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).

  • Planar nonpolar m-plane group III nitride films grown on miscut substrates
    Patent number: 8158497
    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: June 16, 2008
    Date of Patent: April 17, 2012
    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
  • METHOD FOR INCREASING THE AREA OF NON-POLAR AND SEMI-POLAR NITRIDE SUBSTRATES
    Publication number: 20120086106
    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: Application
    Filed: December 15, 2011
    Publication date: April 12, 2012
    Applicant: The Regents of the University of California
    Inventors: Asako Hirai, James S. Speck, Steven P. DenBaars, Shuji Nakamura
  • Method for fabrication of semipolar (Al, In, Ga, B)N based light emitting diodes
    Patent number: 8148713
    Abstract: A yellow Light Emitting Diode (LED) with a peak emission wavelength in the range 560-580 nm is disclosed. The LED is grown on one or more III-nitride-based semipolar planes and an active layer of the LED is composed of indium (In) containing single or multi-quantum well structures. The LED quantum wells have a thickness in the range 2-7 nm. A multi-color LED or white LED comprised of at least one semipolar yellow LED is also disclosed.
    Type: Grant
    Filed: April 6, 2009
    Date of Patent: April 3, 2012
    Assignee: The Regents of the University of California
    Inventors: Hitoshi Sato, Hirohiko Hirasawa, Roy B. Chung, Steven P. DenBaars, James S. Speck, Shuji Nakamura
  • MISCUT SEMIPOLAR OPTOELECTRONIC DEVICE
    Publication number: 20120074525
    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: December 6, 2011
    Publication date: March 29, 2012
    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
  • ASYMMETRICALLY CLADDED LASER DIODE
    Publication number: 20120076165
    Abstract: A light emitting active region between a first cladding layer and a second cladding layer, wherein the first cladding layer has a lower refractive index than a refractive index of the second cladding layer, and the first cladding layer and the second cladding layer are III-nitride based.
    Type: Application
    Filed: June 7, 2010
    Publication date: March 29, 2012
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Arpan Chakraborty, You-Da Lin, Shuji Nakamura, Steven P. Denbaars
  • GROWTH OF REDUCED DISLOCATION DENSITY NON-POLAR GALLIUM NITRIDE
    Publication number: 20120074425
    Abstract: Lateral epitaxial overgrowth (LEO) of non-polar gallium nitride (GaN) films results in significantly reduced defect density.
    Type: Application
    Filed: December 1, 2011
    Publication date: March 29, 2012
    Applicants: JAPAN SCIENCE AND TECHNOLOGY AGENCY, THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Benjamin A. Haskell, Michael D. Craven, Paul T. Fini, Steven P. DenBaars, James S. Speck, Shuji Nakamura
  • GROWTH OF NON-POLAR M-PLANE III-NITRIDE FILM USING METALORGANIC CHEMICAL VAPOR DEPOSITION (MOCVD)
    Publication number: 20120074429
    Abstract: A method of growing non-polar m-plane III-nitride film, such as GaN, AlN, AlGaN or InGaN, wherein the non-polar m-plane III-nitride film is grown on a suitable substrate, such as an m-SiC, m-GaN, LiGaO2 or LiAlO2 substrate, using metalorganic chemical vapor deposition (MOCVD). The method includes performing a solvent clean and acid dip of the substrate to remove oxide from the surface, annealing the substrate, growing a nucleation layer, such as aluminum nitride (AlN), on the annealed substrate, and growing the non-polar m-plane III-nitride film on the nucleation layer using MOCVD.
    Type: Application
    Filed: December 7, 2011
    Publication date: March 29, 2012
    Applicants: JAPAN SCIENCE AND TECHNOLOGY AGENCY, THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Bilge M. Imer, James S. Speck, Steven P. DenBaars, Shuji Nakamura
  • DISLOCATION REDUCTION IN NON-POLAR III-NITRIDE THIN FILMS
    Publication number: 20120068184
    Abstract: Lateral epitaxial overgrowth of non-polar III-nitride seed layers reduces threading dislocations in the non-polar III-nitride thin films. First, a thin patterned dielectric mask is applied to the seed layer. Second, a selective epitaxial regrowth is performed to achieve a lateral overgrowth based on the patterned mask. Upon regrowth, the non-polar III-nitride films initially grow vertically through openings in the dielectric mask before laterally overgrowing the mask in directions perpendicular to the vertical growth direction. Threading dislocations are reduced in the overgrown regions by (1) the mask blocking the propagation of dislocations vertically into the growing film and (2) the bending of dislocations through the transition from vertical to lateral growth.
    Type: Application
    Filed: November 30, 2011
    Publication date: March 22, 2012
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Michael D. Craven, Steven P. DenBaars, James S. Speck, Shuji Nakamura
  • CRYSTAL GROWTH OF M-PLANE AND SEMIPOLAR PLANES OF (Al, In, Ga, B)N ON VARIOUS SUBSTRATES
    Publication number: 20120068192
    Abstract: A method of reducing threading dislocation densities in non-polar such as a-{11-20} plane and m-{1-100} plane or semi-polar such as {10-1n} plane III-Nitrides by employing lateral epitaxial overgrowth from sidewalls of etched template material through a patterned mask. The method includes depositing a patterned mask on a template material such as a non-polar or semi polar GaN template, etching the template material down to various depths through openings in the mask, and growing non-polar or semi-polar III-Nitride by coalescing laterally from the tops of the sidewalls before the vertically growing material from the trench bottoms reaches the tops of the sidewalls. The coalesced features grow through the openings of the mask, and grow laterally over the dielectric mask until a fully coalesced continuous film is achieved.
    Type: Application
    Filed: November 30, 2011
    Publication date: March 22, 2012
    Applicant: The Regents of the University of California
    Inventors: Kwang C. Kim, Mathew C. Schmidt, Feng Wu, Asako Hirai, Melvin B. McLaurin, Steven P. DenBaars, Shuji Nakamura, James S. Speck
  • OPTOELECTRONIC DEVICE BASED ON NON-POLAR AND SEMI-POLAR ALUMINUM INDIUM NITRIDE AND ALUMINUM INDIUM GALLIUM NITRIDE ALLOYS
    Publication number: 20120061645
    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: Application
    Filed: November 21, 2011
    Publication date: March 15, 2012
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Roy B. Chung, Zhen Chen, James S. Speck, Steven P. DenBaars, Shuji Nakamura
  • LIGHT EMITTING DIODES WITH A P-TYPE SURFACE BONDED TO A TRANSPARENT SUBMOUNT TO INCREASE LIGHT EXTRACTION EFFICIENCY
    Publication number: 20120056158
    Abstract: An (Al,Ga,In)N-based light emitting diode (LED), comprising a p-type surface of the LED bonded with a transparent submount material to increase light extraction at the p-type surface, wherein the LED is a substrateless membrane.
    Type: Application
    Filed: November 15, 2011
    Publication date: March 8, 2012
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Kenji Iso, Hirokuni Asamizu, Makoto Saito, Hitoshi Sato, Steven P. DenBaars, Shuji Nakamura
  • Technique for the growth of planar semi-polar gallium nitride
    Patent number: 8128756
    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) {10 11} gallium nitride (GaN) grown on a {100} spinel substrate miscut in specific directions, (2) {10 13 } gallium nitride (GaN) grown on a {110} spinel substrate, (3) {11 22} gallium nitride (GaN) grown on a {1 100} sapphire substrate, and (4) {10 13} gallium nitride (GaN) grown on a {1 100} sapphire substrate.
    Type: Grant
    Filed: February 1, 2010
    Date of Patent: March 6, 2012
    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
  • Light emitting diodes with a P-type surface bonded to a transparent submount to increase light extraction efficiency
    Patent number: 8124991
    Abstract: An (Al,Ga,In)N-based light emitting diode (LED), comprising a p-type surface of the LED bonded with a transparent submount material to increase light extraction at the p-type surface, wherein the LED is a substrateless membrane.
    Type: Grant
    Filed: July 28, 2008
    Date of Patent: February 28, 2012
    Assignee: The Regents of the University of California
    Inventors: Kenji Iso, Hirokuni Asamizu, Makoto Saito, Hitoshi Sato, Steven P. DenBaars, Shuji Nakamura
  • High light extraction efficiency nitride based light emitting diode by surface roughening
    Patent number: 8114698
    Abstract: A III-nitride light emitting diode (LED) and method of fabricating the same, wherein at least one surface of a semipolar or nonpolar plane of a III-nitride layer of the LED is textured, thereby forming a textured surface in order to increase light extraction. The texturing may be performed by plasma assisted chemical etching, photolithography followed by etching, or nano-imprinting followed by etching.
    Type: Grant
    Filed: December 1, 2008
    Date of Patent: February 14, 2012
    Assignee: The Regents of the University of California
    Inventors: Hong Zhong, Anurag Tyagi, Kenneth J. Vampola, James S. Speck, Steven P. DenBaars, Shuji Nakamura
  • Miscut semipolar optoelectronic device
    Patent number: 8110482
    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: Grant
    Filed: February 22, 2010
    Date of Patent: February 7, 2012
    Assignees: The Regents of the University of California, Japan Science and Technology Agency
    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
  • In-situ defect reduction techniques for nonpolar and semipolar (Al, Ga, In)N
    Patent number: 8105919
    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: April 14, 2010
    Date of Patent: January 31, 2012
    Assignee: The Regents of the University of California
    Inventors: Arpan Chakraborty, Kwang-Choong Kim, Steven P. DenBaars, James S. Speck, Umesh K. Mishra
  • Growth of non-polar M-plane III-nitride film using metalorganic chemical vapor deposition (MOCVD)
    Patent number: 8097481
    Abstract: A method of growing non-polar m-plane III-nitride film, such as GaN, AlN, AlGaN or InGaN, wherein the non-polar m-plane III-nitride film is grown on a suitable substrate, such as an m-SiC, m-GaN, LiGaO2 or LiAlO2 substrate, using metalorganic chemical vapor deposition (MOCVD). The method includes performing a solvent clean and acid dip of the substrate to remove oxide from the surface, annealing the substrate, growing a nucleation layer, such as aluminum nitride (AlN), on the annealed substrate, and growing the non-polar m-plane III-nitride film on the nucleation layer using MOCVD.
    Type: Grant
    Filed: October 10, 2007
    Date of Patent: January 17, 2012
    Assignees: The Regents of the University of California, Japan Science and Technology Agency
    Inventors: Bilge M. Imer, James S. Speck, Steven P. DenBaars, Shuji Nakamura
  • Optoelectronic device based on non-polar and semi-polar aluminum indium nitride and aluminum indium gallium nitride alloys
    Patent number: 8084763
    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: November 2, 2009
    Date of Patent: December 27, 2011
    Assignee: The Regents of the University of California
    Inventors: Roy B. Chung, Zhen Chen, James S. Speck, Steven P. DenBaars, Shuji Nakamura
  • Method for increasing the area of non-polar and semi-polar nitride substrates
    Patent number: 8080469
    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: September 19, 2008
    Date of Patent: December 20, 2011
    Assignee: The Regents of the University of California
    Inventors: Asako Hirai, James S. Speck, Steven P. DenBaars, Shuji Nakamura
  • GROUP-III NITRIDE MONOCRYSTAL WITH IMPROVED PURITY AND METHOD OF PRODUCING THE SAME
    Publication number: 20110300051
    Abstract: A method to improve the crystal purity of a group-I11 nitride crystal grown in an ammonothermal growth system by removing any undesired material (i.e., impurities) from within the system prior to, in-between, or after the growth steps for the group-I11 nitride crystal. Impurities are removed from the ammonothermal growth system by first bringing the impurities into solution and then removing part or all of the solution from the growth system. The result is a high purity group-I11 nitride crystal grown in the ammonothermal growth system.
    Type: Application
    Filed: November 4, 2009
    Publication date: December 8, 2011
    Applicant: The Regents of the University of California
    Inventors: Derrick S. Kamber, Siddha Pimputkar, Makoto Saito, Steven P. Denbaars, James S. Speck, Shuji Nakamura