Patents by Inventor Frederick Joseph Walker

Frederick Joseph Walker 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: 6103008
    Abstract: A crystalline thin-film structure suited for use in any of an number of electro-optic applications, such as a phase modulator or a component of an interferometer, includes a semiconductor substrate of silicon and a ferroelectric, optically-clear thin film of the perovskite BaTiO.sub.3 overlying the surface of the silicon substrate. The BaTiO.sub.3 thin film is characterized in that substantially all of the dipole moments associated with the ferroelectric film are arranged substantially parallel to the surface of the substrate to enhance the electro-optic qualities of the film.
    Type: Grant
    Filed: July 30, 1998
    Date of Patent: August 15, 2000
    Assignee: UT-Battelle, LLC
    Inventors: Rodney A. McKee, Frederick Joseph Walker
  • Patent number: 6093242
    Abstract: A semiconductor structure and device for use in a semiconductor application utilizes a substrate of semiconductor-based material, such as silicon, and a thin film of a crystalline oxide whose unit cells are capable of exhibiting anisotropic behavior overlying the substrate surface. Within the structure, the unit cells of the crystalline oxide are exposed to an in-plane stain which influences the geometric shape of the unit cells and thereby arranges a directional-dependent quality of the unit cells in a predisposed orientation relative to the substrate. This predisposition of the directional-dependent quality of the unit cells enables the device to take beneficial advantage of characteristics of the structure during operation.
    Type: Grant
    Filed: July 30, 1998
    Date of Patent: July 25, 2000
    Assignee: UT-Battelle, LLC
    Inventors: Rodney Allen McKee, Frederick Joseph Walker
  • Patent number: 6023082
    Abstract: A crystalline structure and a semiconductor device includes a substrate of a semiconductor-based material and a thin film of an anisotropic crystalline material epitaxially arranged upon the surface of the substrate so that the thin film couples to the underlying substrate and so that the geometries of substantially all of the unit cells of the thin film are arranged in a predisposed orientation relative to the substrate surface. The predisposition of the geometries of the unit cells of the thin film is responsible for a predisposed orientation of a directional-dependent quality, such as the dipole moment, of the unit cells. The predisposed orientation of the unit cell geometries are influenced by either a stressed or strained condition of the lattice at the interface between the thin film material and the substrate surface.
    Type: Grant
    Filed: July 30, 1998
    Date of Patent: February 8, 2000
    Assignee: Lockheed Martin Energy Research Corporation
    Inventors: Rodney Allen McKee, Frederick Joseph Walker
  • Patent number: 5906857
    Abstract: An apparatus, system and method for controlling parameters attending the emission of a vaporized material from a source in a HV environment utilizes at least one shutter which is rotatably mounted over an exit opening through which vaporized material must exit the source. The shutter has a closure portion and is mounted adjacent the exit opening associated with the source for rotation about an axis so that by rotating the shutter about the rotation axis, the closure portion repeatedly covers and uncovers the exit opening in an intermittent fashion to prevent the emission of a vaporized material from the source during the periods of shutter rotation during which the exit opening is covered by the closure portion and to permit the emission of a vaporized material from the source during the periods of shutter rotation during which the exit opening is uncovered by the closure portion.
    Type: Grant
    Filed: May 13, 1997
    Date of Patent: May 25, 1999
    Assignee: Ultratherm, Inc.
    Inventors: Rodney Allen McKee, Frederick Joseph Walker
  • Patent number: 5876866
    Abstract: A process and structure wherein a film comprised of a perovskite or a spinel is built epitaxially upon a surface, such as an alkaline earth oxide surface, involves the epitaxial build up of alternating constituent metal oxide planes of the perovskite or spinel. The first layer of metal oxide built upon the surface includes a metal element which provides a small cation in the crystalline structure of the perovskite or spinel, and the second layer of metal oxide built upon the surface includes a metal element which provides a large cation in the crystalline structure of the perovskite or spinel. The layering sequence involved in the film build up reduces problems which would otherwise result from the interfacial electrostatics at the first atomic layers, and these oxides can be stabilized as commensurate thin films at a unit cell thickness or grown with high crystal quality to thicknesses of 0.5-0.7 .mu.m for optical device applications.
    Type: Grant
    Filed: August 21, 1995
    Date of Patent: March 2, 1999
    Assignee: Martin Marietta Energy Systems, Inc.
    Inventors: Rodney Allen McKee, Frederick Joseph Walker
  • Patent number: 5856033
    Abstract: A process and structure wherein a film comprised of a perovskite or a spinel is built epitaxially upon a surface, such as an alkaline earth oxide surface, involves the epitaxial build up of alternating constituent metal oxide planes of the perovskite or spinel. The first layer of metal oxide built upon the surface includes a metal element which provides a small cation in the crystalline structure of the perovskite or spinel, and the second layer of metal oxide built upon the surface includes a metal element which provides a large cation in the crystalline structure of the perovskite or spinel. The layering sequence involved in the film build up reduces problems which would otherwise result from the interfacial electrostatics at the first atomic layers, and these oxides can be stabilized as commensurate thin films at a unit cell thickness or grown with high crystal quality to thicknesses of 0.5-0.7 .mu.m for optical device applications.
    Type: Grant
    Filed: August 21, 1995
    Date of Patent: January 5, 1999
    Assignee: Martin Marietta Energy Systems, Inc.
    Inventors: Rodney Allen McKee, Frederick Joseph Walker
  • Patent number: 5846667
    Abstract: A process and structure wherein optical quality perovskites, such as BaTiO.sub.3 or SrTiO.sub.3, are grown upon a single crystal MgO substrate involves the epitaxial build up of alternating planes of TiO.sub.2 and metal oxide wherein the first plane grown upon the MgO substrate is a plane of TiO.sub.2. The layering sequence involved in the film build up reduces problems which would otherwise result from the interfacial electrostatics at the first atomic layers, and these oxides can be stabilized as commensurate thin films at a unit cell thickness or grown with high crystal quality to thicknesses of 0.5-0.7 .mu.m for optical device applications.
    Type: Grant
    Filed: July 29, 1996
    Date of Patent: December 8, 1998
    Assignee: Lockheed Martin Energy Systems, Inc.
    Inventors: Rodney Allen McKee, Frederick Joseph Walker
  • Patent number: 5830270
    Abstract: A structure including a film of a desired perovskite oxide which overlies and is fully commensurate with the material surface of a semiconductor-based substrate and an associated process for constructing the structure involves the build up of an interfacial template film of perovskite between the material surface and the desired perovskite film. The lattice parameters of the material surface and the perovskite of the template film are taken into account so that during the growth of the perovskite template film upon the material surface, the orientation of the perovskite of the template is rotated 45.degree. with respect to the orientation of the underlying material surface and thereby effects a transition in the lattice structure from fcc (of the semiconductor-based material) to the simple cubic lattice structure of perovskite while the fully commensurate periodicity between the perovskite template film and the underlying material surface is maintained.
    Type: Grant
    Filed: August 5, 1996
    Date of Patent: November 3, 1998
    Assignee: Lockheed Martin Energy Systems, Inc.
    Inventors: Rodney Allen McKee, Frederick Joseph Walker
  • Patent number: 5821199
    Abstract: A process and structure wherein a film comprised of a perovskite or a spinel is built epitaxially upon a surface, such as an alkaline earth oxide surface, involves the epitaxial build up of alternating constituent metal oxide planes of the perovskite or spinel. The first layer of metal oxide built upon the surface includes a metal element which provides a small cation in the crystalline structure of the perovskite or spinel, and the second layer of metal oxide built upon the surface includes a metal element which provides a large cation in the crystalline structure of the perovskite or spinel. The layering sequence involved in the film build up reduces problems which would otherwise result from the interfacial electrostatics at the first atomic layers, and these oxides can be stabilized as commensurate thin films at a unit cell thickness or grown with high crystal quality to thicknesses of 0.5-0.7 .mu.m for optical device applications.
    Type: Grant
    Filed: August 21, 1995
    Date of Patent: October 13, 1998
    Assignee: Lockheed Martin Energy Systems, Inc.
    Inventors: Rodney Allen McKee, Frederick Joseph Walker
  • Patent number: 5804323
    Abstract: A process and structure wherein a film comprised of a perovskite or a spinel is built epitaxially upon a surface, such as an alkaline earth oxide surface, involves the epitaxial build up of alternating constituent metal oxide planes of the perovskite or spinel. The first layer of metal oxide built upon the surface includes a metal element which provides a small cation in the crystalline structure of the perovskite or spinel, and the second layer of metal oxide built upon the surface includes a metal element which provides a large cation in the crystalline structure of the perovskite or spinel. The layering sequence involved in the film build up reduces problems which would otherwise result from the interfacial electrostatics at the first atomic layers, and these oxides can be stabilized as commensurate thin films at a unit cell thickness or grown with high crystal quality to thicknesses of 0.5-0.7 .mu.m for optical device applications.
    Type: Grant
    Filed: August 21, 1995
    Date of Patent: September 8, 1998
    Assignee: Lockheed Martin Energy Systems, Inc.
    Inventors: Rodney Allen McKee, Frederick Joseph Walker
  • Patent number: 5693140
    Abstract: A process and structure wherein optical quality perovskites, such as BaTiO.sub.3 or SrTiO.sub.3, are grown upon a single crystal MgO substrate involves the epitaxial build up of alternating planes of TiO.sub.2 and metal oxide wherein the first plane grown upon the MgO substrate is a plane of TiO.sub.2. The layering sequence involved in the film build up reduces problems which would otherwise result from the interfacial electrostatics at the first atomic layers, and these oxides can be stabilized as commensurate thin films at a unit cell thickness or grown with high crystal quality to thicknesses of 0.5-0.7 .mu.m for optical device applications.
    Type: Grant
    Filed: September 18, 1995
    Date of Patent: December 2, 1997
    Assignee: Lockheed Martin Energy Systems, Inc.
    Inventors: Rodney Allen McKee, Frederick Joseph Walker