Patents by Inventor David Todd Emerson

David Todd Emerson 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).

  • Patent number: 7613219
    Abstract: Methods of forming a semiconductor device can include forming a semiconductor structure on a substrate, the semiconductor structure having mesa sidewalls and a mesa surface opposite the substrate. A contact layer can be formed on the mesa surface wherein the contact layer has sidewalls and a contact surface opposite the mesa surface and wherein the contact layer extends across substantially an entirety of the mesa surface. A passivation layer can be formed on the mesa sidewalls and on portions of the contact layer sidewalls adjacent the mesa surface, and the passivation layer can expose substantially an entirety of the contact surface of the contact layer. Related devices are also discussed.
    Type: Grant
    Filed: September 13, 2006
    Date of Patent: November 3, 2009
    Assignee: Cree, Inc.
    Inventors: Kevin Ward Haberern, Raymond Rosado, Michael John Bergman, David Todd Emerson
  • Patent number: 7611917
    Abstract: Light emitting devices include an active region comprising a plurality of layers and a pit opening region on which the active region is disposed. The pit opening region is configured to expand a size of openings of a plurality of pits to a size sufficient for the plurality of layers of the active region to extend into the pits. In some embodiments, the active region comprises a plurality of quantum wells. The pit opening region may comprise a superlattice structure. The pits may surround their corresponding dislocations and the plurality of layers may extend to the respective dislocations. At least one of the pits of the plurality of pits may originate in a layer disposed between the pit opening layer and a substrate on which the pit opening layer is provided. The active region may be a Group III nitride based active region. Methods of fabricating such devices are also provided.
    Type: Grant
    Filed: October 1, 2008
    Date of Patent: November 3, 2009
    Assignee: Cree, Inc.
    Inventors: David Todd Emerson, Michael John Bergmann
  • Publication number: 20090261358
    Abstract: A method for fabricating light emitting diode (LED) chips comprising providing a plurality of LEDs, typically on a wafer, and coating the LEDs with a conversion material so that at least some light from the LEDs passes through the conversion material and is converted. The light emission from the LED chips comprises light from the conversion material, typically in combination with LED light. The emission characteristics of at least some of the LED chips is measured and at least some of the conversion material over the LEDs is removed to alter the emission characteristics of the LED chips. The invention is particularly applicable to fabricating LED chips on a wafer where the LED chips have light emission characteristics that are within a range of target emission characteristics. This target range can fall within an emission region on a CIE curve to reduce the need for binning of the LEDs from the wafer.
    Type: Application
    Filed: March 30, 2009
    Publication date: October 22, 2009
    Inventors: ASHAY CHITNIS, JOHN EDMOND, JEFFREY CARL BRITT, BERND P. KELLER, DAVID TODD EMERSON, MICHAEL JOHN BERGMANN, JASPER S. CABALU
  • Publication number: 20090250716
    Abstract: Light emitting devices include an active region of semiconductor material and a first contact on the active region. The first contact is configured such that photons emitted by the active region pass through the first contact. A photon absorbing wire bond pad is provided on the first contact. The wire bond pad has an area less than the area of the first contact. A reflective structure is disposed between the first contact and the wire bond pad such that the reflective structure has substantially the same area as the wire bond pad. A second contact is provided opposite the active region from the first contact. The reflective structure may be disposed only between the first contact and the wire bond pad. Methods of fabricating such devices are also provided.
    Type: Application
    Filed: June 2, 2009
    Publication date: October 8, 2009
    Inventors: Kevin Haberern, Michael John Bergmann, Van Mieczkowski, David Todd Emerson
  • Publication number: 20090242897
    Abstract: Light emitting devices include a gallium nitride-based epitaxial structure that includes an active light emitting region and a gallium nitride-based outer layer, for example gallium nitride. A indium nitride-based layer, such as indium gallium nitride, is provided directly on the outer layer. A reflective metal layer or a transparent conductive oxide layer is provided directly on the indium gallium nitride layer opposite the outer layer. The indium gallium nitride layer forms a direct ohmic contact with the outer layer. An ohmic metal layer need not be used. Related fabrication methods are also disclosed.
    Type: Application
    Filed: June 24, 2008
    Publication date: October 1, 2009
    Inventors: Michael John Bergmann, Daniel Carleton Driscoll, David Todd Emerson
  • Patent number: 7557379
    Abstract: Light emitting devices include an active region of semiconductor material and a first contact on the active region. The first contact is configured such that photons emitted by the active region pass through the first contact. A photon absorbing wire bond pad is provided on the first contact. The wire bond pad has an area less than the area of the first contact. A reflective structure is disposed between the first contact and the wire bond pad such that the reflective structure has substantially the same area as the wire bond pad. A second contact is provided opposite the active region from the first contact. The reflective structure may be disposed only between the first contact and the wire bond pad. Methods of fabricating such devices are also provided.
    Type: Grant
    Filed: May 19, 2008
    Date of Patent: July 7, 2009
    Assignee: Cree, Inc.
    Inventors: Kevin Haberern, Michael John Bergmann, Van Mieczkowski, David Todd Emerson
  • Patent number: 7557380
    Abstract: Light emitting devices include an active region of semiconductor material and a first contact on the active region. The first contact is configured such that photons emitted by the active region pass through the first contact. A photon absorbing wire bond pad is provided on the first contact. The wire bond pad has an area less than the area of the first contact. A reflective structure is disposed between the first contact and the wire bond pad such that the reflective structure has substantially the same area as the wire bond pad. A second contact is provided opposite the active region from the first contact. The reflective structure may be disposed only between the first contact and the wire bond pad. Methods of fabricating such devices are also provided.
    Type: Grant
    Filed: July 27, 2004
    Date of Patent: July 7, 2009
    Assignee: Cree, Inc.
    Inventors: Kevin Haberern, Michael John Bergmann, Van Mieczkowski, David Todd Emerson
  • Publication number: 20090029493
    Abstract: Light emitting devices include an active region comprising a plurality of layers and a pit opening region on which the active region is disposed. The pit opening region is configured to expand a size of openings of a plurality of pits to a size sufficient for the plurality of layers of the active region to extend into the pits. In some embodiments, the active region comprises a plurality of quantum wells. The pit opening region may comprise a superlattice structure. The pits may surround their corresponding dislocations and the plurality of layers may extend to the respective dislocations. At least one of the pits of the plurality of pits may originate in a layer disposed between the pit opening layer and a substrate on which the pit opening layer is provided. The active region may be a Group III nitride based active region. Methods of fabricating such devices are also provided.
    Type: Application
    Filed: October 1, 2008
    Publication date: January 29, 2009
    Inventors: David Todd Emerson, Michael John Bergmann
  • Patent number: 7446345
    Abstract: Light emitting devices include an active region comprising a plurality of layers and a pit opening region on which the active region is disposed. The pit opening region is configured to expand a size of openings of a plurality of pits to a size sufficient for the plurality of layers of the active region to extend into the pits. In some embodiments, the active region comprises a plurality of quantum wells. The pit opening region may comprise a superlattice structure. The pits may surround their corresponding dislocations and the plurality of layers may extend to the respective dislocations. At least one of the pits of the plurality of pits may originate in a layer disposed between the pit opening layer and a substrate on which the pit opening layer is provided. The active region may be a Group III nitride based active region. Methods of fabricating such devices are also provided.
    Type: Grant
    Filed: April 29, 2005
    Date of Patent: November 4, 2008
    Assignee: Cree, Inc.
    Inventors: David Todd Emerson, Michael John Bergmann
  • Publication number: 20080217635
    Abstract: A light emitting device includes a p-type semiconductor layer, an n-type semiconductor layer, and an active region between the n-type semiconductor layer and the p-type semiconductor layer. A non-transparent feature, such as a wire bond pad, is on the p-type semiconductor layer or on the n-type semiconductor layer opposite the p-type semiconductor layer, and a reduced conductivity region is in the p-type semiconductor layer or the n-type semiconductor layer and is aligned with the non-transparent feature. The reduced conductivity region may extend from a surface of the p-type semiconductor layer opposite the n-type semiconductor layer towards the active region and/or from a surface of the n-type semiconductor layer opposite the p-type semiconductor layer towards the active region.
    Type: Application
    Filed: March 8, 2007
    Publication date: September 11, 2008
    Inventors: David Todd Emerson, Kevin Haberern, Michael John Bergmann, David B. Slater, Matthew Donofrio, John Edmond
  • Publication number: 20080217641
    Abstract: Light emitting devices include an active region of semiconductor material and a first contact on the active region. The first contact is configured such that photons emitted by the active region pass through the first contact. A photon absorbing wire bond pad is provided on the first contact. The wire bond pad has an area less than the area of the first contact. A reflective structure is disposed between the first contact and the wire bond pad such that the reflective structure has substantially the same area as the wire bond pad. A second contact is provided opposite the active region from the first contact. The reflective structure may be disposed only between the first contact and the wire bond pad. Methods of fabricating such devices are also provided.
    Type: Application
    Filed: May 19, 2008
    Publication date: September 11, 2008
    Inventors: Kevin Haberern, Michael John Bergmann, Van Mieczkowski, David Todd Emerson
  • Publication number: 20080142783
    Abstract: Light emitting devices and methods of fabricating light emitting devices that emit at wavelengths less than 360 nm with wall plug efficiencies of at least than 4% are provided. Wall plug efficiencies may be at least 5% or at least 6%. Light emitting devices and methods of fabricating light emitting devices that emit at wavelengths less than 345 nm with wall plug efficiencies of at least than 2% are also provided. Light emitting devices and methods of fabricating light emitting devices that emit at wavelengths less than 330 nm with wall plug efficiencies of at least than 0.4% are provided. Light emitting devices and methods of fabricating light emitting devices having a peak output wavelength of not greater than 360 nm and an output power of at least 5 mW, having a peak output wavelength of 345 nm or less and an output power of at least 3 mW and/or a peak output wavelength of 330 nm or less and an output power of at least 0.3 mW at a current density of less than about 0.35 ?A/?m2 are also provided.
    Type: Application
    Filed: February 13, 2008
    Publication date: June 19, 2008
    Inventors: David Todd Emerson, Michael John Bergmann, Amber Abare, Kevin Haberern
  • Publication number: 20080135982
    Abstract: A semiconductor device including a semiconductor structure defining a mesa having a mesa surface and mesa sidewalls, and first and second passivation layers. The first passivation layer may be on at least portions of the mesa sidewalls, at least a portion of the mesa surface may be free of the first passivation layer, and the first passivation layer may include a first material. The second passivation layer may be on the first passivation layer, at least a portion of the mesa surface may be free of the second passivation layer, and the second passivation layer may include a second material different than the first material.
    Type: Application
    Filed: December 19, 2007
    Publication date: June 12, 2008
    Inventors: Kevin Ward Haberern, Raymond Rosado, Michael John Bergman, David Todd Emerson
  • Publication number: 20080121910
    Abstract: Semiconductor device structures are provided that are suitable for use in the fabrication of electronic devices such as light emitting diodes. The semiconductor device structures include a substrate having a roughened growth surface suitable for supporting the growth of an epitaxial region thereon. The device structure can include an epitaxial region having reduced defects and/or improved radiation extraction efficiency on the roughened growth surface of the substrate. The roughened growth surface of the substrate can have an average roughness Ra of at least about 1 nanometer (nm) and an average peak to valley height Rz of at least about 10 nanometers (nm).
    Type: Application
    Filed: November 28, 2006
    Publication date: May 29, 2008
    Inventors: Michael John Bergmann, Jason Hansen, David Todd Emerson, Kevin Ward Haberern
  • Patent number: D582866
    Type: Grant
    Filed: September 7, 2007
    Date of Patent: December 16, 2008
    Assignee: Cree, Inc.
    Inventors: John Edmond, James Ibbetson, Michael John Bergmann, Amber Christine Salter, David Todd Emerson, Ashay Chitnis, Bernd P. Keller, Kevin Haberern
  • Patent number: D583338
    Type: Grant
    Filed: September 7, 2007
    Date of Patent: December 23, 2008
    Assignee: Cree, Inc.
    Inventors: John Edmond, James Ibbetson, Michael John Bergmann, Amber Christine Salter, David Todd Emerson, Ashay Chitnis, Bernd P. Keller, Kevin Haberern
  • Patent number: D593968
    Type: Grant
    Filed: November 25, 2008
    Date of Patent: June 9, 2009
    Assignee: Cree, Inc.
    Inventors: John Edmond, James Ibbetson, Michael John Bergmann, Amber Christine Salter, David Todd Emerson, Ashay Chitnis, Bernd P. Keller, Kevin Haberern
  • Patent number: D595673
    Type: Grant
    Filed: January 19, 2007
    Date of Patent: July 7, 2009
    Assignee: Cree, Inc.
    Inventors: Christopher P. Hussell, David Todd Emerson
  • Patent number: D602450
    Type: Grant
    Filed: November 13, 2008
    Date of Patent: October 20, 2009
    Assignee: Cree, Inc.
    Inventors: John Edmond, James Ibbetson, Michael John Bergmann, Amber Christine Salter, David Todd Emerson, Ashay Chitnis, Bernd P. Keller, Kevin Haberern
  • LED
    Patent number: D605612
    Type: Grant
    Filed: February 4, 2009
    Date of Patent: December 8, 2009
    Assignee: Cree, Inc.
    Inventors: Christopher Parke Hussell, David Todd Emerson