Ga,In)N thin films grown on a gallium nitride (GaN) semipolar substrate by metal organic chemical vapor deposition (MOCVD) that exhibits reduced droop. The device structure includes a quantum well (QW) active region of two or more periods, n-type superlattice layers (n-SLs) located below the QW active region, and p-type superlattice layers (p-SLs) above the QW active region. The present invention also encompasses a method of fabricating such a device.
    Type: Application
    Filed: February 6, 2014
    Publication date: June 5, 2014
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Shuji Nakamura, Steven P. DenBaars, Shinichi Tanaka, Daniel F. Feezell, Yuji Zhao, Chih-Chien Pan
  • Publication number: 20140138679
    Abstract: A nonpolar III-nitride film grown on a miscut angle of a substrate, in order to suppress the surface undulations, is provided. The surface morphology of the film is improved with a miscut angle towards an a-axis direction comprising a 0.15° or greater miscut angle towards the a-axis direction and a less than 30° miscut angle towards the a-axis direction.
    Type: Application
    Filed: January 27, 2014
    Publication date: May 22, 2014
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Asako Hirai, Zhongyuan Jia, Makoto Saito, Hisashi Yamada, Kenji Iso, Steven P. DenBaars, Shuji Nakamura, James S. Speck
  • Patent number: 8729671
    Abstract: A method for fabricating a high quality freestanding nonpolar and semipolar nitride substrate with increased surface area, comprising stacking multiple films by growing the films one on top of each other with different and non-orthogonal growth directions.
    Type: Grant
    Filed: December 15, 2011
    Date of Patent: May 20, 2014
    Assignee: The Regents of the University of California
    Inventors: Asako Hirai, James S. Speck, Steven P. DenBaars, Shuji Nakamura
  • Patent number: 8726755
    Abstract: In a shift lever device, a first-link is held at a permitting-position due to a release button being operated. Therefore, when a shift lever is operated from a “P” shift position, when a second-link is pushed toward a vehicle right side by the shift lever, even if a magnet is not energized, the second-link is rotated in a state where sliding of the first-link toward a vehicle right is impeded. Operation of the shift lever from the “P” shift position is thereby forcibly permitted. Here, the first-link is disposed at the permitting-position that is an initial-position, and, due to the release button being operated, the first-link is held at the permitting-position. Therefore, there is no need to move the first-link by operation of the release button, and the operation load and operation stroke of the release button can be made to be small.
    Type: Grant
    Filed: October 19, 2011
    Date of Patent: May 20, 2014
    Assignee: Kabushiki Kaisha Tokai-Rika-Denki-Seisakusho
    Inventors: Shuji Nakamura, Hideaki Ito
  • Publication number: 20140126599
    Abstract: An (Al,In,B,Ga)N or III-nitride based laser diode epitaxially grown on orientations other than a c-plane orientation, namely various semipolar and nonpolar orientations, and having polished facets. The semipolar orientation may be a semipolar (11-22), (11-2-2), (101-1), (10-1-1), (20-21), (20-2-1), (30-31) or (30-3-1) orientation, and the nonpolar orientation may be a nonpolar (10-10) or (11-20) orientation. The facets are chemically mechanically or mechanically polished.
    Type: Application
    Filed: October 29, 2013
    Publication date: May 8, 2014
    Inventors: Po Shan Hsu, Jeremiah J. Weaver, Steven P. DenBaars, James S. Speck S. Speck, Shuji Nakamura
  • Publication number: 20140116326
    Abstract: Reactor designs for use in ammonothermal growth of group-III nitride crystals. Internal heating is used to enhance and/or engineer fluid motion, gas mixing, and the ability to create solubility gradients within a vessel used for the ammonothermal growth of group-III nitride crystals. Novel baffle designs are used for control and improvement of continuous fluid motion within a vessel used for the ammonothermal growth of group-III nitride crystals.
    Type: Application
    Filed: January 7, 2014
    Publication date: May 1, 2014
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Siddha Pimputkar, Derrick Shane Kamber, James S. Speck, Shuji Nakamura