Patents by Inventor Steven DenBaars

Steven 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).

  • Publication number: 20060049411
    Abstract: A method according to the present invention for fabricating high light extraction photonic devices comprising growing an epitaxial semiconductor structure on a substrate and depositing a first mirror layer on the epitaxial semiconductor structure such that the epitaxial semiconductor structure is sandwiched between the first mirror layer and the substrate. Flip-chip mounting the epitaxial semiconductor structure, with its first mirror and substrate on a submount such that the epitaxial semiconductor device structure is sandwiched between the submount and substrate. The substrate is then removed from the epitaxial structure by introducing an etch environment to the substrate. A second mirror layer is deposited on the epitaxial semiconductor structure such that the epitaxial semiconductor structure is sandwiched between the first and second mirror layers. A device according to the present invention comprising a resonant cavity light emitting diode (RCLED) mounted to a submount.
    Type: Application
    Filed: May 18, 2004
    Publication date: March 9, 2006
    Inventors: Shuji Nakamura, Steven DenBaars, John Edmond, Chuck Swoboda, Umesh Mishra
  • Publication number: 20060009006
    Abstract: A method for producing a wafer bonded structure between (Al, In, Ga)N and Zn(S,Se). A highly reflective and conductive distributed Bragg reflector (DBR) for relatively short optical wave lengths can be fabricated using Zn(S,Se) and MgS/(Zn, Cd)Se materials. Using wafer bonding techniques, these high-quality DBR structures can be combined with a GaN-based optical device structure.
    Type: Application
    Filed: July 6, 2005
    Publication date: January 12, 2006
    Applicant: The Regents of the University of California
    Inventors: Akihiko Murai, Lee McCarthy, Umesh Mishra, Steven DenBaars, Carsten Kruse, Stephan Figge, Detlef Hommel
  • Publication number: 20060008941
    Abstract: Highly planar non-polar a-plane GaN films are grown by hydride vapor phase epitaxy (HVPE).
    Type: Application
    Filed: July 15, 2003
    Publication date: January 12, 2006
    Applicant: BASF Aktiengesellschaft
    Inventors: Benjamin Haskell, Paul Fini, Shigemasa Matsuda, Michael Craven, Steven DenBaars, James Speck, Shuji Nakamura
  • Publication number: 20050247950
    Abstract: One embodiment of a method according to the present invention for fabricating a high light extraction photonic device comprises growing a lift-off layer on a substrate and growing an epitaxial semiconductor device structure on the lift-off layer such that the lift-off layer is sandwiched between said device structure and substrate. The epitaxial semiconductor structure comprises an emitter adapted to emit light in response to a bias. The device structure, lift-off layer and substrate is flip-chip mounted on a submount such that the epitaxial semiconductor device structure is sandwiched between the submount and lift-off layer. The lift-off layer is removed to separate the substrate from the device structure. Different removal methods can be used such as removal by a photo electrochemical etch or by illuminating the lift-off layer with laser light.
    Type: Application
    Filed: May 6, 2004
    Publication date: November 10, 2005
    Inventors: Shuji Nakamura, Steven DenBaars
  • Publication number: 20050245095
    Abstract: A method of growing highly planar, fully transparent and specular m-plane gallium nitride (GaN) films. The method provides for a significant reduction in structural defect densities via a lateral overgrowth technique. High quality, uniform, thick m-plane GaN films are produced for use as substrates for polarization-free device growth.
    Type: Application
    Filed: May 31, 2005
    Publication date: November 3, 2005
    Applicant: The Regents of the University of California
    Inventors: Benjamin Haskell, Melvin McLaurin, Steven DenBaars, James Speck, Shuji Nakamura
  • Publication number: 20050214992
    Abstract: A method for the fabrication of nonpolar indium gallium nitride (InGaN) films as well as nonpolar InGaN-containing device structures using metalorganic chemical vapor deposition (MOVCD). The method is used to fabricate nonpolar InGaN/GaN violet and near-ultraviolet light emitting diodes and laser diodes.
    Type: Application
    Filed: May 6, 2005
    Publication date: September 29, 2005
    Inventors: Arpan Chakraborty, Benjamin Haskell, Stacia Keller, James Speck, Steven Denbaars, Shuji Nakamura, Umesh Mishra
  • Publication number: 20050040385
    Abstract: A method for forming non-polar (Al,B,In,Ga)N quantum well and heterostructure materials and devices. Non-polar (11{overscore (2)}0) a-plane GaN layers are grown on an r-plane (1{overscore (1)}02) sapphire substrate using MOCVD. These non-polar (11{overscore (2)}0) a-plane GaN layers comprise templates for producing non-polar (Al,B,In,Ga)N quantum well and heterostructure materials and devices.
    Type: Application
    Filed: April 15, 2003
    Publication date: February 24, 2005
    Inventors: Michael Craven, Stacia Keller, Steven Denbaars, Tal Margalith, James Speck, Shuji Nakamura, Umesh Mishra
  • Patent number: 6821804
    Abstract: This invention describes new LEDs having light extraction structures on or within the LED to increase its efficiency. The new light extraction structures provide surfaces for reflecting, refracting or scattering light into directions that are more favorable for the light to escape into the package. The structures can be arrays of light extraction elements or disperser layers. The light extraction elements can have many different shapes and are placed in many locations to increase the efficiency of the LED over conventional LEDs. The disperser layers provide scattering centers for light and can be placed in many locations as well. The new LEDs with arrays of light extraction elements are fabricated with standard processing techniques making them highly manufacturable at costs similar to standard LEDs. The new LEDs with disperser layers are manufactured using new methods and are also highly manufacturable.
    Type: Grant
    Filed: September 17, 2003
    Date of Patent: November 23, 2004
    Assignee: Cree, Inc.
    Inventors: Brian Thibeault, Michael Mack, Steven DenBaars
  • Publication number: 20040175939
    Abstract: The present invention discloses a susceptor mounting assembly for holding semiconductor wafers in an MOCVD reactor during growth of epitaxial layers on the wafers, that is particularly adapted for mounting a susceptor in an inverted type reactor chamber. It includes a tower having an upper and lower end with the upper end mounted to the top inside surface of the reactor chamber and a susceptor is arranged at the tower's lower end. Semiconductor wafers are held adjacent to the susceptor such that heat from the susceptor passes into wafers. A second embodiment of a susceptor mounting assembly according to the invention also comprises a tower having an upper and lower end. The tower's upper end is mounted to the top inside surface of the reactor chamber. A susceptor is housed within a cup and the cup is mounted to the tower's lower end.
    Type: Application
    Filed: March 4, 2003
    Publication date: September 9, 2004
    Applicant: Cree Lighting Company.
    Inventors: Shuji Nakamura, Steven DenBaars, Max Batres, Michael Coulter
  • Publication number: 20040060518
    Abstract: A semiconductor fabrication reactor according to the invention comprises a rotatable susceptor mounted to the top of a reactor chamber. One or more wafers are mounted to a surface of the susceptor and the rotation of the susceptor causes the wafers to rotate within the chamber. A heater heats the susceptor and a chamber gas inlet allows semiconductor growth gasses into the reactor chamber to deposit semiconductor material on said wafers. A chamber gas outlet is included to allow growth gasses to exit the chamber. In a preferred embodiment, the inlet is at or below the level of said wafers and the outlet is preferably at or above the level of the wafers. A semiconductor fabrication system according to the invention comprises a source of gasses for forming epitaxial layers on wafers and a source of gasses for dopants in said epitaxial layers.
    Type: Application
    Filed: September 27, 2002
    Publication date: April 1, 2004
    Applicant: CREE LIGHTING COMPANY
    Inventors: Shuji Nakamura, Steven DenBaars, Max Batres, Michael Coulter
  • Publication number: 20040041164
    Abstract: This invention describes new LEDs having light extraction structures on or within the LED to increase its efficiency. The new light extraction structures provide surfaces for reflecting, refracting or scattering light into directions that are more favorable for the light to escape into the package. The structures can be arrays of light extraction elements or disperser layers. The light extraction elements can have many different shapes and are placed in many locations to increase the efficiency of the LED over conventional LEDs. The disperser layers provide scattering centers for light and can be placed in many locations as well. The new LEDs with arrays of light extraction elements are fabricated with standard processing techniques making them highly manufacturable at costs similar to standard LEDs. The new LEDs with disperser layers are manufactured using new methods and are also highly manufacturable.
    Type: Application
    Filed: September 17, 2003
    Publication date: March 4, 2004
    Applicant: Cree Lighting Company
    Inventors: Brian Thibeault, Michael Mack, Steven DenBaars
  • Patent number: 6657236
    Abstract: This invention describes new LEDs having light extraction structures on or within the LED to increase its efficiency. The new light extraction structures provide surfaces for reflecting, refracting or scattering light into directions that are more favorable for the light to escape into the package. The structures can be arrays of light extraction elements or disperser layers. The light extraction elements can have many different shapes and are placed in many locations to increase the efficiency of the LED over conventional LEDs. The disperser layers provide scattering centers for light and can be placed in many locations as well. The new LEDs with arrays of light extraction elements are fabricated with standard processing techniques making them highly manufacturable at costs similar to standard LEDs. The new LEDs with disperser layers are manufactured using new methods and are also highly manufacturable.
    Type: Grant
    Filed: November 28, 2000
    Date of Patent: December 2, 2003
    Assignee: Cree Lighting Company
    Inventors: Brian Thibeault, Michael Mack, Steven DenBaars
  • Publication number: 20030209719
    Abstract: A susceptor for holding semiconductor wafers in an MOCVD reactor during growth of epitaxial layers on the wafers is disclosed. The susceptor comprises a base structure made of a material having low thermal conductivity at high temperature, and has one or more plate holes to house heat transfer plugs. The plugs are made of a material with high thermal conductivity at high temperatures to transfer heat to the semiconductor wafers. A metalorganic organic chemical vapor deposition reactor is also disclosed utilizing a susceptor according to the present invention.
    Type: Application
    Filed: May 13, 2002
    Publication date: November 13, 2003
    Applicant: CREE LIGHTING COMPANY
    Inventors: Shuji Nakamura, Steven DenBaars, Max Batres, Michael Coulter
  • Patent number: 6410942
    Abstract: This invention describes new LED structures that provide increased light extraction efficiency. The new LED structures include arrays of electrically interconnected micro-LEDs that have and active layer sandwiched between two oppositely doped layer. The micro-LEDs are formed on a first spreader layer with the bottom layer of the micro-LEDs in contact with the first spreader. A second spreader layer is formed over the micro-LEDs and in contact with their top layer. The first spreader layer is electrically isolated from the second spreader layer. Each of the spreader layers has a contact and when a bias is applied across the contacts, current spreads to the micro-LEDs and they emit light. The efficiency of the new LED is increased by the increased emission surface of the micro-LEDs. Light from each of the micro-LEDs active layer will reach a surface after travelling only a short distance, reducing total internal reflection of the light.
    Type: Grant
    Filed: November 14, 2000
    Date of Patent: June 25, 2002
    Assignee: Cree Lighting Company
    Inventors: Brian Thibeault, Steven DenBaars