Patents by Inventor Steven P. Denbaars

Steven P. Denbaars 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).

  • (Al,In,B,Ga)N BASED SEMIPOLAR AND NONPOLAR LASER DIODES WITH POLISHED FACETS
    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
  • Method for conductivity control of (Al,In,Ga,B)N
    Patent number: 8709925
    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: Grant
    Filed: April 5, 2012
    Date of Patent: April 29, 2014
    Assignee: The Regents of the University of California
    Inventors: John F. Kaeding, Hitoshi Sato, Michael Iza, Hirokuni Asamizu, Hong Zhong, Steven P. DenBaars, Shuji Nakamura
  • HIGH BRIGHTNESS LIGHT EMITTING DIODE COVERED BY ZINC OXIDE LAYERS ON MULTIPLE SURFACES GROWN IN LOW TEMPERATURE AQUEOUS SOLUTION
    Publication number: 20140103361
    Abstract: A high brightness III-Nitride based Light Emitting Diode (LED), comprising multiple surfaces covered by Zinc Oxide (ZnO) layers, wherein the ZnO layers are grown in a low temperature aqueous solution and each have a (0001) c-orientation and a top surface that is a (0001) plane.
    Type: Application
    Filed: December 19, 2013
    Publication date: April 17, 2014
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Daniel B. Thompson, Jacob J. Richardson, Ingrid Koslow, Jun Seok Ha, Frederick F. Lange, Steven P. DenBaars, Shuji Nakamura
  • III-V nitride-based thermoelectric device
    Patent number: 8692105
    Abstract: A method to suppress thermal conductivities of nitride films by using stacking faults and/or nano-scale In-composition fluctuation(s). Therefore, the present invention reduces thermal conductivity of nitride while keeping electrical conductivity high. In addition, In composition fluctuations can enhance the Seebeck coefficient through thermionic emission. The present invention further discloses a nitride based (e.g. GaN) thermoelectric lateral device with a short length.
    Type: Grant
    Filed: April 18, 2011
    Date of Patent: April 8, 2014
    Assignee: The Regents of the University of California
    Inventors: Hiroaki Ohta, Alexander Sztein, Steven P. DenBaars, Shuji Nakamura
  • Planar nonpolar group-III nitride films grown on miscut substrates
    Patent number: 8691671
    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 ?-axis direction comprising a 0.15° or greater miscut angle towards the ?-axis direction and a less than 30° miscut angle towards the ?-axis direction.
    Type: Grant
    Filed: March 22, 2012
    Date of Patent: April 8, 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
  • OPTICAL DESIGNS FOR HIGH-EFFICACY WHITE-LIGHT EMITTING DIODES
    Publication number: 20140091349
    Abstract: A method for increasing the luminous efficacy of a white light emitting diode (WLED), comprising introducing optically functional interfaces between an LED die and a phosphor, and between the phosphor and an outer medium, wherein at least one of the interfaces between the phosphor and the LED die provides a reflectance for light emitted by the phosphor away from the outer medium and a transmittance for light emitted by the LED die. Thus, a WLED may comprise a first material which surrounds an LED die, a phosphor layer, and at least one additional layer or material which is transparent for direct LED emission and reflective for the phosphor emission, placed between the phosphor layer and the first material which surrounds the LED die.
    Type: Application
    Filed: December 6, 2013
    Publication date: April 3, 2014
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Frederic S. Diana, Steven P. DenBaars, Shuji Nakamura
  • Low droop light emitting diode structure on gallium nitride semipolar substrates
    Patent number: 8686397
    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: Grant
    Filed: June 11, 2012
    Date of Patent: April 1, 2014
    Assignee: The Regents of the University of California
    Inventors: Shuji Nakamura, Steven P. DenBaars, Shinichi Tanaka, Daniel F. Feezell, Yuji Zhao, Chih-Chien Pan
  • Technique for the growth and fabrication of semipolar (Ga,Al,In,B)N thin films, heterostructures, and devices
    Patent number: 8686466
    Abstract: A method for growth and fabrication of semipolar (Ga, Al, In, B)N thin films, heterostructures, and devices, comprising identifying desired material properties for a particular device application, selecting a semipolar growth orientation based on the desired material properties, selecting a suitable substrate for growth of the selected semipolar growth orientation, growing a planar semipolar (Ga, Al, In, B)N template or nucleation layer on the substrate, and growing the semipolar (Ga, Al, In, B)N thin films, heterostructures or devices on the planar semipolar (Ga, Al, In, B)N template or nucleation layer. The method results in a large area of the semipolar (Ga, Al, In, B)N thin films, heterostructures, and devices being parallel to the substrate surface.
    Type: Grant
    Filed: November 23, 2010
    Date of Patent: April 1, 2014
    Assignees: The Regents of the University of California, Japan Science and Technology Agency
    Inventors: Robert M. Farrell, Jr., Troy J. Baker, Arpan Chakraborty, Benjamin A. Haskell, P. Morgan Pattison, Rajat Sharma, Umesh K. Mishra, Steven P. DenBaars, James S. Speck, Shuji Nakamura
  • Roughened high refractive index layer/LED for high light extraction
    Patent number: 8674375
    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: Grant
    Filed: July 21, 2005
    Date of Patent: March 18, 2014
    Assignee: Cree, Inc.
    Inventors: Steven P. Denbaars, James Ibbetson, Shuji Nakamura
  • Optoelectronic device based on non-polar and semi-polar aluminum indium nitride and aluminum indium gallium nitride alloys
    Patent number: 8653503
    Abstract: A high-power and high-efficiency light emitting device with emission wavelength (?peak) ranging from 280 nm to 360 nm is fabricated. The new device structure uses non-polar or semi-polar AlInN and AlInGaN alloys grown on a non-polar or semi-polar bulk GaN substrate.
    Type: Grant
    Filed: December 18, 2012
    Date of Patent: February 18, 2014
    Assignee: The Regents of the University of California
    Inventors: Roy B. Chung, Zhen Chen, James S. Speck, Steven P. DenBaars, Shuji Nakamura
  • Hexagonal wurtzite type epitaxial layer possessing a low alkali-metal concentration and method of creating the same
    Patent number: 8647967
    Abstract: A method of obtaining a hexagonal würtzite type epitaxial layer with a low impurity concentration of alkali-metal by using a hexagonal würtzite substrate possessing a higher impurity concentration of alkali-metal, wherein a surface of the substrate upon which the epitaxial layer is grown has a crystal plane which is different from the c-plane.
    Type: Grant
    Filed: May 28, 2009
    Date of Patent: February 11, 2014
    Assignee: The Regents of the University of California
    Inventors: Makoto Saito, Shin-Ichiro Kawabata, Derrick S. Kamber, Steven P. DenBaars, James S. Speck, Shuji Nakamura
  • In-situ defect reduction techniques for nonpolar and semipolar (Al, Ga, In)N
    Patent number: 8643024
    Abstract: A method for growing reduced defect density planar gallium nitride (GaN) films is disclosed. The method includes the steps of (a) growing at least one silicon nitride (SiNx) nanomask layer over a GaN template, and (b) growing a thickness of a GaN film on top of the SiNx nanomask layer.
    Type: Grant
    Filed: December 20, 2011
    Date of Patent: February 4, 2014
    Assignee: The Regents of the University of California
    Inventors: Arpan Chakraborty, Kwang-Choong Kim, James S. Speck, Steven P. DenBaars, Umesh K. Mishra
  • High brightness light emitting diode covered by zinc oxide layers on multiple surfaces grown in low temperature aqueous solution
    Patent number: 8637334
    Abstract: A high brightness III-Nitride based Light Emitting Diode (LED), comprising multiple surfaces covered by Zinc Oxide (ZnO) layers, wherein the ZnO layers are grown in a low temperature aqueous solution and each have a (0001) c-orientation and a top surface that is a (0001) plane.
    Type: Grant
    Filed: November 3, 2010
    Date of Patent: January 28, 2014
    Assignee: The Regents of the University of California
    Inventors: Daniel B. Thompson, Jacob J. Richardson, Ingrid Koslow, Jun Seok Ha, Steven P. DenBaars, Shuji Nakamura, Maryann E. Lange
  • STRUCTURE AND METHOD FOR THE FABRICATION OF A GALLIUM NITRIDE VERTICAL CAVITY SURFACE EMITTING LASER
    Publication number: 20140023102
    Abstract: A III-Nitride based Vertical Cavity Surface Emitting Laser (VCSEL), wherein a cavity length of the VCSEL is controlled by etching.
    Type: Application
    Filed: July 22, 2013
    Publication date: January 23, 2014
    Inventors: Casey O. Holder, Daniel F. Feezell, Steven P. DenBaars, James S. Speck, Shuji Nakamura
  • Optical designs for high-efficacy white-light emitting diodes
    Patent number: 8624281
    Abstract: A method for increasing the luminous efficacy of a white light emitting diode (WLED), comprising introducing optically functional interfaces between an LED die and a phosphor, and between the phosphor and an outer medium, wherein at least one of the interfaces between the phosphor and the LED die provides a reflectance for light emitted by the phosphor away from the outer medium and a transmittance for light emitted by the LED die. Thus, a WLED may comprise a first material which surrounds an LED die, a phosphor layer, and at least one additional layer or material which is transparent for direct LED emission and reflective for the phosphor emission, placed between the phosphor layer and the first material which surrounds the LED die.
    Type: Grant
    Filed: December 21, 2010
    Date of Patent: January 7, 2014
    Assignee: The Regents of the University of California
    Inventors: Frederic S. Diana, Steven P. DenBaars, Shuji Nakamura
  • LED WITH SURFACE ROUGHENING
    Publication number: 20130341663
    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: Application
    Filed: August 23, 2013
    Publication date: December 26, 2013
    Applicant: Cree, Inc.
    Inventors: Steven P. DenBaars, Shuji Nakamura, Max Batres
  • LIGHT EMITTING DIODE STRUCTURE UTILIZING ZINC OXIDE NANOROD ARRAYS ON ONE OR MORE SURFACES, AND A LOW COST METHOD OF PRODUCING SUCH ZINC OXIDE NANOROD ARRAYS
    Publication number: 20130328012
    Abstract: A method of fabricating a Light Emitting Diode with improved light extraction efficiency, comprising depositing a plurality of Zinc Oxide (ZnO) nanorods on one or more surfaces of a III-Nitride based LED, by growing the ZnO nanorods from an aqueous solution, wherein the surfaces are different from c-plane surfaces of III-Nitride and transmit light generated by the LED.
    Type: Application
    Filed: August 19, 2013
    Publication date: December 12, 2013
    Applicant: The Regents of the University of California
    Inventors: Jacob J. Richardson, Daniel B. Thompson, Ingrid Koslow, Jun-Seok Ha, Frederick F. Lange, Steven P. DenBaars, Shuji Nakamura
  • (Al, In, Ga, B)N device structures on a patterned substrate
    Patent number: 8592802
    Abstract: A nitride light emitting diode, on a patterned substrate, comprising a nitride interlayer having at least two periods of alternating layers of InxGa1-xN and InyGa1-yN where 0<x<1 and 0?y<1, and a nitride based active region having at least one quantum well structure on the nitride interlayer.
    Type: Grant
    Filed: April 24, 2012
    Date of Patent: November 26, 2013
    Assignee: The Regents of the University of California
    Inventors: Michael Iza, Hitoshi Sato, Eu Jin Hwang, Steven P. DenBaars, Shuji Nakamura
  • HIGH OUTPUT POWER, HIGH EFFICIENCY BLUE LIGHT-EMITTING DIODES
    Publication number: 20130299776
    Abstract: A III-nitride based semipolar LED with a light output power of at least 100 milliwatts (mW), or with an External Quantum Efficiency (EQE) of at least 50%, for a current density of at least 100 Amps per centimeter square (A/cm2).
    Type: Application
    Filed: May 9, 2013
    Publication date: November 14, 2013
    Applicant: The Regents of the University of California
    Inventors: Shuji Nakamura, Steven P. DenBaars, Daniel F. Feezell, James S. Speck, Chih-Chien Pan, Shinichi Tanaka
  • LIGHT-EMITTING DIODES WITH LOW TEMPERATURE DEPENDENCE
    Publication number: 20130299777
    Abstract: A III-nitride based LED with an External Quantum Efficiency (EQE) droop of less than 10% when a junction temperature of the LED is increased from 20 ° C. to at least 100 ° C. at a current density of the LED of at least 20 Amps per centimeter square.
    Type: Application
    Filed: May 9, 2013
    Publication date: November 14, 2013
    Applicant: The Regents of the University of California
    Inventors: Shuji Nakamura, Steven P. DenBaars, Daniel F. Feezell, James S. Speck, Chih-Chien Pan