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).
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Publication number: 20140211820Abstract: 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: ApplicationFiled: March 28, 2014Publication date: July 31, 2014Applicants: Japan Science and Technology Agency, The Regents of the University of CaliforniaInventors: 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
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Patent number: 8686466Abstract: 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: GrantFiled: November 23, 2010Date of Patent: April 1, 2014Assignees: The Regents of the University of California, Japan Science and Technology AgencyInventors: 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
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Patent number: 8588260Abstract: 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: GrantFiled: October 20, 2010Date of Patent: November 19, 2013Assignee: The Regents of the University of CaliforniaInventors: Robert M. Farrell, Mathew C. Schmidt, Kwang Choong Kim, Hisashi Masui, Daniel F. Feezell, James S. Speck, Stephen P. DenBaars, Shuji Nakamura
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Publication number: 20120256158Abstract: 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: ApplicationFiled: June 13, 2012Publication date: October 11, 2012Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIAInventors: Daniel F. Feezell, Mathew C. Schmidt, Kwang Choong Kim, Robert M. Farrell, Daniel A. Cohen, James S. Speck, Steven P. DenBaars, Shuji Nakamura
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Publication number: 20120180868Abstract: 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: ApplicationFiled: October 21, 2011Publication date: July 19, 2012Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIAInventors: Robert M. Farrell, Carl J. Neufeld, Nikholas G. Toledo, Steven P. DenBaars, Umesh K. Mishra, James S. Speck, Shuji Nakamura
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Patent number: 8211723Abstract: 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: GrantFiled: February 12, 2008Date of Patent: July 3, 2012Assignee: The Regents of the University of CaliforniaInventors: Daniel F. Feezell, Mathew C. Schmidt, Kwang-Choong Kim, Robert M. Farrell, Daniel A. Cohen, James S. Speck, Steven P. DenBaars, Shuji Nakamura
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Publication number: 20120104411Abstract: 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: ApplicationFiled: October 27, 2011Publication date: May 3, 2012Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIAInventors: Michael Iza, Carl J. Neufeld, Samantha C. Cruz, Robert M. Farrell, James S. Speck, Shuji Nakamura, Steven P. DenBaars, Umesh K. Mishra
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Publication number: 20110216795Abstract: 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: ApplicationFiled: March 4, 2011Publication date: September 8, 2011Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIAInventors: Po Shan Hsu, Kathryn M. Kelchner, Robert M. Farrell, Daniel A. Haeger, Hiroaki Ohta, Anurag Tyagi, Shuji Nakamura, Steven P. DenBaars, S. James Speck
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Publication number: 20110170569Abstract: 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: ApplicationFiled: October 20, 2010Publication date: July 14, 2011Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIAInventors: 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
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Publication number: 20110062449Abstract: 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: ApplicationFiled: November 23, 2010Publication date: March 17, 2011Applicants: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA, JAPAN SCIENCE AND TECHNOLOGY AGENCYInventors: 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
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Publication number: 20110044364Abstract: 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: ApplicationFiled: August 19, 2010Publication date: February 24, 2011Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIAInventors: Robert M. Farrell, Daniel A. Haeger, Po Shan Hsu, Umesh K. Mishra, Steven P. DenBaars, James S. Speck, Shuji Nakamura
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Publication number: 20110032965Abstract: 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: ApplicationFiled: October 20, 2010Publication date: February 10, 2011Applicants: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA, JAPAN SCIENCE AND TECHNOLOGY AGENCYInventors: Robert M. Farrell, Mathew C. Schmidt, Kwang Choong Kim, Hisashi Masui, Daniel F. Feezell, James S. Speck, Steven P. DenBaars, Shuji Nakamura
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Publication number: 20110007766Abstract: 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: ApplicationFiled: July 9, 2010Publication date: January 13, 2011Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIAInventors: Robert M. Farrell, Matthew T. Hardy, Hiroaki Ohta, Steven P. DenBaars, James S. Speck, Shuji Nakamura
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Patent number: 7846757Abstract: 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: GrantFiled: June 1, 2006Date of Patent: December 7, 2010Assignees: The Regents of the University of California, Japan Science and Technology AgencyInventors: 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
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Patent number: 7839903Abstract: 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: GrantFiled: February 12, 2008Date of Patent: November 23, 2010Assignees: The Regents of the University of California, Japan Science and Technology AgencyInventors: Robert M. Farrell, Mathew C. Schmidt, Kwang-Choong Kim, Hisashi Masui, Daniel F. Feezell, James S. Speck, Steven P. DenBaars, Shuji Nakamura
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Publication number: 20100219416Abstract: 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: ApplicationFiled: March 2, 2010Publication date: September 2, 2010Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIAInventors: Robert M. Farrell, Michael Iza, James S. Speck, Steven P. DenBaars, Shuji Nakamura
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Patent number: 7480322Abstract: 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: GrantFiled: May 15, 2007Date of Patent: January 20, 2009Assignee: The Regents of the University of CaliforniaInventors: Daniel F. Feezell, Daniel A. Cohen, Robert M. Farrell, Masahiro Ishida, Shuji Nakamura
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Publication number: 20080198881Abstract: 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: ApplicationFiled: February 12, 2008Publication date: August 21, 2008Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIAInventors: Robert M. Farrell, Mathew C. Schmidt, Kwang Choong Kim, Hisashi Masui, Daniel F. Feezell, James S. Speck, Steven P. DenBaars, Shuji Nakamura
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Publication number: 20080191192Abstract: 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: ApplicationFiled: February 12, 2008Publication date: August 14, 2008Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIAInventors: Daniel F. Feezell, Matthew C. Schmidt, Kwang Choong Kim, Robert M. Farrell, Daniel A. Cohen, James S. Speck, Steven P. DenBaars, Shuji Nakamura
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Patent number: 6939088Abstract: 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: GrantFiled: November 15, 2002Date of Patent: September 6, 2005Assignee: Protech Structural IndustriesInventor: Robert M. Farrell