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).

  • High efficiency light emitting diode (LED)
    Patent number: 7956371
    Abstract: An (Al, Ga, In)N light emitting diode (LED), wherein light extraction from chip and/or phosphor conversion layer is optimized. By novel shaping of LED and package optics, a high efficiency light emitting diode is achieved.
    Type: Grant
    Filed: December 8, 2006
    Date of Patent: June 7, 2011
    Assignee: The Regents of the University of California
    Inventors: Steven P. DenBaars, Shuji Nakamura, James S. Speck
  • 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: 20110108873
    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: November 3, 2010
    Publication date: May 12, 2011
    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
  • LIGHT EMITTING DEVICE WITH A COUPLED QUANTUM WELL STRUCTURE
    Publication number: 20110101301
    Abstract: A light emitting device with a coupled quantum well structure in an active region. The coupled quantum well structure may include two or more wells are separated by one or more mini-barriers, and the wells and mini-barriers together are sandwiched by barriers. The coupled quantum well structure provides almost the same effect as a wide quantum well, due to the coupling of the wavefunctions through the mini-barrier. The light emitting device may be a nonpolar, semipolar or polar (Al,Ga,In)N based light emitting device.
    Type: Application
    Filed: October 29, 2010
    Publication date: May 5, 2011
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: You-Da Lin, Arpan Chakraborty, Shuji Nakamura, Steven P. DenBaars
  • LIGHT EMITTING DIODE PACKAGING METHOD WITH HIGH LIGHT EXTRACTION AND HEAT DISSIPATION USING A TRANSPARENT VERTICAL STAND STRUCTURE
    Publication number: 20110103077
    Abstract: A packaging method for light emitting diodes provides both high light extraction and heat dissipation using a transparent vertical stand structure. A light emitting diode (LED) is attached to a vertical stand structure for supporting the LED, wherein the LED is bonded to the vertical stand structure, so that one of the LED's sides faces vertically upwards, another of the LED's sides faces vertically downwards, a top surface of the LED faces horizontally sideways in one direction, and a bottom surface of the LED faces horizontally sideways in another direction. The vertical stand structure comprises a connecting stem between the LED and a header, and is made of a material that provides for heat dissipation and may also be transparent to light generated in the LED, such as sapphire or zinc oxide. The LED and the vertical stand structure may be encapsulated within a mold.
    Type: Application
    Filed: October 20, 2010
    Publication date: May 5, 2011
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Chih-Chien Pan, Jun Seok Ha, Steven P. DenBaars, Shuji Nakamura, Junichi Sonoda
  • LIGHT EMITTING DIODES WITH ZINC OXIDE CURRENT SPREADING AND LIGHT EXTRACTION LAYERS DEPOSITED FROM LOW TEMPERATURE AQUEOUS SOLUTION
    Publication number: 20110101414
    Abstract: A method for fabricating a Light Emitting Diode (LED) with increased light extraction efficiency, comprising providing a III-Nitride based LED structure comprising a light emitting active layer between a p-type layer and an n-type layer; growing a Zinc Oxide (ZnO) layer epitaxially on the p-type layer by submerging a surface of the p-type layer in a low temperature aqueous solution, wherein the ZnO layer is a transparent current spreading layer; and depositing a p-type contact on the ZnO layer. The increase in efficiency may be more than 93% with very little or no increase in cost.
    Type: Application
    Filed: November 3, 2010
    Publication date: May 5, 2011
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Daniel B. Thompson, Jacob J. Richardson, Steven P. DenBaars, Frederick F. Lange, MaryAnn E. Lange, Jin Hyeok Kim
  • SUPERLUMINESCENT DIODES BY CRYSTALLOGRAPHIC ETCHING
    Publication number: 20110103418
    Abstract: An optoelectronic device, comprising an active region and a waveguide structure to provide optical confinement of light emitted from the active region; a pair of facets on opposite ends of the device, having opposite surface polarity; and one of the facets which has been roughened by a crystallographic chemical etching process, wherein the device is a nonpolar or semipolar (Ga,In,Al,B)N based device.
    Type: Application
    Filed: October 27, 2010
    Publication date: May 5, 2011
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Matthew T. Hardy, You-Da Lin, Hiroaki Ohta, Steven P. DenBaars, James S. Speck, Shuji Nakamura, Kathryn M. Kelchner
  • SOLID SOLUTION PHOSPHORS BASED ON OXYFLUORIDE AND WHITE LIGHT EMITTING DIODES INCLUDING THE PHOSPHORS FOR SOLID STATE WHITE LIGHTING APPLICATIONS
    Publication number: 20110101272
    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: Application
    Filed: October 13, 2010
    Publication date: May 5, 2011
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Won-Bin Im, Ram Seshadri, Steven P. DenBaars
  • OPTICAL DESIGNS FOR HIGH-EFFICACY WHITE-LIGHT EMITTING DIODES
    Publication number: 20110089455
    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 21, 2010
    Publication date: April 21, 2011
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Frederic S. Diana, Steven P. DenBaars, Shuji Nakamura
  • LIGHT EMITTING DEVICE WITH A STAIR QUANTUM WELL STRUCTURE
    Publication number: 20110089399
    Abstract: A light emitting device with a stair quantum well structure in an active region. The stair quantum well structure may include a primary well and a single step or multiple steps. The light emitting device may be a nonpolar, semipolar or polar (Al,Ga,In)N based light emitting device. The stair quantum structure improves the radiative efficiency of the light emitting device.
    Type: Application
    Filed: October 11, 2010
    Publication date: April 21, 2011
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Arpan Chakraborty, You-Da Lin, Shuji Nakamura, Steven P. DenBaars
  • TECHNIQUE FOR THE GROWTH AND FABRICATION OF SEMIPOLAR (GA,AL,IN,B)N THIN FILMS, HETEROSTRUCTURES, AND DEVICES
    Publication number: 20110062449
    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: Application
    Filed: November 23, 2010
    Publication date: March 17, 2011
    Applicants: 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 Kumar Mishra, Steven P. DenBaars, James S. Speck, Shuji Nakamura
  • SEMIPOLAR NITRIDE-BASED DEVICES ON PARTIALLY OR FULLY RELAXED ALLOYS WITH MISFIT DISLOCATIONS AT THE HETEROINTERFACE
    Publication number: 20110064103
    Abstract: A dislocation-free high quality template with relaxed lattice constant, fabricated by spatially restricting misfit dislocation(s) around heterointerfaces. This can be used as a template layer for high In composition devices. Specifically, the present invention prepares high quality InGaN templates (In composition is around 5-10%), and can grow much higher In-composition InGaN quantum wells (QWs) (or multi quantum wells (MQWs)) on these templates than would otherwise be possible.
    Type: Application
    Filed: August 23, 2010
    Publication date: March 17, 2011
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Hiroaki Ohta, Feng Wu, Anurag Tyagi, Arpan Chakraborty, James S. Speck, Steven P. DenBaars, Shuji Nakamura, Erin C. Young
  • ANISOTROPIC STRAIN CONTROL IN SEMIPOLAR NITRIDE QUANTUM WELLS BY PARTIALLY OR FULLY RELAXED ALUMINUM INDIUM GALLIUM NITRIDE LAYERS WITH MISFIT DISLOCATIONS
    Publication number: 20110062415
    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: August 23, 2010
    Publication date: March 17, 2011
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Hiroaki Ohta, Feng Wu, Anurag Tyagi, Arpan Chakraborty, James S. Speck, Steven P. DenBaars, Shuji Nakamura, Erin C. Young
  • STRUCTURE AND METHOD FOR ACHIEVING SELECTIVE ETCHING IN (Ga,Al,In,B)N LASER DIODES
    Publication number: 20110044364
    Abstract: A structure and method that can be used to achieve selective etching in (Ga, Al, In, B) N laser diodes, comprising fabricating (Ga, Al, In, B) N laser diodes with one or more Al-containing etch stop layers.
    Type: Application
    Filed: August 19, 2010
    Publication date: February 24, 2011
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Robert M. Farrell, Daniel A. Haeger, Po Shan Hsu, Umesh K. Mishra, Steven P. DenBaars, James S. Speck, Shuji Nakamura
  • THIN P-TYPE GALLIUM NITRIDE AND ALUMINUM GALLIUM NITRIDE ELECTRON-BLOCKING LAYER FREE GALLIUM NITRIDE-BASED LIGHT EMITTING DIODES
    Publication number: 20110037085
    Abstract: A light emitting diode (LED) having a p-type layer having a thickness of 100 nm or less, an n-type layer, and an active layer, positioned between the p-type layer and the n-type layer, for emitting light, wherein the LED does not include a separate electron blocking layer.
    Type: Application
    Filed: November 2, 2009
    Publication date: February 17, 2011
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Hong Zhong, Anurag Tyagi, James S. Speck, Steven P. DenBaars, Shuji Nakamura
  • METALORGANIC CHEMICAL VAPOR DEPOSITION (MOCVD) GROWTH OF HIGH PERFORMANCE NON-POLAR III-NITRIDE OPTICAL DEVICES
    Publication number: 20110037052
    Abstract: A method of device growth and p-contact processing that produces improved performance for non-polar III-nitride light emitting diodes and laser diodes. Key components using a low defect density substrate or template, thick quantum wells, a low temperature p-type III-nitride growth technique, and a transparent conducting oxide for the electrodes.
    Type: Application
    Filed: October 28, 2010
    Publication date: February 17, 2011
    Applicants: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA, JAPAN SCIENCE AND TECHNOLOGY AGENCY
    Inventors: Mathew C. Schmidt, Kwang Choong Kim, Hitsohi Sato, Steven P. DenBaars, James S. Speck, Shuji Nakamura
  • OPTIMIZATION OF LASER BAR ORIENTATION FOR NONPOLAR AND SEMIPOLAR (Ga,Al,In,B)N DIODE LASERS
    Publication number: 20110032965
    Abstract: Optical gain of a nonpolar or semipolar Group-III nitride diode laser is controlled by orienting an axis of light propagation in relation to an optical polarization direction or crystallographic orientation of the diode laser. The axis of light propagation is substantially perpendicular to the mirror facets of the diode laser, and the optical polarization direction is determined by the crystallographic orientation of the diode laser. To maximize optical gain, the axis of light propagation is oriented substantially perpendicular to the optical polarization direction or crystallographic orientation.
    Type: Application
    Filed: October 20, 2010
    Publication date: February 10, 2011
    Applicants: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA, JAPAN SCIENCE AND TECHNOLOGY AGENCY
    Inventors: Robert M. Farrell, Mathew C. Schmidt, Kwang Choong Kim, Hisashi Masui, Daniel F. Feezell, James S. Speck, Steven P. DenBaars, Shuji Nakamura
  • METHOD FOR GROWTH OF SEMIPOLAR (AL,IN,GA,B)N OPTOELECTRONIC DEVICES
    Publication number: 20110012234
    Abstract: A method of fabricating an optoelectronic device, comprising growing an active layer of the device on an oblique surface of a suitable material, wherein the oblique surface comprises a facetted surface. The present invention also discloses a method of fabricating the facetted surfaces. One fabrication process comprises growing an epitaxial layer on a suitable material, etching the epitaxial layer through a mask to form the facets having a specific crystal orientation, and depositing one or more active layers on the facets. Another method comprises growing a layer of material using a lateral overgrowth technique to produce a facetted surface, and depositing one or more active layers on the facetted surfaces. The facetted surfaces are typically semipolar planes.
    Type: Application
    Filed: September 24, 2010
    Publication date: January 20, 2011
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Hong Zhong, John F. Kaeding, Rajat Sharma, James S. Speck, Steven P. DenBaars, Shuji Nakamua
  • STRUCTURE FOR IMPROVING THE MIRROR FACET CLEAVING YIELD OF (Ga,Al,In,B)N LASER DIODES GROWN ON NONPOLAR OR SEMIPOLAR (Ga,Al,In,B)N SUBSTRATES
    Publication number: 20110007766
    Abstract: A structure for improving the mirror facet cleaving yield of (Ga,Al,In,B)N laser diodes grown on nonpolar or semipolar (Ga,Al,In,B)N substrates. The structure comprises a nonpolar or semipolar (Ga,Al,In,B)N laser diode including a waveguide core that provides sufficient optical confinement for the device's operation in the absence of p-type doped aluminum-containing waveguide cladding layers, and one of more n-type doped aluminum-containing layers that can be used to assist with facet cleaving along a particular crystallographic plane.
    Type: Application
    Filed: July 9, 2010
    Publication date: January 13, 2011
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Robert M. Farrell, Matthew T. Hardy, Hiroaki Ohta, Steven P. DenBaars, James S. Speck, Shuji Nakamura
  • Optical designs for high-efficacy white-light emitting diodes
    Patent number: 7868341
    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: June 27, 2008
    Date of Patent: January 11, 2011
    Assignee: The Regents of the University of California
    Inventors: Frederic S. Diana, Steven P. DenBaars, Shuji Nakamura
  • Method for growth of semipolar (Al,In,Ga,B)N optoelectronic devices
    Patent number: 7858996
    Abstract: A method of fabricating an optoelectronic device, comprising growing an active layer of the device on an oblique surface of a suitable material, wherein the oblique surface comprises a facetted surface. The present invention also discloses a method of fabricating the facetted surfaces. One fabrication process comprises growing an epitaxial layer on a suitable material, etching the epitaxial layer through a mask to form the facets having a specific crystal orientation, and depositing one or more active layers on the facets. Another method comprises growing a layer of material using a lateral overgrowth technique to produce a facetted surface, and depositing one or more active layers on the facetted surfaces. The facetted surfaces are typically semipolar planes.
    Type: Grant
    Filed: February 20, 2007
    Date of Patent: December 28, 2010
    Assignee: The Regents of the University of California
    Inventors: Hong Zhong, John F. Kaeding, Rajat Sharma, James S. Speck, Steven P. DenBaars, Shuji Nakamura