Patents by Inventor Michael N. Alexander

Michael N. Alexander 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: 6306739
    Abstract: In this invention, one or more metal-containing sources and one or more ammonium halides are heated such that they evaporate into a vacuum environment (except that, in MOMBE, a beam of the organometallic source compound may be created by other means) and made to impinge on a substrate. The materials interact on the substrate to form a film of the desired nitride compound or alloy; the substrate usually will be heated to promote chemical reaction and good film properties such as high crystallinity. Other sources—to provide dopant impurities like silicon or magnesium, for example—would be part of a deposition system envisioned in this invention. Multiple film layers, including quantum wells and superlattices, may be formed using this method, in addition to a single film.
    Type: Grant
    Filed: April 27, 1999
    Date of Patent: October 23, 2001
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventor: Michael N. Alexander
  • Patent number: 5981949
    Abstract: The invention provides method and apparatus for fast, accurate, and nondestructive imaging of defects and determining defect densities in solid materials including a semiconductor wafer. A wafer is illuminated on one side by an infrared (IR) source and a camera is placed on the other side of the wafer, to detect IR radiation that is transmitted through such wafer. The inventive method employs an imaging camera, e.g. a focal plane array camera, to image the so illuminated wafer. The wafer material must be substantially transparent in the camera bandwidth but can contain defects that absorb or scatter radiation in such bandwidth. Camera filters are used, for example, to select specific wavelengths or bands of wavelengths, to detect and image precipitates, subsurface defects, residual damage from polishing and other defects.
    Type: Grant
    Filed: November 3, 1997
    Date of Patent: November 9, 1999
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Darin J. Leahy, Maxwell M. Chi, Jonathan M. Mooney, Michael N. Alexander
  • Patent number: 5760327
    Abstract: A high temperature superconducting material is incorporated onto a vehicle for the purpose of reflecting electromagnetic waves while superconducting. The vehicle may be chaff, a decoy, an electronic pod, a satellite, or a space vehicle. Heating and/or cooling is used to control the superconductivity state of the material. By selective use of the material and the substrate to which it is attached, the radar as well as the IR signatures can be altered.
    Type: Grant
    Filed: October 4, 1994
    Date of Patent: June 2, 1998
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventor: Michael N. Alexander
  • Patent number: 5169557
    Abstract: A process for production of lanthanum cerium aluminate phosphors represented by the formulaLa.sub.1-x Ce.sub.x Al.sub.y O.sub.(3/2)(y+1)wherein 0.10<x<1 and 11.0.ltoreq.y.ltoreq.12.5, the phosphor exhibiting a predominantly blue peak emission. Lanthanum (III) oxide, cerium (IV) oxide, and aluminum hydroxide are blended together in the desired ratios, then precalcined in air at about 850.degree. C. The precalcined product is then fired in a reducing atmosphere at about 1600.degree.-1800.degree. C. for about 3-4 hours, pulverized, refired in a reducing atmosphere at about 1600.degree.-1800.degree. C. for about 3-4 hours, and again pulverized to form the phosphor.
    Type: Grant
    Filed: March 20, 1990
    Date of Patent: December 8, 1992
    Inventors: A. Gary Sigai, Michael N. Alexander, Charles W. Struck
  • Patent number: 5105121
    Abstract: Lanthanum cerium aluminate phosphor compositions are disclosed wherein the formula for the phosphor can be characterized as follows:La.sub.1-x Ce.sub.x Al.sub.y O.sub.(3/2)(y+1)wherein 0<x<1 and 11.ltoreq.y.ltoreq.13.8.
    Type: Grant
    Filed: August 23, 1989
    Date of Patent: April 14, 1992
    Assignee: GTE Laboratories Incorporated
    Inventors: Gary A. Sigai, Michael N. Alexander, Charles W. Struck
  • Patent number: 4937503
    Abstract: A fluorescent light source based on a phosphor excited by a molecular discharge is described. The fluorescent light source comprises a capacitively coupled compact fluorescent lamp coated with a manganese doped magnesium aluminate phosphor on the inside surface of the lamp envelope. The compact fluorscent lamp produces a plasma which emits 206 nm radiation from the molecular discharge of the iodine containing molecular vapors and inert gas fill which in turn excites the phosphor to emit visible light.
    Type: Grant
    Filed: April 11, 1988
    Date of Patent: June 26, 1990
    Assignee: GTE Laboratories Incorporated
    Inventors: A. Gary Sigai, Walter P. Lapatovich, Michael N. Alexander
  • Patent number: 4874984
    Abstract: A fluorescent lamp based on a phosphor excited by a molecular discharge is described. The fluorescent lamp comprises a fluorescent lamp coated with a manganese doped magnesium aluminate phosphor on the inside surface of the lamp envelope. The fluorescent lamp contains corrosion resistant filamentary electron emitting electrodes. The fluorescent lamp produces a plasma which emits 206 nm radiation from the molecular discharge of the iodine containing molecular vapors and inert gas fill which in turn excites the phosphor to emit visible light.
    Type: Grant
    Filed: April 11, 1988
    Date of Patent: October 17, 1989
    Assignee: GTE Laboratories Incorporated
    Inventors: A. Gary Sigai, Walter P. Lapatovich, Michael N. Alexander
  • Patent number: 4818433
    Abstract: Lanthanum cerium aluminate phosphor compositions are disclosed wherein the formula for the phosphor can be characterized as follows:La.sub.1-x Ce.sub.x Al.sub.y O.sub.(3/2)(y+1)wherein O<x<1 and 11.ltoreq.y.ltoreq.13.8.
    Type: Grant
    Filed: June 3, 1988
    Date of Patent: April 4, 1989
    Assignee: GTE Laboratories Incorporated
    Inventors: A. Gary Sigai, Michael N. Alexander, Charles W. Struck
  • Patent number: 4748391
    Abstract: A method for preparing a barium lanthanum silicate oxyapatite europium activated phosphor and a barium lanthanum silicate oxyapatite manganese 2+ and europium 2+ or europium 2+ activated phosphor having a yellow green emission when activated by 254 nm excitation comprises the steps of forming a water slurry of the raw materials followed by calcining at approximately 1050.degree. C. to form a powder. The powder is then heated to approximately 1500.degree. C. in a reducing atmosphere to form the phosphor having a yellow green emission activated by a 254 nm excitation. Fluorescent lamps containing the yellow green emitting phosphors are described.
    Type: Grant
    Filed: December 18, 1986
    Date of Patent: May 31, 1988
    Assignee: GTE Laboratories Incorporated
    Inventors: A. Gary Sigai, Michael N. Alexander
  • Patent number: 4050009
    Abstract: An improvement in nuclear magnetic resonance spectrometer apparatus and one onsisting of a spectrometer which utilizes separate materials containing, respectively, sample and detector spin systems as opposed to one in which the sample and detector spins are contained in the same single material.
    Type: Grant
    Filed: January 9, 1976
    Date of Patent: September 20, 1977
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Paul L. Sagalyn, Michael N. Alexander