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).

  • 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
  • FABRICATION OF NONPOLAR INDIUM GALLIUM NITRIDE THIN FILMS, HETEROSTRUCTURES, AND DEVICES BY METALORGANIC CHEMICAL VAPOR DEPOSITION
    Publication number: 20130264540
    Abstract: A method for the fabrication of nonpolar indium gallium nitride (InGaN) films as well as nonpolar InGaN-containing device structures using metalorganic chemical vapor deposition (MOVCD). The method is used to fabricate nonpolar InGaN/GaN violet and near-ultraviolet light emitting diodes and laser diodes.
    Type: Application
    Filed: June 4, 2013
    Publication date: October 10, 2013
    Applicants: JAPAN SCIENCE AND TECHNOLOGY AGENCY, THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Arpan Chakraborty, Benjamin A. Haskell, Stacia Keller, James S. Speck, Steven P. DenBaars, Shuji Nakamura, Umesh K. Mishra
  • ANISOTROPIC STRAIN CONTROL IN SEMIPOLAR NITRIDE QUANTUM WELLS BY PARTIALLY OR FULLY RELAXED ALUMINUM INDIUM GALLIUM NITRIDE LAYERS WITH MISFIT DISLOCATIONS
    Publication number: 20130259080
    Abstract: An epitaxial structure for a III-Nitride based optical device, comprising an active layer with anisotropic strain on an underlying layer, where a lattice constant and strain in the underlying layer are partially or fully relaxed in at least one direction due to a presence of misfit dislocations, so that the anisotropic strain in the active layer is modulated by the underlying layer.
    Type: Application
    Filed: May 29, 2013
    Publication date: October 3, 2013
    Inventors: Hiroaki Ohta, Feng Wu, Anurag Tyagi, Arpan Chakraborty, James S. Speck, Steven P. DenBaars, Shuji Nakamura, Erin C. Young
  • LED with current confinement structure and surface roughening
    Patent number: 8541788
    Abstract: A light emitting diode having a vertical orientation with an ohmic contact on portions of a top surface of the diode and a reflective layer adjacent the light emitting region of the diode. This light emitting diode includes a confinement structure. The confinement structure may be an opening in the reflective layer generally beneath the top ohmic contact that defines a non-contact area between the reflective layer and the light emitting region of the diode to encourage current flow to take place other than at the non-contact area to in turn decrease the number of light emitting recombinations beneath the ohmic contact and increase the number of light emitting recombinations in the areas not beneath said ohmic contact. The LED may include roughened emitting surfaces to further enhance light extraction.
    Type: Grant
    Filed: October 19, 2009
    Date of Patent: September 24, 2013
    Assignee: Cree, Inc.
    Inventors: Steven P. Denbaars, Shuji Nakamura, Max Batres
  • Cleaved facet (Ga,Al,In)N edge-emitting laser diodes grown on semipolar bulk gallium nitride substrates
    Patent number: 8541869
    Abstract: A III-nitride edge-emitting laser diode is formed on a surface of a III-nitride substrate having a semipolar orientation, wherein the III-nitride substrate is cleaved by creating a cleavage line along a direction substantially perpendicular to a nonpolar orientation of the III-nitride substrate, and then applying force along the cleavage line to create one or more cleaved facets of the III-nitride substrate, wherein the cleaved facets have an m-plane or a-plane orientation.
    Type: Grant
    Filed: February 12, 2008
    Date of Patent: September 24, 2013
    Assignee: The Regents of the University of California
    Inventors: Shuji Nakamura, James S. Speck, Steven P. DenBaars, Anurag Tyagi
  • 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
    Patent number: 8536618
    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: Grant
    Filed: November 3, 2010
    Date of Patent: September 17, 2013
    Assignee: The Regents of the University of California
    Inventors: Jacob J. Richardson, Daniel B. Thompson, Ingrid Koslow, Jun Seok Ha, Steven P. DenBaars, Shuji Nakamura, Maryann E. Lange
  • Solid solution phosphors based on oxyfluoride and white light emitting diodes including the phosphors for solid state white lighting applications
    Patent number: 8535565
    Abstract: Phosphor compositions comprising a solid solution series between Sr3AlO4F and Sr3SiO5 and a solid solution series between Sr3AlO4F and GdSr2AlO5, are disclosed. A white light emitting LED using the phosphor compositions is also disclosed.
    Type: Grant
    Filed: October 13, 2010
    Date of Patent: September 17, 2013
    Assignee: The Regents of the University of California
    Inventors: Won-Bin Im, Ram Seshadri, Steven P. DenBaars
  • Technique for the growth of planar semi-polar gallium nitride
    Patent number: 8524012
    Abstract: A method for growing planar, semi-polar nitride film on a miscut spinel substrate, in which a large area of the planar, semi-polar nitride film is parallel to the substrate's surface. The planar films and substrates are: (1) {1011} gallium nitride (GaN) grown on a {100} spinel substrate miscut in specific directions, (2) {1013} gallium nitride (GaN) grown on a {110} spinel substrate, (3) {1122} gallium nitride (GaN) grown on a {1100} sapphire substrate, and (4) {1013} gallium nitride (GaN) grown on a {1100} sapphire substrate.
    Type: Grant
    Filed: January 24, 2012
    Date of Patent: September 3, 2013
    Assignees: The Regents of the University of California, Japan Science and Technology Agency
    Inventors: Troy J. Baker, Benjamin A. Haskell, Paul T. Fini, Steven P. DenBaars, James S. Speck, Shuji Nakamua