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: 11916533
    Abstract: Surface acoustic wave devices and related methods. In some embodiments, a surface acoustic wave device for providing resonance of a surface acoustic wave having a wavelength ? can include a quartz substrate and a piezoelectric plate formed from LiTaO3 or LiNbO3 disposed over the quartz substrate. The piezoelectric plate can have a thickness greater than 2?. The surface acoustic wave device can further include an interdigital transducer electrode formed over the piezoelectric plate. The interdigital transducer electrode can have a mass density ? in a range 1.50 g/cm3<??6.00 g/cm3, 6.00 g/cm3<??12.0 g/cm3, or 12.0 g/cm3<??23.0 g/cm3, and a thickness greater than 0.148?, greater than 0.079?, or greater than 0.036?, respectively.
    Type: Grant
    Filed: June 7, 2022
    Date of Patent: February 27, 2024
    Inventors: Michio Kadota, Shuji Tanaka, Hiroyuki Nakamura
  • Publication number: 20230420617
    Abstract: A nitride-based ultraviolet light emitting diode (UVLED) with an ultraviolet transparent contact (UVTC). The nitride-based UVLED is an alloy composition of (Ga, Al, In, B)N semiconductors, and the UVTC is composed of an oxide with a bandgap larger than that emitted in an active region of the nitride-based UVLED, wherein the oxide is an alloy composition of (Ga, Al, In, B, Mg, Fe, Si, Sn)O semiconductors, such as Ga2O3.
    Type: Application
    Filed: October 29, 2021
    Publication date: December 28, 2023
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Michael Iza, Matthew S. Wong, Steven P. DenBaars, Shuji Nakamura
  • Publication number: 20230369538
    Abstract: A multilayer structure comprising regions of higher aluminum (Al) composition as compared to adjacent layers, in combination with an undulating active region and controlled buffer layer crystal quality, promotes radiative recombination and improves the performance and efficiency of ultraviolet (UV) or far-UV light-emitting diodes (LEDs), laser diode (LDs), or other light emitting devices.
    Type: Application
    Filed: May 1, 2023
    Publication date: November 16, 2023
    Applicant: The Regents of the University of California
    Inventors: Michael Wang, Christian J. Zollner, Yifan Yao, Michael Iza, Shuji Nakamura
  • Patent number: 11805986
    Abstract: A flexible tube insertion apparatus includes a flexible insertion section to be inserted into a subject and bent by a reaction force from the subject, a variable stiffness unit provided in the insertion section and configured to change a stiffness of the insertion section, and a shape detector configured to detect a bent shape of the insertion section. The apparatus further includes a force specifier configured to acquire a distribution of the reaction force on a distal side from a predetermined point in the bent shape and specify a maximum reaction force position, and a stiffness controller configured to control a stiffness of the variable stiffness unit so as to increase a stiffness of the variable stiffness unit between the predetermined point and the maximum reaction force position.
    Type: Grant
    Filed: August 28, 2020
    Date of Patent: November 7, 2023
    Assignee: OLYMPUS CORPORATION
    Inventors: Shuji Nakamura, Takeshi Takahashi, Yuichi Ikeda
  • Patent number: 11784454
    Abstract: In an example, the present invention provides a high intensity pulse laser generation system. The system has a variety of elements. The system has an optical cavity maintained in a vacuum, e.g., 300 Torr and less. In an example, the optical cavity is configured to increase an intensity of a laser beam comprising a pulse from a first energy power intensity to a second higher energy power intensity propagating on a first optical path configured within the optical cavity by circulating or reciprocating at least a portion of the laser beam.
    Type: Grant
    Filed: December 22, 2022
    Date of Patent: October 10, 2023
    Assignee: Blue Laser Fusion, Inc.
    Inventors: Shuji Nakamura, Hiroaki Ohta
  • Publication number: 20230307579
    Abstract: A method to fabricate micro-size III-nitride light emitting diodes (?LEDs) with an epitaxial tunnel junction comprised of a p+GaN layer, an InxAlyGazN insertion layer, and an n+GaN layer, grown using metalorganic chemical vapor deposition (MOCVD), wherein the ?LEDs have a low forward the GaN layers, which reduces a depletion width of the tunnel junction and increases the tunneling probability. The ?LEDs are fabricated with dimensions that vary from 25 to 10,000 ?m2. It was found that the InxAlyGazN insertion layer can reduce the forward voltage at 20 A/cm2 by at least 0.6 V. The tunnel junction ?LEDs with an n-type and p-type InxAlyGazN insertion layer had a low forward voltage at 20 A/cm2 that was very stable. At dimensions smaller than 1600 ?m2, the low forward voltage is less than 3.2 V.
    Type: Application
    Filed: August 11, 2021
    Publication date: September 28, 2023
    Applicant: The Regents of the University of California
    Inventors: Panpan Li, Hongjian Li, Michael Iza, Shuji Nakamura, Steven P. DenBaars
  • Publication number: 20230275185
    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: Application
    Filed: May 2, 2023
    Publication date: August 31, 2023
    Applicant: The Regents of the University of California
    Inventors: Tetsuo Fujii, Yan Gao, Evelyn L. Hu, Shuji Nakamura
  • Publication number: 20230268462
    Abstract: A fully transparent UV LED or far-UV LED is disclosed, in which all semiconductor layers except the active region are transparent to the radiation emitted in the active region. The key technology enabling this invention is the transparent tunnel junction, which replaces the optically absorbing p-GaN and metal mirror p-contact currently found in all commercially available UV LEDs. The tunnel junction also enables the use of a second n-AlGaN current spreading layer above the active region (on the p-side of the device) similar to the current spreading layer already found below the active region (on the n-side of the device). Therefore, small-area and/or remote p- and n-contacts can be used, and light can be extracted from both the top-side and bottom-side of the device. This fully transparent semiconductor device can then be packaged using transparent materials into a fully transparent UV LED or far-UV LED with high brightness and efficiency.
    Type: Application
    Filed: July 9, 2021
    Publication date: August 24, 2023
    Applicant: The Regents of the University of California
    Inventors: Christian J. Zollner, Michael Iza, James S. Speck, Steven P. DenBaars, Shuji Nakamura
  • Patent number: 11735419
    Abstract: A method for protecting a semiconductor film comprised of one or more layers during processing. The method includes placing a surface of the semiconductor film in direct contact with a surface of a protective covering, such as a separate substrate piece, that forms an airtight or hermetic seal with the surface of the semiconductor film, so as to reduce material degradation and evaporation in the semiconductor film. The method includes processing the semiconductor film under some conditions, such as a thermal annealing and/or controlled ambient, which might cause the semiconductor film's evaporation or degradation without the protective covering.
    Type: Grant
    Filed: January 24, 2020
    Date of Patent: August 22, 2023
    Assignee: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Christian J. Zollner, Michael Iza, James S. Speck, Shuji Nakamura, Steven P. DenBaars
  • Publication number: 20230187573
    Abstract: A III-nitride LED with simultaneous visible and ultraviolet (UV) emission, in which the visible emission is due to conventional InGaN active region mechanisms and the UV emission occurs due to Auger carrier injection into a UV light emitting region, such as impurity-doped AlGaN. The primary application for the III-nitride LED is general airborne pathogen inactivation to prevent the transmission of airborne-mediated pathogens while being safe for humans.
    Type: Application
    Filed: May 28, 2021
    Publication date: June 15, 2023
    Applicant: The Regents of the University of California
    Inventors: Vincent Rienzi, Christian J. Zollner, Steven P. DenBaars, Shuji Nakamura
  • Patent number: 11677044
    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: March 18, 2021
    Date of Patent: June 13, 2023
    Assignee: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Tetsuo Fujii, Yan Gao, Evelyn L. Hu, Shuji Nakamura
  • Publication number: 20230051845
    Abstract: A p-n junction based III-nitride device in which the p-type layers adjacent to the n-type layers are activated by thermal annealing with a porous n-type tunnel junction layer or layers. The porosity of the n-type tunnel junction layer(s) allows for gas exchange to occur, allowing efficient p-type nitride semiconductor activation. This porosification and activation step can be inserted wherever desired into an existing fabrication process for an LED, laser diode, or any other nitride semiconductor device. In one example, the device comprises multiple LED structures grown successively, separated by tunnel junctions and the buried p-type layers are activated by thermal annealing with adjacent porous n-type layers. Using this method, efficient monolithic multi-color LEDs can be formed.
    Type: Application
    Filed: January 21, 2021
    Publication date: February 16, 2023
    Applicant: The Regents of the University of California
    Inventors: Christian J. Zollner, Shuji Nakamura
  • Publication number: 20230015695
    Abstract: The present invention provide a puncture instrument capable of administering (supplying) a drug solution. The puncture instrument includes a puncture tip section (2); a first tubular body (3) connected to the puncture tip section (2) at the distal end; and an outer tubular body (5) at least partially covering the first tubular body (3). The first tubular body (3) is formed to be rotatable around an axis along the longitudinal direction. The first tubular body (3) has an outer diameter smaller than an inner diameter of the outer tubular body (5). A drug solution supply path (5a) is provided on the outside of the first tubular body (3).
    Type: Application
    Filed: June 28, 2022
    Publication date: January 19, 2023
    Inventors: Shuji NAKAMURA, Ken MASAMUNE, Kohei MIKI, Katsuyuki SADO, Hirokazu TAKAGAWA, Fumiya IWASHIMA, Akihiro NABESHIMA
  • Patent number: 11552452
    Abstract: An optoelectronic device grown on a miscut of GaN, wherein the miscut comprises a semi-polar GaN crystal plane (of the GaN) miscut x degrees from an m-plane of the GaN and in a c-direction of the GaN, where ?15<x<?1 and 1<x<15 degrees.
    Type: Grant
    Filed: January 26, 2018
    Date of Patent: January 10, 2023
    Assignee: The Regents of the University of California
    Inventors: Po Shan Hsu, Kathryn M. Kelchner, Robert M. Farrell, Daniel A. Haeger, Hiroaki Ohta, Anurag Tyagi, Shuji Nakamura, Steven P. DenBaars, James S. Speck
  • Patent number: 11532922
    Abstract: A Vertical Cavity Surface Emitting Laser (VCSEL) including a light emitting III-nitride active region including quantum wells (QWs), wherein each of the quantum wells have a thickness of more than 8 nm, a cavity length of at least 7 ?, or at least 20 ?, where lambda is a peak wavelength of the light emitted from the active region, layers with reduced surface roughness, a tunnel junction intracavity contact. The VCSEL is flip chip bonded using In—Au bonding. This is the first report of a VCSEL capable of continuous wave operation.
    Type: Grant
    Filed: October 2, 2018
    Date of Patent: December 20, 2022
    Assignee: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Charles Forman, SeungGeun Lee, Erin C. Young, Jared Kearns, Steven P. DenBaars, James S. Speck, Shuji Nakamura
  • Patent number: 11478273
    Abstract: The present invention provide a puncture instrument capable of administering (supplying) a drug solution. The puncture instrument includes a puncture tip section (2); a first tubular body (3) connected to the puncture tip section (2) at the distal end; and an outer tubular body (5) at least partially covering the first tubular body (3). The first tubular body (3) is formed to be rotatable around an axis along the longitudinal direction. The first tubular body (3) has an outer diameter smaller than an inner diameter of the outer tubular body (5). A drug solution supply path (5a) is provided on the outside of the first tubular body (3).
    Type: Grant
    Filed: January 31, 2018
    Date of Patent: October 25, 2022
    Assignee: TRANSELL CO., LTD.
    Inventors: Shuji Nakamura, Ken Masamune, Kohei Miki, Katsuyuki Sado, Hirokazu Takagawa, Fumiya Iwashima, Akihiro Nabeshima
  • Patent number: 11411137
    Abstract: A III-nitride optoelectronic device includes at least one n-type layer, an active region grown on or above the n-type layer, at least one p-type layer grown on or above the active region, and a tunnel junction grown on or above the p-type layer. A conductive oxide may be wafer bonded on or above the tunnel junction, wherein the conductive oxide comprises a transparent conductor and may contain light extraction features on its non-bonded face. The tunnel junction also enables monolithic incorporation of electrically-injected and optically-pumped III-nitride layers, wherein the optically-pumped III-nitride layers comprise high-indium-content III-nitride layers formed as quantum wells (QWs) that are grown on or above the tunnel junction. The optically-pumped high-indium-content III-nitride layers emit light at a longer wavelength than the electrically-injected III-nitride layers.
    Type: Grant
    Filed: February 6, 2017
    Date of Patent: August 9, 2022
    Assignee: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Asad J. Mughal, Stacy J. Kowsz, Robert M. Farrell, Benjamin P. Yonkee, Erin C. Young, Christopher D. Pynn, Tal Margalith, James S. Speck, Shuji Nakamura, Steven P. DenBaars
  • Publication number: 20220239068
    Abstract: Vertical Cavity Surface Emitting Laser (VCSEL) configurations are disclosed. In a first example, the VCSEL includes a III-Nitride active region between a p-type III-Nitride layer and an n-type III-Nitride layer; and a curved minor on or above the p-type III-Nitride layer. The curved mirror can be formed in a III-Nitride layer or a Transparent Oxide (TO) material and enables the formation of a long VCSEL cavity that improves VCSEL lifetime, VCSEL output power, VCSEL power efficiency and VCSEL reliability. In a second example, the VCSEL has an active region with a high indium content. In a third example, the VCSEL is transparent.
    Type: Application
    Filed: May 28, 2020
    Publication date: July 28, 2022
    Applicant: The Regents of the University of California
    Inventors: Jared Kearns, Daniel A. Cohen, Joonho Back, Nathan Palmquist, Tal Margalith, Steven P. DenBaars, Shuji Nakamura
  • Publication number: 20220181513
    Abstract: A hybrid growth method for III-nitride tunnel junction devices uses metal-organic chemical vapor deposition (MOCVD) to grow one or more light-emitting or light-absorbing structures and ammonia-assisted or plasma-assisted molecular beam epitaxy (MBE) to grow one or more tunnel junctions. Unlike p-type gallium nitride (p-GaN) grown by MOCVD, p-GaN grown by MBE is conductive as grown, which allows for its use in a tunnel junction. Moreover, the doping limits of MBE materials are higher than MOCVD materials. The tunnel junctions can be used to incorporate multiple active regions into a single device. In addition, n-type GaN (n-GaN) can be used as a current spreading layer on both sides of the device, eliminating the need for a transparent conductive oxide (TCO) layer or a silver (Au) mirror.
    Type: Application
    Filed: December 1, 2021
    Publication date: June 9, 2022
    Applicant: The Regents of the University of California
    Inventors: Erin C. Young, Benjamin P. Yonkee, John T. Leonard, Tal Margalith, James S. Speck, Steven P. DenBaars, Shuji Nakamura
  • Patent number: 11348908
    Abstract: A flip chip III-Nitride LED which utilizes a dielectric coating backed by a metallic reflector (e.g., aluminum or silver). High reflectivity and low resistance contacts for optoelectronic devices. Low ESD rating optoelectronic devices. A VCSEL comprising a tunnel junction for current and optical confinement.
    Type: Grant
    Filed: August 17, 2017
    Date of Patent: May 31, 2022
    Assignee: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Benjamin P. Yonkee, Erin C. Young, James S. Speck, Steven P. DenBaars, Shuji Nakamura