Patents by Inventor Takaaki Aoshima

Takaaki Aoshima 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).

  • Nitrogen-doped silicon substantially free of oxidation induced stacking faults
    Patent number: 7404856
    Abstract: The present invention relates to a process for forming single crystal silicon ingots or wafers that contain an axially symmetric region in which vacancies are the predominant intrinsic point defect, that are substantially free of oxidation induced stacking faults, and are nitrogen doped to stabilize oxygen precipitation nuclei therein.
    Type: Grant
    Filed: January 15, 2007
    Date of Patent: July 29, 2008
    Assignee: MEMC Electronic Materials, Inc.
    Inventors: Hiroyo Haga, Takaaki Aoshima, Mohsen Banan
  • NITROGEN-DOPED SILICON SUBSTANTIALLY FREE OF OXIDATION INDUCED STACKING FAULTS
    Publication number: 20070169683
    Abstract: The present invention relates to a process for forming single crystal silicon ingots or wafers that contain an axially symmetric region in which vacancies are the predominant intrinsic point defect, that are substantially free of oxidation induced stacking faults, and are nitrogen doped to stabilize oxygen precipitation nuclei therein.
    Type: Application
    Filed: January 15, 2007
    Publication date: July 26, 2007
    Applicant: MEMC ELECTRONIC MATERIALS, INC.
    Inventors: Hiroyo Haga, Takaaki Aoshima, Mohsen Banan
  • Nitrogen-doped silicon substantially free of oxidation induced stacking faults
    Patent number: 7182809
    Abstract: A single crystal silicon, ingot or wafer form, which contains an axially symmetric region in which vacancies are the predominant intrinsic point defect, is substantially free of oxidation induced stacking faults and is nitrogen doped to stabilize oxygen precipitation nuclei therein, and a process for the preparation thereof.
    Type: Grant
    Filed: August 30, 2001
    Date of Patent: February 27, 2007
    Assignee: MEMC Electronic Materials, Inc.
    Inventors: Hiroyo Haga, Takaaki Aoshima, Mohsen Banan
  • Nitrogen-doped silicon substantially free of oxidation induced stacking faults
    Publication number: 20040009111
    Abstract: The present invention relates to single crystal silicon, ingot or wafer form, which contains an axially symmetric region in which vacancies are the predominant intrinsic point defect, is substantially free of oxidation induced stacking faults and is nitrogen doped to stabilize oxygen precipitation nuclei therein, and a process for the preparation thereof.
    Type: Application
    Filed: July 30, 2003
    Publication date: January 15, 2004
    Inventors: Hiroyo Haga, Takaaki Aoshima, Mohsen Banan
  • Method of heat treatment of wafers
    Patent number: 4016006
    Abstract: In a method of heat-treating a number of wafers each of which consists of a substance of poor heat conduction and a semiconductor layer formed on one surface of the substance, a method of heat treatment of wafers characterized in that the heat treatment is carried out under the state under which an auxiliary wafer made of a substance of good heat conduction is held in proximity to the other surface of the substance of poor heat conduction, whereby the wafers for the heat treatment are prevented from being cracked and have the characteristics made uniform.
    Type: Grant
    Filed: March 16, 1976
    Date of Patent: April 5, 1977
    Assignee: Hitachi, Ltd.
    Inventors: Akira Yoshinaka, Takaaki Aoshima, Yoshimitsu Sugita