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: 20070111488
    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: January 9, 2007
    Publication date: May 17, 2007
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Arpan Chakraborty, Benjamin Haskell, Stacia Keller, James Speck, Steven DenBaars, Shuji Nakamura, Umesh Mishra
  • Publication number: 20070102721
    Abstract: An (Al, Ga, In)N and ZnO direct wafer bonded light emitting diode (LED) combined with a shaped plastic optical element, in which the directional light from the ZnO cone, or from any high refractive index material in contact with the LED surface, entering the shaped plastic optical element is extracted to air.
    Type: Application
    Filed: November 6, 2006
    Publication date: May 10, 2007
    Inventors: Steven DenBaars, Shuji Nakamura, Hisashi Masui, Natalie Fellows, Akihiko Murai
  • Publication number: 20070096127
    Abstract: A spontaneously light emitting nitride-based active region placed within a micro-cavity bounded by a first mirror and a second mirror, wherein the micro-cavity has been thinned to a resonant thickness within a micro-cavity regime.
    Type: Application
    Filed: August 25, 2006
    Publication date: May 3, 2007
    Inventors: P. Pattison, Rajat Sharma, Steven DenBaars, Shuji Nakamura
  • Publication number: 20070093073
    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: June 1, 2006
    Publication date: April 26, 2007
    Inventors: Robert Farrell, Troy Baker, Arpan Chakraborty, Benjamin Haskell, P. Pattison, Rajat Sharma, Umesh Mishra, Steven DenBaars, James Speck, Shuji Nakamura
  • Publication number: 20070018183
    Abstract: A light emitting diode (LED) includes a p-type layer of material, an n-type layer of material and an active layer between the p-type layer and the n-type layer. A roughened layer of transparent material is adjacent one of the p-type layer of material and the n-type layer of material. The roughened layer of transparent material has a refractive index close to or substantially the same as the refractive index of the material adjacent the layer of transparent material, and may be a transparent oxide material or a transparent conducting material. An additional layer of conductive material may be between the roughened layer and the n-type or p-type layer.
    Type: Application
    Filed: July 21, 2005
    Publication date: January 25, 2007
    Inventors: Steven Denbaars, James Ibbetson, Shuji Nakamura
  • Publication number: 20070001186
    Abstract: An (Al, Ga, In)N and ZnO direct wafer bonded light emitting diode (LED), wherein light passes through electrically conductive ZnO. Flat and clean surfaces are prepared for both the (Al, Ga, In)N and ZnO wafers. A wafer bonding process is then performed between the (Al, Ga, In)N and ZnO wafers, wherein the (Al, Ga, In)N and ZnO wafers are joined together and then wafer bonded in a nitrogen ambient under uniaxial pressure at a set temperature for a set duration. After the wafer bonding process, ZnO is shaped for increasing light extraction from inside of LED.
    Type: Application
    Filed: June 16, 2006
    Publication date: January 4, 2007
    Inventors: Akihiko Murai, Christina Chen, Daniel Thompson, Lee McCarthy, Steven DenBaars, Shoji Nakamura, Umesh Mishra
  • Publication number: 20060284206
    Abstract: A polarized light emitting diode (LED) includes a marker indicating a polarization direction. A package for the LED also includes a marker indicating the polarization direction. The markers on the LED and package are used for mutual alignment, wherein the LED is attached in a favorable orientation with respect to a package, so that the polarization direction of emitted light from the package is apparent. The marker is placed on the LED before die separation and the marker is placed on the package before alignment. The marker on the LED comprises a photolithographic pattern, an asymmetric die shape, a notch on the die, or a scratch on the die, while the marker on the package comprises an electrode shape or pattern, an asymmetric package shape, a notch on the package, or a scratch on the package. Finally, the LED or package may be installed in an external circuit or system that also indicates the polarization direction.
    Type: Application
    Filed: June 21, 2006
    Publication date: December 21, 2006
    Inventors: Hisashi Masui, Shuji Nakamura, Steven DenBaars
  • Publication number: 20060278865
    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: June 21, 2006
    Publication date: December 14, 2006
    Inventors: Michael Craven, Stacia Keller, Steven DenBaars, Tal Margalith, James Speck, Shuji Nakamura, Umesh Mishra
  • Publication number: 20060270087
    Abstract: A method of growing planar non-polar m-plane III-Nitride material, such as an m-plane gallium nitride (GaN) epitaxial layer, wherein the III-Nitride material is grown on a suitable substrate, such as an m-plane silicon carbide (m-SiC) substrate, using metalorganic chemical vapor deposition (MOCVD). The method includes performing a solvent clean and acid dip of the substrate to remove oxide from the surface, annealing the substrate, growing a nucleation layer such as an aluminum nitride (AIN) on the annealed substrate, and growing the non-polar m-plane III-Nitride epitaxial layer on the nucleation layer using MOCVD.
    Type: Application
    Filed: May 31, 2006
    Publication date: November 30, 2006
    Inventors: Bilge Imer, James Speck, Steven DenBaars
  • Publication number: 20060269390
    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: July 6, 2006
    Publication date: November 30, 2006
    Inventors: Shuji Nakamura, Steven DenBaars, Max Batres, Michael Coulter
  • Publication number: 20060270076
    Abstract: A method of reducing threading dislocation densities in non-polar such as a-{11-20} plane and m-{1-100} plane or semi-polar such as {10-1n} plane III-Nitrides by employing lateral epitaxial overgrowth from sidewalls of etched template material through a patterned mask. The method includes depositing a patterned mask on a template material such as a non-polar or semi polar GaN template, etching the template material down to various depths through openings in the mask, and growing non-polar or semi-polar III-Nitride by coalescing laterally from the tops of the sidewalls before the vertically growing material from the trench bottoms reaches the tops of the sidewalls. The coalesced features grow through the openings of the mask, and grow laterally over the dielectric mask until a fully coalesced continuous film is achieved.
    Type: Application
    Filed: May 31, 2006
    Publication date: November 30, 2006
    Inventors: Bilge Imer, James Speck, Steven DenBaars
  • Publication number: 20060255347
    Abstract: A light emitting diode (LED) grown on a substrate doped with one or more rare earth or transition element. The dopant ions absorb some or all of the light from the LED's active layer, pumping the electrons on the dopant ion to a higher energy state. The electrons are naturally drawn to their equilibrium state and they emit light at a wavelength that depends on the type of dopant ion. The invention is particularly applicable to nitride based LEDs emitting UV light and grown on a sapphire substrate doped with chromium. The chromium ions absorb the UV light, exciting the electrons on ions to a higher energy state. When they return to their equilibrium state they emit red light and some of the red light will emit from the LED's surface. The LED can also have active layers that emit green and blue and UV light, such that the LED emits green, blue, red light and UV light which combines to create white light.
    Type: Application
    Filed: July 10, 2006
    Publication date: November 16, 2006
    Inventors: Steven DenBaars, Eric Tarsa, Michael Mack, Bernd Keller, Brian Thibeault
  • Patent number: 7122844
    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: Grant
    Filed: May 13, 2002
    Date of Patent: October 17, 2006
    Assignee: Cree, Inc.
    Inventors: Shuji Nakamura, Steven DenBaars, Max Batres, Michael Coulter
  • Publication number: 20060202226
    Abstract: A single or multi-color light emitting diode (LED) with high extraction efficiency is comprised of a substrate, a buffer layer formed on the substrate, one or more patterned layers deposited on top of the buffer layer, and one or more active layers formed on or between the patterned layers, for example by Lateral Epitaxial Overgrowth (LEO), and including one or more light emitting species, such as quantum wells. The patterned layers include a patterned, perforated or pierced mask made of insulating, semiconducting or metallic material, and materials filling holes in the mask. The patterned layer acts as an optical confining layer due to a contrast of a refractive index with the active layer and/or as a buried diffraction grating due to variation of a refractive index between the mask and the material filling the holes in the mask.
    Type: Application
    Filed: February 28, 2005
    Publication date: September 14, 2006
    Inventors: Claude Weisbuch, Aurelien David, James Speck, Steven DenBaars
  • Publication number: 20060205199
    Abstract: A method for growing planar, semi-polar nitride film on a miscut spinel substrate, in which a large area of the planar, semi-polar nitride film is parallel to the substrate's surface.
    Type: Application
    Filed: March 10, 2006
    Publication date: September 14, 2006
    Inventors: Troy Baker, Benjamin Haskell, Paul Fini, Steven DenBaars, James Speck, Shuji Nakamura
  • Publication number: 20060194359
    Abstract: A structure using integrated optical elements is comprised of a substrate, a buffer layer grown on the substrate, one or more patterned layers formed on the buffer layer and one or more active layers formed on or between the patterned layers, for instance by Lateral Epitaxial Overgrowth (LEO), and including one or more light emitting species. The patterned layer comprises a mask (made of insulating, semiconducting or metallic material) and material filling holes in the mask. The patterned layer, due to a large index difference with the active layer and/or variations of a refractive index between the mask and materials filling holes in the mask, acts as an optical confinement layer, a mirror, a diffraction grating, a wavelength selective element, a beam shaping element or a beam directing element.
    Type: Application
    Filed: February 28, 2005
    Publication date: August 31, 2006
    Inventors: Claude Weisbuch, Aurelien David, James Speck, Steven DenBaars
  • Publication number: 20060192217
    Abstract: A high efficiency, and possibly highly directional, light emitting diode (LED) with an optimized photonic crystal extractor. The LED is comprised of a substrate, a buffer layer grown on the substrate (if needed), an active layer including emitting species, one or more optical confinement layers that tailor the structure of the guided modes in the LED, and one or more diffraction gratings, wherein the diffraction gratings are two-dimensional photonic crystal extractors. The substrate may be removed and metal layers may be deposited on the buffer layer, photonic crystal and active layer, wherein the metal layers may function as a mirror, an electrical contact, and/or an efficient diffraction grating.
    Type: Application
    Filed: February 28, 2005
    Publication date: August 31, 2006
    Inventors: Aurelien David, Claude Weisbuch, Steven DenBaars
  • Publication number: 20060163586
    Abstract: An LED having a p-type layer of material with an associated p-contact, an n-type layer of material with an associated n-contact and an active region between the p-type layer and the n-type layer, includes a confinement structure that is formed within one of the p-type layer of material and the n-type layer of material. The confinement structure is generally aligned with the contact on the top and primary emission surface of the LED and substantially prevents the emission of light from the area of the active region that is coincident with the area of the confinement structure and the top-surface contact. The LED may include a roughened emitting-side surface to further enhance light extraction.
    Type: Application
    Filed: January 24, 2005
    Publication date: July 27, 2006
    Inventors: Steven Denbaars, Shuji Nakamura, Max Batres
  • Publication number: 20060128124
    Abstract: Lateral epitaxial overgrowth (LEO) of non-polar a-plane gallium nitride (GaN) films by hydride vapor phase epitaxy (HVPE) results in significantly reduced defect density.
    Type: Application
    Filed: July 15, 2003
    Publication date: June 15, 2006
    Inventors: Benjamin Haskell, Michael Craven, Paul Fini, Steven DenBaars, James Speck, Shuji Nakamura
  • Publication number: 20060054905
    Abstract: A white, single or multi-color light emitting diode (LED) includes a mirror for reflecting photons within the LED; a first active region, adjacent the mirror, including one or more current-injected layers for emitting photons when electrically biased in a forward direction; a second active region, adjacent the first active region, including one or more optically-pumped layers for emitting photons, wherein the optically-pumped layers are optically excited by the photons emitted by the current-injected layers, thereby recycling guided modes; and an output interface, adjacent the second active region, for allowing the photons emitted by the optically-pumped layers to escape the LED as emitted light.
    Type: Application
    Filed: September 10, 2004
    Publication date: March 16, 2006
    Inventors: Carole Schwach, Claude Weisbuch, Steven DenBaars, Henri Benisty, Shuji Nakamura