Patents by Inventor Xuefeng Liu

Xuefeng Liu 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: 7138285
    Abstract: A method of performing quantum well intermixing in a semiconductor device structure uses a sacrificial part of a cap layer, that is removed after QWI processing, to restore the cap surface to a condition in which high performance contacts are still possible.
    Type: Grant
    Filed: May 21, 2003
    Date of Patent: November 21, 2006
    Assignee: Intense Limited
    Inventors: Stephen Najda, Stewart Duncan McDougall, Xuefeng Liu
  • Publication number: 20060186983
    Abstract: An inductor formed on an integrated circuit chip including one or more inner layers between two or more outer layers, inductor metal winding turns included in one or more inner layers, and a magnetic material forming the two or more outer layers and the one or more inner layers. In one embodiment, the magnetic material is a photoresist paste having magnetic particles. In another embodiment, the magnetic material is a series of magnetic metallic strips disposed on each of first and second portions of the two or more outer layers and on each of the one or more inner layers. The series of magnetic metallic strips on the first and second portions form a grid pattern. Other embodiments include an adjustable controlled compound deposit and control windings with adjustable electrical currents.
    Type: Application
    Filed: April 7, 2006
    Publication date: August 24, 2006
    Applicant: International Business Machines Corporation
    Inventors: Hanyi Ding, Kai Feng, Zhong-Xiang He, Xuefeng Liu
  • Publication number: 20060163688
    Abstract: A method of forming a semiconductor structure, comprising: providing a substrate having a buried insulative layer and a heavily doped layer; forming a first trench within the substrate around a protected area; filling the first trench with an insulative material, wherein the first trench filled with the insulative material and the buried insulative layer combine to form a high impedance noise isolation that surrounds the protected area on all sides except one side of the protected area to isolate noise from the protected area; forming a second trench within the substrate around the first trench; and filling the second trench with a conductive material, wherein the second trench filled with the conductive material and the heavily doped layer combine to form a low impedance ground path that surrounds the high impedance noise isolation on all sides except one side of the high impedance noise isolation to isolate noise from the protected area.
    Type: Application
    Filed: January 27, 2005
    Publication date: July 27, 2006
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Hanyi Ding, Kai Feng, Zhong-Xiang He, Xuefeng Liu
  • Publication number: 20060148106
    Abstract: A mixed-signal chip having a signal transformer located between analog circuitry and digital circuitry. The signal transformer includes a primary winding electrically coupled to the analog circuitry and a secondary winding electrically coupled to the digital circuitry. The primary and secondary windings are magnetically coupled with one another via a magnetic core. The magnetic coupling between the primary and secondary windings inhibits the coupling of electrical noise between the analog and digital circuitries.
    Type: Application
    Filed: January 6, 2005
    Publication date: July 6, 2006
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Hanyi Ding, Kai Feng, Zhong-Xiang He, Xuefeng Liu
  • Patent number: 7071530
    Abstract: A method of forming a semiconductor structure, comprising: providing a substrate having a buried insulative layer and a heavily doped layer; forming a first trench within the substrate around a protected area; filling the first trench with an insulative material, wherein the first trench filled with the insulative material and the buried insulative layer combine to form a high impedance noise isolation that surrounds the protected area on all sides except one side of the protected area to isolate noise from the protected area; forming a second trench within the substrate around the first trench; and filling the second trench with a conductive material, wherein the second trench filled with the conductive material and the heavily doped layer combine to form a low impedance ground path that surrounds the high impedance noise isolation on all sides except one side of the high impedance noise isolation to isolate noise from the protected area.
    Type: Grant
    Filed: January 27, 2005
    Date of Patent: July 4, 2006
    Assignee: International Business Machines Corporation
    Inventors: Hanyi Ding, Kai D. Feng, Zhong-Xiang He, Xuefeng Liu
  • Patent number: 7061359
    Abstract: An inductor formed on an integrated circuit chip including one or more inner layers (12) between two or more outer layers (14), inductor metal winding turns (16) included in one or more inner layers (12), and a magnetic material forming the two or more outer layers (14) and the one or more inner layers (12). In one embodiment, the magnetic material is a photoresist paste having magnetic particles. In another embodiment, the magnetic material is a series of magnetic metallic strips (32 and 36) disposed on each of the first and second portions (30 and 34, respectively) of the two or more outer layers (14) and on each of the one or more inner layers (12). The series of magnetic metallic strips on the first and second portions (30, 34) form a grid pattern. Other embodiments include an adjustable controlled compound deposit and control windings with adjustable electrical currents.
    Type: Grant
    Filed: June 30, 2003
    Date of Patent: June 13, 2006
    Assignee: International Business Machines Corporation
    Inventors: Hanyi Ding, Kai Di Feng, Zhong-Xiang He, Xuefeng Liu
  • Publication number: 20060060887
    Abstract: A heterojunction bipolar transistor is formed in a semiconductor substrate of a first conductivity type including a collector region. A base region is formed on the substrate and an emitter region is formed over the base region. At least one of the collector, base and emitter regions includes a first region doped with an impurity having a first concentration and a second region doped with the impurity having a second concentration. Noise performance and reliability of the heterojunction bipolar transistor is improved without degrading ac performance.
    Type: Application
    Filed: September 21, 2004
    Publication date: March 23, 2006
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Peter Geiss, Alvin Joseph, Rajendran Krishnasamy, Xuefeng Liu
  • Publication number: 20060057748
    Abstract: A method of performing quantum well intermixing in a semiconductor device structure uses a sacrificial part of a cap layer, that is removed after QWI processing, to restore the cap surface to a condition in which high performance contacts are still possible.
    Type: Application
    Filed: May 21, 2003
    Publication date: March 16, 2006
    Inventors: Stephen Najda, Stewart McDougall, Xuefeng Liu
  • Patent number: 6967167
    Abstract: A method for removing silicon dioxide residuals is disclosed. The method includes reacting a portion of a silicon dioxide layer (i.e., oxide) to form a reaction product layer, removing the reaction product layer and annealing in an environment to remove oxide residuals. The method finds application in a variety of semiconductor fabrication processes including, for example, fabrication of a vertical HBT or silicon-to-silicon interface without an oxide interface.
    Type: Grant
    Filed: September 30, 2003
    Date of Patent: November 22, 2005
    Assignee: International Business Machines Corporation
    Inventors: Peter J. Geiss, Alvin J. Joseph, Xuefeng Liu, James S. Nakos, James J. Quinlivan
  • Publication number: 20050070101
    Abstract: A method for removing silicon dioxide residuals is disclosed. The method includes reacting a portion of a silicon dioxide layer (i.e., oxide) to form a reaction product layer, removing the reaction product layer and annealing in an environment to remove oxide residuals. The method finds application in a variety of semiconductor fabrication processes including, for example, fabrication of a vertical HBT or silicon-to-silicon interface without an oxide interface.
    Type: Application
    Filed: September 30, 2003
    Publication date: March 31, 2005
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Peter Geiss, Alvin Joseph, Xuefeng Liu, James Nakos, James Quinlivan
  • Publication number: 20040263310
    Abstract: An inductor formed on an integrated circuit chip including one or more inner layers (12) between two or more outer layers (14), inductor metal winding turns (16) included in one or more inner layers (12), and a magnetic material forming the two or more outer layers (14) and the one or more inner layers (12). In one embodiment, the magnetic material is a photoresist paste having magnetic particles. In another embodiment, the magnetic material is a series of magnetic metallic strips (32 and 36) disposed on each of the first and second portions (30 and 34, respectively) of the two or more outer layers (14) and on each of the one or more inner layers (12). The series of magnetic metallic strips on the first and second portions (30, 34) form a grid pattern. Other embodiments include an adjustable controlled compound deposit and control windings with adjustable electrical currents.
    Type: Application
    Filed: June 30, 2003
    Publication date: December 30, 2004
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Hanyi Ding, Kai Di Feng, Zhong-Xiang He, Xuefeng Liu
  • Patent number: 6770127
    Abstract: An additive composition than can be incorporated into asphalt materials to impart thereto multigrade characteristics. The additive is prepared by reacting together at least one saponifiable organic acid, at least one resin acid, at least one unsaturated organic compound, and an alkali metal base to form a reaction product. Water produced during the reaction is removed as the reaction proceeds. The resulting reaction product can be formed into a powder and combined together with asphalt materials to produce multigrade asphalts.
    Type: Grant
    Filed: May 16, 2002
    Date of Patent: August 3, 2004
    Assignee: Shandong Heritage Highway Materials Technologies
    Inventors: Anthony J. Kriech, Herbert L. Wissel, Haifang Zhou, Xuefeng Liu, Feng Xu
  • Publication number: 20040140481
    Abstract: A high performance SiGe HBT that has a SiGe layer with a peak Ge concentration of at least approximately 20% and a boron-doped base region formed therein having a thickness. The base region includes diffusion-limiting impurities substantially throughout its thickness, at a peak concentration below that of boron in the base region. Both the base region and the diffusion-limiting impurities are positioned relative to a peak concentration of Ge in the SiGe layer so as to optimize both performance and yield.
    Type: Application
    Filed: January 7, 2004
    Publication date: July 22, 2004
    Inventors: Basanth Jagannathan, Alvin J. Joseph, Xuefeng Liu, Kathryn T. Schonenberg, Ryan W. Wuthrich
  • Patent number: 6744079
    Abstract: A high performance SiGe HBT that has a SiGe layer with a peak Ge concentration of at least approximately 20% and a boron-doped base region formed therein having a thickness. The base region includes diffusion-limiting impurities substantially throughout its thickness, at a peak concentration below that of boron in the base region. Both the base region and the diffusion-limiting impurities are positioned relative to a peak concentration of Ge in the SiGe layer so as to optimize both performance and yield.
    Type: Grant
    Filed: March 8, 2002
    Date of Patent: June 1, 2004
    Assignee: International Business Machines Corporation
    Inventors: Basanth Jagannathan, Alvin J. Joseph, Xuefeng Liu, Kathryn T. Schonenberg, Ryan W. Wuthrich
  • Patent number: 6719884
    Abstract: A method of manufacturing an optical device, wherein the device body portion from which the device is to be made includes at least one Quantum Well, the method including the step of causing an impurity material including copper to intermix with the Quantum Well.
    Type: Grant
    Filed: January 15, 2002
    Date of Patent: April 13, 2004
    Assignee: Intense Photonics Limited
    Inventors: John Haig Marsh, Craig James Hamilton, Olek Peter Kowalski, Stuart Duncan McDougall, Xuefeng Liu, Bo-Cang Qui
  • Publication number: 20030213407
    Abstract: An additive composition than can be incorporated into asphalt materials to impart thereto multigrade characteristics. The additive is prepared by reacting together at least one saponifiable organic acid, at least one resin acid, at least one unsaturated organic compound, and an alkali metal base to form a reaction product. Water produced during the reaction is removed as the reaction proceeds. The resulting reaction product can be formed into a powder and combined together with asphalt materials to produce multigrade asphalts.
    Type: Application
    Filed: May 16, 2002
    Publication date: November 20, 2003
    Inventors: Anthony J. Kriech, Herbert L. Wissel, Haifang Zhou, Xuefeng Liu, Feng Xu
  • Publication number: 20030170960
    Abstract: A high performance SiGe HBT that has a SiGe layer with a peak Ge concentration of at least approximately 20% and a boron-doped base region formed therein having a thickness. The base region includes diffusion-limiting impurities substantially throughout its thickness, at a peak concentration below that of boron in the base region. Both the base region and the diffusion-limiting impurities are positioned relative to a peak concentration of Ge in the SiGe layer so as to optimize both performance and yield.
    Type: Application
    Filed: March 8, 2002
    Publication date: September 11, 2003
    Applicant: International Business Machines Corporation
    Inventors: Basanth Jagannathan, Alvin J. Joseph, Xuefeng Liu, Kathryn T. Schonenberg, Ryan W. Wuthrich
  • Publication number: 20030053789
    Abstract: There is disclosed an improved method of manufacturing an optical device using impurity induced Quantum Well Intermixing (QWI) process.
    Type: Application
    Filed: January 15, 2002
    Publication date: March 20, 2003
    Applicant: The University Court of the University of Glasgow
    Inventors: John Haig Marsh, Craig James Hamilton, Olek Peter Kowalski, Stuart Duncan McDougall, Xuefeng Liu, Bo-Cang Qui