Patents by Inventor Wei-Kan Chu

Wei-Kan Chu 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: 20020006877
    Abstract: Planarizing High Temperature Superconductor (HTS) surfaces, especially HTS thin film surfaces is crucial for HTS thin film device processing. Disclosed is a method of surface planarization for HTS film. The method includes first smoothing the HTS surface by Gas Cluster Ion Beam bombardment, followed by annealing in partial pressure of oxygen to regrow the damaged surface layer. A rough HTS surface can be planarized down to a smoothness with a standard deviation of one nanometer or better.
    Type: Application
    Filed: June 25, 2001
    Publication date: January 17, 2002
    Applicant: Epion Corporation
    Inventors: Wei-Kan Chu, Judy Z. Wu
  • Patent number: 6251835
    Abstract: Planarizing High Temperature Superconductor (HTS) surfaces, especially HTS thin film surfaces is crucial for HTS thin film device processing. Disclosed is a method of surface planarization for HTS film. The method includes first smoothing the HTS surface by Gas Cluster Ion Beam bombardment, followed by annealing in partial pressure of oxygen to regrow the damaged surface layer. A rough HTS surface can be planarized down to a smoothness with a standard deviation of one nanometer or better.
    Type: Grant
    Filed: May 6, 1998
    Date of Patent: June 26, 2001
    Assignee: Epion Corporation
    Inventors: Wei-Kan Chu, Judy Z. Wu
  • Patent number: 6231011
    Abstract: A torque/reactive momentum wheel control system for use in satellites for dynamic attitude maintenance and alteration where the flywheel of each momentum wheel is levitated by a high-temperature superconducting element repulsively interacting with permanent magnets in the flywheel. The spin rate (rpm) of the flywheel being controlled by either an active magneto or electromagneto drive system. Each momentum wheel is cooled by a cryo-cooler and can have a total weight of about 10 Kg to a fraction of 1 Kg and delivering 3.5 Js with less than 1 W loss.
    Type: Grant
    Filed: November 2, 1998
    Date of Patent: May 15, 2001
    Assignee: University of Houston System
    Inventors: Wei-Kan Chu, Ki Bui Ma, Jang-Horng Yu, Quark Yung-Sung Chen, Eujeong Lee, Yevgeniy Postrekhin
  • Patent number: 5947237
    Abstract: Disclosed are devices for influencing and/or controlling relative motion between members, such as vibration damping or absorbing devices, clutches and brakes. The devices comprise a magnet on one member and a field cooled superconductor on the other member. The devices utilize the interaction of the magnetic field of the magnet as it moves through the pinned flux in the superconductor to either influence or control relative motion.
    Type: Grant
    Filed: August 29, 1995
    Date of Patent: September 7, 1999
    Assignee: University of Houston - University Park
    Inventors: Chase K. McMichael, Ki-Bui Ma, Wei-Kan Chu
  • Patent number: 5831362
    Abstract: Disclosed is a flywheel system for storing kinetic energy which utilizes a high temperature superconductor/magnet system for the flywheel bearings. The flywheel includes a first magnet, and having a ring magnet defining an opening. The levitation system includes a magnet for attractively interacting with first flywheel magnet, with a high temperature superconductor interposed between them, and further includes a magnet system for repulsively interacting with and partially inserted into the ring magnet.
    Type: Grant
    Filed: July 16, 1997
    Date of Patent: November 3, 1998
    Assignee: The University of Houston
    Inventors: Wei-Kan Chu, Quark Yung-Sung Chen, Ki-Bui Ma, Harold Zule Xia, Mark Alan Lamb, Rodger Sheldon Cooley, Chase Kenyon McMichael
  • Patent number: 5726512
    Abstract: An isolation system for isolating a first object from vibrations from a second object. Such vibrations will have three orthogonal components, one oriented along a line between the objects, and two oriented 90.degree. apart in a plane normal to that line. The system includes three superconductor/magnet stages, each stage designed to extinguish one of the orthogonal components.
    Type: Grant
    Filed: October 4, 1996
    Date of Patent: March 10, 1998
    Assignee: The University of Houston System
    Inventors: Wei-Kan Chu, Quark Yung-Sung Chen, Ki-Bui Ma, Mark Alan Lamb, Chase Kenyon McMichael, Ignatius S. T. Tsong
  • Patent number: 5542506
    Abstract: Disclosed are devices for influencing and/or controlling relative motion between members, such as vibration damping or absorbing devices, clutches and brakes. The devices comprise a magnet on one member and a field cooled superconductor on the other member. The devices utilize the interaction of the magnetic field of the magnet as it moves through the pinned flux in the superconductor to either influence or control relative motion.
    Type: Grant
    Filed: December 3, 1991
    Date of Patent: August 6, 1996
    Assignee: University of Houston-University Park
    Inventors: Chase K. McMichael, Ki-Bui Ma, Wei-Kan Chu
  • Patent number: 5177387
    Abstract: A magnetic bearing having a rotatable member and a stationary member on one of which is mounted a superconductor while on the other is mounted a set of permanent magnets or electromagnets arranged as a quadrupole or multiple dipoles. The magnetic member, which is in the form of a dipole, a quadrupole, or other multiple dipole, such as an octopole, is positioned to enable the magnetic fields generated by the permanent magnets to interact with the superconducting material and to confine the shaft in all directions in the desired location. The bearing systems can be used as either a thrust bearing or as a journal bearing, or as both. Each dipole may be twinned to reduce magnetic field asymmetry and reduce energy dissipation upon rotation. The superconductor may be laminated, and/or additional magnets may be located outside the superconductor in order to increase the bearing stiffness and rigidity.
    Type: Grant
    Filed: December 4, 1990
    Date of Patent: January 5, 1993
    Assignee: University of Houston-University Park
    Inventors: Chase K. McMichael, Wei-Kan Chu
  • Patent number: 5159219
    Abstract: A superconductor-magnet system having high thrust and stability, with a method for increasing the thrust and stability of such a system, comprises a first magnet, a second magnet and a superconductor. The magnets are in motion relative to each other and the superconductor is in motion relative to one and stationary relative to the other magnet. High thrust and stability can be achieved by increasing the magnetic field of the magnet in motion relative to the superconductor. Also disclosed are magnetic thrust and journal bearings utilizing the above system.
    Type: Grant
    Filed: May 16, 1991
    Date of Patent: October 27, 1992
    Assignee: University of Houston-University Park
    Inventors: Wei-Kan Chu, Ki-Bui Ma, Chase K. McMichael
  • Patent number: 5068020
    Abstract: Disclosed herein is a coated substrate and a process for forming films on substrates and for providing a particularly smooth film on a substrate. The method of this invention involves subjecting a surface of a substrate to contact with a stream of ions of an inert gas having sufficient force and energy to substantially change the surface characteristics of said substrate, and then exposing a film-forming material to a stream of ions of an inert gas having sufficient energy to vaporize the atoms of said film-forming material and to transmit the vaporized atoms to the substrate surface with sufficient force to form a film bonded to the substrate. This process is particularly useful commercially because it forms strong bonds at room temperature.This invention is particularly useful for adhering a gold film to diamond and forming ohmic electrodes on diamond, but also can be used to bond other films to substrates.
    Type: Grant
    Filed: July 10, 1989
    Date of Patent: November 26, 1991
    Assignee: The University of North Carolina at Chapel Hill
    Inventors: Wei-kan Chu, Charles B. Childs
  • Patent number: 4956000
    Abstract: A method for fabricating a lens in which the lens composition is controlled by dynamic shaping and shadowing. A lens material is vaporized and directed to a substrate through an orifice which is rotating relative to the substrate about the lens axis and which has a non-uniform radial distribution. The lens material is condensed on the substrate to form a lens having a radially non-uniform but axially symmetrical distribution. Thereafter, the original orifice may be replaced by a complimentary orifice and another lens material vaporized and directed to the substrate through the replacement orifice which is also rotating relative to the substrate about the lens axis and which also has a non-uniform radial distribution. This second lens material condenses on the first condensed lens material to form a compound lens.
    Type: Grant
    Filed: June 28, 1989
    Date of Patent: September 11, 1990
    Inventors: Robert R. Reeber, Wei-Kan Chu, Salah M. Bedair
  • Patent number: 4891329
    Abstract: A method of forming a nonsilicon semiconductor layer on an insulating layer by forming a thin heteroepitaxial layer of nonsilicon semiconductor on a first substrate having a lattice structure which matches that of the heteroepitaxial layer. A first insulating layer is formed on the heteroepitaxial layer. A second insulating layer is formed on the surface of a second substrate. The first and second insulating layers are bonded together to form a unified structure, and the first substate is etched away. In a preferred embodiment the heteroepitaxial layer is germanium, gallium arsenide or silicon-germanium alloy while the first substrate is silicon, germanium, gallium arsenide or silicon-germanium alloy.
    Type: Grant
    Filed: November 29, 1988
    Date of Patent: January 2, 1990
    Assignees: University of North Carolina, Microelectronics Center of North Carolina
    Inventors: Arnold Reisman, Wei-Kan Chu
  • Patent number: 4544576
    Abstract: Deep dielectric isolation zones in a substrate are achieved by forming trenches using reactive ion etching. A glass having a coefficient of thermal expansion closely matching that of the substrate is deposited onto the trench to entirely or partially fill the trench. Deposition can be by sedimentation, centrifugation or spin-on techniques. The structure is then fired until the glass particles fuse into a continuous glass layer and final smoothing if necessary can be accomplished.
    Type: Grant
    Filed: July 27, 1981
    Date of Patent: October 1, 1985
    Assignee: International Business Machines Corporation
    Inventors: Wei-Kan Chu, William A. Pliskin, Jacob Riseman
  • Patent number: 4452645
    Abstract: A transistor structure is provided with an emitter which is formed from non-monocrystalline silicon which is caused to be converted to monocrystalline silicon during the manufacture of the transistor. In the process of manufacturing the present semiconductor structure, a subcollector is formed in a semiconductor substrate. The subcollector dopant out diffuses into a subsequently deposited epitaxial layer. A base region is formed in the epitaxial layer of a conductivity type opposite that of the conductivity type of the subcollector. This results in a PN junction between the base region and the out diffused subcollector impurities forming the collector of the transistor.A layer of non-monocrystalline silicon is deposited on the epitaxial layer. At least a portion of the non-monocrystalline silicon forms a precursor for an emitter region which is contiguous to but vertically displaced from the surface of the base region.
    Type: Grant
    Filed: March 12, 1981
    Date of Patent: June 5, 1984
    Assignee: International Business Machines Corporation
    Inventors: Wei-Kan Chu, Ingrid E. Magdo, Hans S. Rupprecht
  • Patent number: 4408254
    Abstract: A capacitor is formed by placing between two electodes a thin film of amorphous titanate which has been ion implanted with noble gas ions.
    Type: Grant
    Filed: November 18, 1981
    Date of Patent: October 4, 1983
    Assignee: International Business Machines Corporation
    Inventors: Wei-Kan Chu, James K. Howard
  • Patent number: 4333808
    Abstract: A suitable substrate is provided to which is applied a metal electrically conductive film electrode. The substrate and electrically conductive electrode film are then exposed to ion beam implantation of O+ or N+ ions to impregnate the surface of the metal electrode with O+ or N+ ions. Thereafter, the substrate and electrically conductive film having implanted O+ or N+ ions is annealed so as to stabilize the oxide structure which has been implanted into the surface of the electrically conductive film to provide an ultra-thin dielectric film.
    Type: Grant
    Filed: February 13, 1981
    Date of Patent: June 8, 1982
    Assignee: International Business Machines Corporation
    Inventors: Arup Bhattacharyya, Wei-Kan Chu, James K. Howard, Francis W. Wiedman
  • Patent number: 4307132
    Abstract: Thin film structures comprising a layer of aluminum and a material having a tendency to interact with aluminum are separated by an intermediate layer of aluminum having a high aluminum oxide content. The intermediate layer prevents said interaction by acting as a diffusion barrier.Preferred embodiments are directed to silicon semiconductor metallization structures, including Schottky barrier contacts, which comprise a bottom layer of tantalum, or other transition metal, or a metal silicide in contact with a silicon substrate, an intermediate layer of aluminum having a high aluminum oxide content and a top layer of aluminum. The intermediate layer functions as a diffusion barrier between aluminum and the metal, metal silicide or silicon.
    Type: Grant
    Filed: November 7, 1979
    Date of Patent: December 22, 1981
    Assignee: International Business Machines Corp.
    Inventors: Wei-Kan Chu, James K. Howard, James F. White
  • Patent number: 4206472
    Abstract: Thin film structures comprising a layer of aluminum and a material having a tendency to interact with aluminum are separated by an intermediate layer of aluminum having a high aluminum oxide content. The intermediate layer prevents said interaction by acting as a diffusion barrier.Preferred embodiments are directed to silicon semiconductor metallization structures, including Schottky barrier contacts, which comprise a bottom layer of tantalum, or other transition metal, or a metal silicide in contact with a silicon substrate, an intermediate layer of aluminum having a high aluminum oxide content and a top layer of aluminum. The intermediate layer functions as a diffusion barrier between aluminum and the metal, metal silicide or silicon.
    Type: Grant
    Filed: December 27, 1977
    Date of Patent: June 3, 1980
    Assignee: International Business Machines Corporation
    Inventors: Wei-Kan Chu, James K. Howard, James F. White