Patents by Inventor James S. Speck

James S. Speck 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).

  • Publication number: 20160345398
    Abstract: Disclosed is an improved light-emitting device for an AC power operation. A conventional light emitting device employs an AC light-emitting diode having arrays of light emitting cells connected in reverse parallel. The arrays in the prior art alternately repeat on/off in response to a phase change of an AC power source, resulting in short light emission time during a ½ cycle and the occurrence of a flicker effect. An AC light-emitting device according to the present invention employs a variety of means by which light emission time is prolonged during a ½ cycle in response to a phase change of an AC power source and a flicker effect can be reduced. For example, the means may be switching blocks respectively connected to nodes between the light emitting cells, switching blocks connected to a plurality of arrays, or a delay phosphor.
    Type: Application
    Filed: August 5, 2016
    Publication date: November 24, 2016
    Inventors: Chung Hoon Lee, James S. Speck, Hong San Kim, Jae Jo Kim, Sung Han Kim, Jae Ho Lee
  • Patent number: 9445462
    Abstract: Disclosed is an improved light-emitting device for an AC power operation. A conventional light emitting device employs an AC light-emitting diode having arrays of light emitting cells connected in reverse parallel. The arrays in the prior art alternately repeat on/off in response to a phase change of an AC power source, resulting in short light emission time during a ½ cycle and the occurrence of a flicker effect. An AC light-emitting device according to the present invention employs a variety of means by which light emission time is prolonged daring a ½ cycle in response to a phase change of an AC power source and a flicker effect can be reduced. For example, the means may be switching blocks respectively connected to nodes between the light emitting cells, switching blocks connected to a plurality of arrays, or a delay phosphor.
    Type: Grant
    Filed: March 20, 2015
    Date of Patent: September 13, 2016
    Assignee: SEOUL VIOSYS CO., LTD.
    Inventors: Chung Hoon Lee, James S. Speck, Hong San Kim, Jae Jo Kim, Sung Han Kim, Jae Ho Lee
  • Publication number: 20160230312
    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: Application
    Filed: April 20, 2016
    Publication date: August 11, 2016
    Applicant: 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
  • Publication number: 20160194781
    Abstract: A method and apparatus for growing a Group-III nitride crystal using multiple interconnected reactor vessels to modify growth conditions during the ammonothermal growth of the Group-III nitride crystal, such that, by combining two or more vessels, it is possible to modify the conditions under which the Group-III nitride crystals are grown. In addition, the reactor vessel may use carbon fiber containing materials encapsulating oxide ceramic materials as structural elements to contain the materials for growing the Group-III nitride crystals at pressures or temperatures necessary for growth of the Group-III nitride crystals.
    Type: Application
    Filed: August 29, 2014
    Publication date: July 7, 2016
    Applicant: The Regents of the University of California
    Inventors: Siddha Pimputkar, Shuji Nakamura, James S. Speck
  • Publication number: 20160156155
    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: August 6, 2015
    Publication date: June 2, 2016
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Casey O. Holder, Daniel F. Feezell, Steven P. DenBaars, James S. Speck, Shuji Nakamura
  • Patent number: 9356431
    Abstract: A high power blue-violet Ill-nitride semipolar laser diode (LD) with an output power in excess of 1 W, a slope efficiency of more than 1 W/A, and an external quantum efficiency (EQE) in excess of 25% and more preferably, in excess of 35%. These operating characteristics make these laser diodes suitable for use in solid state lighting systems.
    Type: Grant
    Filed: February 13, 2014
    Date of Patent: May 31, 2016
    Assignee: The Regents of the University of California
    Inventors: Arash Pourhashemi, Robert M. Farrell, Steven P. DenBaars, James S. Speck, Shuji Nakamura
  • Patent number: 9340899
    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, 2014
    Date of Patent: May 17, 2016
    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
  • Publication number: 20160079738
    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 30, 2015
    Publication date: March 17, 2016
    Applicants: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA, Japan Science and Technology Agency
    Inventors: Robert M. Farrell, Troy J. Baker, Arpan Chakraborty, Benjamin A. Haskell, P. Morgan Pattison, Rajat Sharma, Umesh K. Mishra, Steven P. DenBaars, James S. Speck, Shuji Nakamura
  • Publication number: 20160053400
    Abstract: A large area nitride crystal, comprising gallium and nitrogen, with a non-polar or semi-polar large-area face, is disclosed, along with a method of manufacture. The crystal is useful as a substrate for a light emitting diode, a laser diode, a transistor, a photodetector, a solar cell, or for photoelectrochemical water splitting for hydrogen generation.
    Type: Application
    Filed: November 2, 2015
    Publication date: February 25, 2016
    Inventors: MARK P. D'EVELYN, JAMES S. SPECK
  • Patent number: 9231376
    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: March 28, 2014
    Date of Patent: January 5, 2016
    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
  • Publication number: 20150372456
    Abstract: A high power blue-violet Ill-nitride semi-polar laser diode (LD) with an output power in excess of 1 W, a slope efficiency of more than 1 W/A, and an external quantum efficiency (EQE) in excess of 25% and more preferably, in excess of 35%. These operating characteristics make these laser diodes suitable for use in solid state lighting systems.
    Type: Application
    Filed: February 13, 2014
    Publication date: December 24, 2015
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Arash Pourhashemi, Robert M. Farrell, Steven P. DenBaars, James S. Speck, Shuji Nakamura
  • Patent number: 9175418
    Abstract: A large area nitride crystal, comprising gallium and nitrogen, with a non-polar or semi-polar large-area face, is disclosed, along with a method of manufacture. The crystal is useful as a substrate for a light emitting diode, a laser diode, a transistor, a photodetector, a solar cell, or for photoelectrochemical water splitting for hydrogen generation.
    Type: Grant
    Filed: October 11, 2010
    Date of Patent: November 3, 2015
    Assignee: Soraa, Inc.
    Inventors: Mark P. D'Evelyn, James S. Speck
  • Patent number: 9159553
    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: Grant
    Filed: August 23, 2010
    Date of Patent: October 13, 2015
    Assignee: 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
  • Patent number: 9136673
    Abstract: A III-Nitride based Vertical Cavity Surface Emitting Laser (VCSEL), wherein a cavity length of the VCSEL is controlled by etching.
    Type: Grant
    Filed: July 22, 2013
    Date of Patent: September 15, 2015
    Assignee: The Regents of the University of California
    Inventors: Casey O. Holder, Daniel F. Feezell, Steven P. DenBaars, James S. Speck, Shuji Nakamura
  • Patent number: 9133564
    Abstract: An ammonothermal growth of group-III nitride crystals on starting seed crystals with at least two surfaces making an acute, right or obtuse angle, i.e., greater than 0 degrees and less than 180 degrees, with respect to each other, such that the exposed surfaces together form a concave surface.
    Type: Grant
    Filed: October 28, 2011
    Date of Patent: September 15, 2015
    Assignee: The Regents of the University of California
    Inventors: Siddha Pimputkar, James S. Speck, Shuji Nakamura, Shin-Ichiro Kawabata
  • Publication number: 20150255959
    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: Application
    Filed: May 26, 2015
    Publication date: September 10, 2015
    Applicant: 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: 9130119
    Abstract: An (Al, Ga, In)N light emitting device, such as a light emitting diode (LED), in which high light generation efficiency is realized by fabricating the device on non-polar or semi-polar III-Nitride crystal geometries. Because non-polar and semi-polar emitting devices have significantly lower piezoelectric effects than c-plane emitting devices, higher efficiency emitting devices at higher current densities can be realized.
    Type: Grant
    Filed: December 11, 2007
    Date of Patent: September 8, 2015
    Assignees: The Regents of the University of California, Japan Science and Technology Agency
    Inventors: Steven P. DenBaars, Mathew C. Schmidt, Kwang Choong Kim, James S. Speck, Shuji Nakamura
  • Patent number: 9129977
    Abstract: Methods of controlling stress in GaN films deposited on silicon and silicon carbide substrates and the films produced therefrom are disclosed. A typical method comprises providing a substrate and depositing a graded gallium nitride layer on the substrate having a varying composition of a substantially continuous grade from an initial composition to a final composition formed from a supply of at least one precursor in a growth chamber without any interruption in the supply. A typical semiconductor film comprises a substrate and a graded gallium nitride layer deposited on the substrate having a varying composition of a substantially continuous grade from an initial composition to a final composition formed from a supply of at least one precursor in a growth chamber without any interruption in the supply.
    Type: Grant
    Filed: November 29, 2011
    Date of Patent: September 8, 2015
    Assignee: The Regents of the University of California
    Inventors: Hugues Marchand, Brendan J. Moran, Umesh K. Mishra, James S. Speck
  • Publication number: 20150195872
    Abstract: Disclosed is an improved light-emitting device for an AC power operation. A conventional light emitting device employs an AC light-emitting diode having arrays of light emitting cells connected in reverse parallel. The arrays in the prior art alternately repeat on/off in response to a phase change of an AC power source, resulting in short light emission time during a ½ cycle and the occurrence of a flicker effect. An AC light-emitting device according to the present invention employs a variety of means by which light emission time is prolonged daring a ½ cycle in response to a phase change of an AC power source and a flicker effect can be reduced. For example, the means may be switching blocks respectively connected to nodes between the light emitting cells, switching blocks connected to a plurality of arrays, or a delay phosphor.
    Type: Application
    Filed: March 20, 2015
    Publication date: July 9, 2015
    Inventors: Chung Hoon Lee, James S. Speck, Hong San Kim, Jae Jo Kim, Sung Han Kim, Jae Ho Lee
  • Patent number: 9040326
    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: August 11, 2014
    Date of Patent: May 26, 2015
    Assignee: The Regents of the University of California
    Inventors: Hong Zhong, Anurag Tyagi, Kenneth J. Vampola, James S. Speck, Steven P. DenBaars, Shuji Nakamura