Patents by Inventor Koji Izumome

Koji Izumome 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: 7374955
    Abstract: The present invention provides a method of manufacturing a silicon wafer where a defect does not exist at a wafer surface layer part on which a device is formed, without affecting productivity and production costs of the wafer. An ingot of a silicon single crystal is grown by way of Czochralski single crystal pulling method, this silicon single crystal ingot is sliced to produce a wafer, then a surface layer of the wafer is annealed for between 0.01 microseconds and 10 seconds (inclusive) by means of a laser spike annealing apparatus such that a temperature of a wafer surface layer part is between 1250° C. and 1400° C. (inclusive).
    Type: Grant
    Filed: September 11, 2006
    Date of Patent: May 20, 2008
    Assignee: Covalent Materials Corporation
    Inventor: Koji Izumome
  • Patent number: 7226513
    Abstract: This invention provides a cleaning method of silicon wafer for obtaining a silicon wafer in which micro roughness thereof under spatial frequency of 20/?m is 0.3 to 1.5 nm3 in terms of power spectrum density, by passing a process of oxidizing the silicon wafer with ozonized water and a process of cleaning said oxidized silicon wafer with hydrofluoric acid. Consequently, it is possible to remove surface adhering pollutant such as particles and metallic foreign matter with the surface structure of silicon wafer flattened up to atomic level by annealing maintained.
    Type: Grant
    Filed: August 22, 2003
    Date of Patent: June 5, 2007
    Assignee: Toshiba Ceramics Co., Ltd.
    Inventors: Hisatsugu Kurita, Manabu Hirasawa, Hiromi Nagahama, Koji Izumome, Takao Ino, Jyunsei Yamabe, Naoya Hayamizu, Naoaki Sakurai
  • Publication number: 20070059904
    Abstract: The present invention provides a method of manufacturing a silicon wafer where a defect does not exist at a wafer surface layer part on which a device is formed, without affecting productivity and production costs of the wafer. An ingot of a silicon single crystal is grown by way of Czochralski single crystal pulling method, this silicon single crystal ingot is sliced to produce a wafer, then a surface layer of the wafer is annealed for between 0.01 microseconds and 10 seconds (inclusive) by means of a laser spike annealing apparatus such that a temperature of a wafer surface layer part is between 1250° C. and 1400° C. (inclusive).
    Type: Application
    Filed: September 11, 2006
    Publication date: March 15, 2007
    Inventor: Koji Izumome
  • Publication number: 20040045580
    Abstract: This invention provides a cleaning method of silicon wafer for obtaining a silicon wafer in which micro roughness thereof under spatial frequency of 20/&mgr;m is 0.3 to 1.5 nm3 in terms of power spectrum density, by passing a process of oxidizing the silicon wafer with ozonized water and a process of cleaning said oxidized silicon wafer with hydrofluoric acid. Consequently, it is possible to remove surface adhering pollutant such as particles and metallic foreign matter with the surface structure of silicon wafer flattened up to atomic level by annealing maintained.
    Type: Application
    Filed: August 22, 2003
    Publication date: March 11, 2004
    Applicant: TOSHIBA CERAMICS CO.,LTD.
    Inventors: Hisatsugu Kurita, Manabu Hirasawa, Hiromi Nagahama, Koji Izumome, Takao Ino, Jyunsei Yamabe, Naoya Hayamizu, Naoaki Sakurai