Patents Represented by Attorney, Agent or Law Firm Mark E. Schmidt
  • Patent number: 6570190
    Abstract: The invention is a method for designing semiconductor light emitting devices such that the side surfaces (surfaces not parallel to the epitaxial layers) are formed at preferred angles relative to vertical (normal to the plane of the light-emitting active layer) to improve light extraction efficiency and increase total light output efficiency. Device designs are chosen to improve efficiency without resorting to excessive active area-yield loss due to shaping. As such, these designs are suitable for low-cost, high-volume manufacturing of semiconductor light-emitting devices with improved characteristics.
    Type: Grant
    Filed: December 6, 2000
    Date of Patent: May 27, 2003
    Assignee: Lumileds Lighting, U.S., LLC
    Inventors: Michael R Krames, Fred A Kish, Jr., Tun S Tan
  • Patent number: 6420199
    Abstract: Light emitting devices having a vertical optical path, e.g. a vertical cavity surface emitting laser or a resonant cavity light emitting or detecting device, having high quality mirrors may be achieved using wafer bonding or metallic soldering techniques. The light emitting region interposes one or two reflector stacks containing dielectric distributed Bragg reflectors (DBRs). The dielectric DBRs may be deposited or attached to the light emitting device. A host substrate of GaP, GaAs, InP, or Si is attached to one of the dielectric DBRs. Electrical contacts are added to the light emitting device.
    Type: Grant
    Filed: August 6, 2001
    Date of Patent: July 16, 2002
    Assignee: LumiLeds Lighting, U.S., LLC
    Inventors: Carrie Carter Coman, R. Scott Kern, Fred A. Kish, Jr., Michael R Krames, Arto V. Nurmikko, Yoon-Kyu Song
  • Patent number: 6417019
    Abstract: A method of fabricating a light emitting device includes providing a light emitting diode that emits primary light, and locating proximate to the light emitting diode a (Sr1−u−v−xMguCavBax)(Ga2−y−zAlyInzS4):Eu2+ phosphor material capable of absorbing at least a portion of the primary light and emitting secondary light having a wavelength longer than a wavelength of the primary light. The composition of the phosphor material can be selected to determine the wavelengths of the secondary light. In one embodiment, the light emitting device includes the phosphor material dispersed as phosphor particles in another material disposed around the light emitting diode. In another embodiment, the light emitting device includes the phosphor material deposited as a phosphor film on at least one surface of the light emitting diode.
    Type: Grant
    Filed: April 4, 2001
    Date of Patent: July 9, 2002
    Assignee: LumiLeds Lighting, U.S., LLC
    Inventors: Gerd O. Mueller, Regina B. Mueller-Mach
  • Patent number: 6351069
    Abstract: A light emitting device and a method of fabricating the device utilize a supplementary fluorescent material that radiates secondary light in the red spectral region of the visible light spectrum to increase the red color component of the composite output light. The secondary light from the supplementary fluorescent material allows the device to produce “white” output light that is well-balanced with respect to color for true color rendering applications. The supplementary fluorescent material is included in a fluorescent layer that is positioned between a die and a lens of the device. The die is preferably a GaN based die that emits light having a peak wavelength of 470 nm. The fluorescent layer also includes a main fluorescent material. Preferably, the main fluorescent material is Cerium (Ce) activated and Gadolinium (Gd) doped Yttrium Aluminum Garnet (YAG) phosphor (“Ce:YAG phosphor”).
    Type: Grant
    Filed: February 18, 1999
    Date of Patent: February 26, 2002
    Assignee: LumiLeds Lighting, U.S., LLC
    Inventors: Christopher H. Lowery, Gerd Mueller, Regina Mueller
  • Patent number: 6323938
    Abstract: A method of characterizing photolithographic tool performance is presented. Variations in performance over an image or exposure field are evaluated and contributions to the variation due to the partial coherence factor of the tool separated from other contributing factors. Methods of determining the relative magnitude of these variations is provided and a photolithographic tool that incorporates these methods described.
    Type: Grant
    Filed: April 27, 1998
    Date of Patent: November 27, 2001
    Assignee: Nikon Precision, Inc.
    Inventors: Ilya Grodnensky, Toshihiro Sasaya
  • Patent number: 6320206
    Abstract: Light emitting devices having a vertical optical path, e.g. a vertical cavity surface emitting laser or a resonant cavity light emitting or detecting device, having high quality mirrors may be achieved using wafer bonding or metallic soldering techniques. The light emitting region interposes one or two reflector stacks containing dielectric distributed Bragg reflectors (DBRs). The dielectric DBRs may be deposited or attached to the light emitting device. A host substrate of GaP, GaAs, InP, or Si is attached to one of the dielectric DBRs. Electrical contacts are added to the light emitting device.
    Type: Grant
    Filed: February 5, 1999
    Date of Patent: November 20, 2001
    Assignee: LumiLeds Lighting, U.S., LLC
    Inventors: Carrie Carter Coman, R. Scott Kern, Fred A. Kish, Jr., Michael R Krames, Arto V. Nurmikko, Yoon-Kyu Song
  • Patent number: 6296906
    Abstract: Dielectric films in integrated circuits are annealed in the presence of water to improve their thermal stability and their resistance to damage from ultraviolet radiation.
    Type: Grant
    Filed: September 30, 1999
    Date of Patent: October 2, 2001
    Assignee: Novellus Systems, Inc.
    Inventors: Jim Stimmell, Joe Laia, Ajay Saproo
  • Patent number: 6274399
    Abstract: In the present invention, an interfacial layer is added to a light-emitting diode or laser diode structure to perform the role of strain engineering and impurity gettering. A layer of GaN or AlxInyGa1−x−yN (0≦x≦1, 0≦y≦1) doped with Mg, Zn, Cd can be used for this layer. Alternatively, when using AlxInyGa1−x−yN (x>0), the layer may be undoped. The interfacial layer is deposited directly on top of the buffer layer prior to the growth of the n-type (GaN:Si) layer and the remainder of the device structure. The thickness of the interface layer varies from 0.01-10.0 &mgr;m.
    Type: Grant
    Filed: September 6, 2000
    Date of Patent: August 14, 2001
    Assignee: LumiLeds Lighting, U.S. LLC
    Inventors: R. Scott Kern, Changhua Chen, Werner Goetz, Chihping Kuo
  • Patent number: 6252222
    Abstract: A laser beam is used to probe an integrated circuit device under test. A single laser provides a single laser pulse which is divided into two pulses, both of which are incident upon the device under test. After the two pulses interact with the device under test, the two pulses are separated and detected by two photo detectors. The electrical signals output by the photo detectors are then subtracted, which cancels out any common mode noise induced on both pulses including noise due to mechanical vibration of the device under test and also any noise from the laser. The difference signal can be used to reproduce a time varying signal in the device under test.
    Type: Grant
    Filed: January 13, 2000
    Date of Patent: June 26, 2001
    Assignee: Schlumberger Technologies, Inc.
    Inventors: Steven A. Kasapi, Chun-Cheng Tsao, Seema Somani
  • Patent number: 6201264
    Abstract: For AlGaAs LEDs the confining layers adjoining the active layer possess the highest Al composition. From failure analysis of non-passivated, WHTOL-aged, AlGaAs LEDs, it was discovered that corrosion occurs the fastest at the exposed surfaces of the high Al-content confining layers. By placing a high-quality native oxide at the exposed surfaces of the high Al-content confining layers which protect from the formation of the ‘poor’ oxide, it is possible for LEDs to retain essentially their same light output after 2,000 hours of WHTOL testing. Further, it is possible to improve carrier confinement, carrier injection, wave guiding, and other properties by increasing the Al-content of different layers.
    Type: Grant
    Filed: January 14, 1999
    Date of Patent: March 13, 2001
    Assignee: LumiLeds Lighting, U.S., LLC
    Inventors: Reena Khare, Fred A. Kish
  • Patent number: 6194742
    Abstract: In the present invention, an interfacial layer is added to a light-emitting diode or laser diode structure to perform the role of strain engineering and impurity gettering. A layer of GaN or AlxInyGal1-x-yN (0≦x≦1, 0≦y≦1) doped with Mg, Zn, Cd can be used for this layer. Alternatively, when using AlxInyGa1-x-yN (x>0), the layer may be undoped. The interfacial layer is deposited directly on top of the buffer layer prior to the growth of the n-type (GaN:Si) layer and the remainder of the device structure. The thickness of the interfacial layer varies from 0.01-10.0 &mgr;m.
    Type: Grant
    Filed: June 5, 1998
    Date of Patent: February 27, 2001
    Assignee: LumiLeds Lighting, U.S., LLC
    Inventors: R. Scott Kern, Changhua Chen, Werner Goetz, Chihping Kuo
  • Patent number: 6191429
    Abstract: Improvements in a focusing apparatus having an objective optical system for optically manufacturing a workpiece, forming a desired pattern on a surface of a workpiece or inspecting a pattern on a workpiece and used to adjust the state of focusing between the surface of the workpiece and the objective optical system. The focusing apparatus has a first detection system having a detection area at a first position located outside the field of the objective optical system, a second detection system having a detection area at a second position located outside the field of the objective optical system and spaced apart from the first position, and a third detection system having a detection area at a third position located outside the field of the objective optical system and spaced apart from each of the first and second positions.
    Type: Grant
    Filed: April 6, 1999
    Date of Patent: February 20, 2001
    Assignee: Nikon Precision Inc.
    Inventor: Kyoichi Suwa