Patents by Inventor Robert M. Farrell

Robert M. Farrell 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: 20140211820
    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: March 28, 2014
    Publication date: July 31, 2014
    Applicants: Japan Science and Technology Agency, The Regents of the University of California
    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
  • 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
  • Patent number: 8588260
    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: Grant
    Filed: October 20, 2010
    Date of Patent: November 19, 2013
    Assignee: The Regents of the University of California
    Inventors: Robert M. Farrell, Mathew C. Schmidt, Kwang Choong Kim, Hisashi Masui, Daniel F. Feezell, James S. Speck, Stephen P. DenBaars, Shuji Nakamura
  • Publication number: 20120256158
    Abstract: A method for fabricating AlxGa1-xN-cladding-free nonpolar III-nitride based laser diodes or light emitting diodes. Due to the absence of polarization fields in the nonpolar crystal planes, these nonpolar devices have thick quantum wells that function as an optical waveguide to effectively confine the optical mode to the active region and eliminate the need for Al-containing waveguide cladding layers.
    Type: Application
    Filed: June 13, 2012
    Publication date: October 11, 2012
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Daniel F. Feezell, Mathew C. Schmidt, Kwang Choong Kim, Robert M. Farrell, Daniel A. Cohen, James S. Speck, Steven P. DenBaars, Shuji Nakamura
  • Publication number: 20120180868
    Abstract: A III-nitride photovoltaic device structure and method for fabricating the III-nitride photovoltaic device that increases the light collection efficiency of the III-nitride photovoltaic device. The III-nitride photovoltaic device includes one or more III-nitride device layers, and the III-nitride photovoltaic device functions by collecting light that is incident on the back-side of the III-nitride device layers. The III-nitride device layers are grown on a substrate, wherein the III-nitride device layers are exposed when the substrate is removed and the exposed III-nitride device layers are then intentionally roughened to enhance their light collection efficiency. The collection of the incident light via the back-side of the device simplifies the fabrication of the multiple junctions in the device. The III-nitride photovoltaic device may include grid-like contacts, transparent or semi-transparent contacts, or reflective contacts.
    Type: Application
    Filed: October 21, 2011
    Publication date: July 19, 2012
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Robert M. Farrell, Carl J. Neufeld, Nikholas G. Toledo, Steven P. DenBaars, Umesh K. Mishra, James S. Speck, Shuji Nakamura
  • Patent number: 8211723
    Abstract: A method for fabricating AlxGa1-xN-cladding-free nonpolar III-nitride based laser diodes or light emitting diodes. Due to the absence of polarization fields in the nonpolar crystal planes, these nonpolar devices have thick quantum wells that function as an optical waveguide to effectively confine the optical mode to the active region and eliminate the need for Al-containing waveguide cladding layers.
    Type: Grant
    Filed: February 12, 2008
    Date of Patent: July 3, 2012
    Assignee: The Regents of the University of California
    Inventors: Daniel F. Feezell, Mathew C. Schmidt, Kwang-Choong Kim, Robert M. Farrell, Daniel A. Cohen, James S. Speck, Steven P. DenBaars, Shuji Nakamura
  • Publication number: 20120104411
    Abstract: A method for fabricating a III-nitride semiconductor film, comprising depositing or growing a III-nitride semiconductor film in a semiconductor light absorbing or light emitting device structure; and growing a textured or structured surface of the III-nitride nitride semiconductor film in situ with the growing or the deposition of the III-nitride semiconductor film, by controlling the growing of the III-nitride semiconductor film to obtain a texture of the textured surface, or one or more structures of the structured surface, that increase output power of light from the light emitting device, or increase absorption of light in the light absorbing device.
    Type: Application
    Filed: October 27, 2011
    Publication date: May 3, 2012
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Michael Iza, Carl J. Neufeld, Samantha C. Cruz, Robert M. Farrell, James S. Speck, Shuji Nakamura, Steven P. DenBaars, Umesh K. Mishra
  • Publication number: 20110216795
    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: March 4, 2011
    Publication date: September 8, 2011
    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, S. James Speck
  • Publication number: 20110170569
    Abstract: A semipolar {20-21} III-nitride based laser diode employing a cavity with one or more etched facet mirrors. The etched facet mirrors provide an ability to arbitrarily control the orientation and dimensions of the cavity or stripe of the laser diode, thereby enabling control of electrical and optical properties of the laser diode.
    Type: Application
    Filed: October 20, 2010
    Publication date: July 14, 2011
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Anurag Tyagi, Robert M. Farrell, Chia-Yen Huang, Po Shan Hsu, Daniel A. Haeger, Kathryn M. Kelchner, Hiroaki Ohta, Shuji Nakamura, Steven P. DenBaars, James S. Speck
  • 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
  • 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
  • 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
  • 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
  • Patent number: 7846757
    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: June 1, 2006
    Date of Patent: December 7, 2010
    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 Kumar Mishra, Steven P. DenBaars, James S. Speck, Shuji Nakamura
  • Patent number: 7839903
    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: Grant
    Filed: February 12, 2008
    Date of Patent: November 23, 2010
    Assignees: 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
  • Publication number: 20100219416
    Abstract: A method for improving the growth morphology of (Ga,Al,In,B)N thin films on nonpolar or semipolar (Ga,Al,In,B)N substrates, wherein a (Ga,Al,In,B)N thin film is grown directly on a nonpolar or semipolar (Ga,Al,In,B)N substrate or template and a portion of the carrier gas used during growth is comprised of an inert gas. Nonpolar or semipolar nitride LEDs and diode lasers may be grown on the smooth (Ga,Al,In,B)N thin films grown by the present invention.
    Type: Application
    Filed: March 2, 2010
    Publication date: September 2, 2010
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Robert M. Farrell, Michael Iza, James S. Speck, Steven P. DenBaars, Shuji Nakamura
  • Patent number: 7480322
    Abstract: A vertical-cavity surface-emitting laser (VCSEL) comprising a low-loss thin metal contact and current spreading layer within the optical cavity that provides for improved ohmic contact and lateral current distribution, a substrate including a plano-concave optical cavity, a (Ga,In,Al)N multiple quantum well (MQW) active region contained within the optical cavity that generates light when injected by an electrical current, and an integrated micromirror fabricated onto the substrate that provides for optical mode control of the light generated by the active region. A relatively simple process is used to fabricate the VCSEL.
    Type: Grant
    Filed: May 15, 2007
    Date of Patent: January 20, 2009
    Assignee: The Regents of the University of California
    Inventors: Daniel F. Feezell, Daniel A. Cohen, Robert M. Farrell, Masahiro Ishida, Shuji Nakamura
  • Publication number: 20080198881
    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: February 12, 2008
    Publication date: August 21, 2008
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Robert M. Farrell, Mathew C. Schmidt, Kwang Choong Kim, Hisashi Masui, Daniel F. Feezell, James S. Speck, Steven P. DenBaars, Shuji Nakamura
  • Publication number: 20080191192
    Abstract: A method for fabricating AlxGa1-xN-cladding-free nonpolar III-nitride based laser diodes or light emitting diodes. Due to the absence of polarization fields in the nonpolar crystal planes, these nonpolar devices have thick quantum wells that function as an optical waveguide to effectively confine the optical mode to the active region and eliminate the need for Al-containing waveguide cladding layers.
    Type: Application
    Filed: February 12, 2008
    Publication date: August 14, 2008
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Daniel F. Feezell, Matthew C. Schmidt, Kwang Choong Kim, Robert M. Farrell, Daniel A. Cohen, James S. Speck, Steven P. DenBaars, Shuji Nakamura
  • Patent number: 6939088
    Abstract: A pneumatic transfer system having a modular pneumatic shifting device. A teller conduit has a teller station and a customer conduit has a customer station. A housing having apertures connected to the teller conduit and the customer conduit has a teller gate and a customer gate intermittently obstructing the apertures. A differential pressure generating mechanism is connected to the housing. A plurality of sensors send signals to a programmable means when a carrier pass through the system actuating movement of the gates and operation of the differential pressure generating mechanism.
    Type: Grant
    Filed: November 15, 2002
    Date of Patent: September 6, 2005
    Assignee: Protech Structural Industries
    Inventor: Robert M. Farrell