Patents by Inventor Hidetoshi Kurogi

Hidetoshi Kurogi 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: 7374614
    Abstract: The method for manufacturing a single crystal semiconductor achieves an object to reduce the impurity concentration nonuniformity within a semiconductor wafer plane and thus to improve the wafer planarity by introducing an impurity into the single crystal semiconductor more uniformly during the pulling of the single crystal semiconductor from a melt. In the course of pulling the single crystal semiconductor (6), the rotating velocity (?2) of the single crystal semiconductor (6) being pulled is adjusted to a predetermined value or higher, and a magnetic field having a strength in a predetermined range is applied to the melt (5). Particularly, the crystal peripheral velocity is adjusted to 0.126 m/sec or higher, and M/V1/3 is adjusted to 35.5?M/V1/3?61.3. More desirably, the crystal peripheral velocity is adjusted to 0.141 m/sec or higher, and M/V1/3 is adjusted to 40.3?M/V1/3?56.4.
    Type: Grant
    Filed: February 18, 2005
    Date of Patent: May 20, 2008
    Assignee: Komatsu Denshi Kinzoku Kabushiki Kaisha
    Inventors: Masafumi Ura, Hidetoshi Kurogi, Toshiharu Yubitani, Noboru Furuichi
  • Publication number: 20070131158
    Abstract: The method for manufacturing a single crystal semiconductor achieves an object to reduce the impurity concentration nonuniformity within a semiconductor wafer plane and thus to improve the wafer planarity by introducing an impurity into the single crystal semiconductor more uniformly during the pulling of the single crystal semiconductor from a melt. In the course of pulling the single crystal semiconductor (6), the rotating velocity (?2) of the single crystal semiconductor (6) being pulled is adjusted to a predetermined value or higher, and a magnetic field having a strength in a predetermined range is applied to the melt (5). Particularly, the crystal peripheral velocity is adjusted to 0.126 m/sec or higher, and M/V1/3 is adjusted to 35.5?M/V1/3?61.3. More desirably, the crystal peripheral velocity is adjusted to 0.141 m/sec or higher, and M/V1/3 is adjusted to 40.3?M/V1/3?56.4.
    Type: Application
    Filed: February 18, 2005
    Publication date: June 14, 2007
    Applicant: KOMATSU DENSHI KINZOKU KABUSHIKI KAISHA
    Inventors: Masafumi Ura, Hidetoshi Kurogi, Toshiharu Yubitani, Noboru Furuichi
  • Patent number: 6139630
    Abstract: A suspender for suspending polycrystalline rods steadfastly and easily in a furnace for single-crystal fabrication by the recharge or additionally charged method is disclosed. The suspender includes a plate which is made of molybdenum or SiC-coated graphite and a stick perpendicularly connected to the center of the plate. Both sides of the openings are arms for supporting the polycrystalline rods, thereby suspending the polycrystalline rods vertically in the opening. Means for preventing the polycrystalline rods from slipping out of the suspender are provided at ends of the arms. Therefore, the polycrystalline rods will not slip from the opening even though the plate is inclined. The suspender is suspended in the furnace by a stick. The polycrystalline rods require few tasks to form grooves and install on the suspender, thus decreasing the process time and manufacturing cost.
    Type: Grant
    Filed: May 16, 1996
    Date of Patent: October 31, 2000
    Assignee: Komatsu Electronic Metals Co., Ltd.
    Inventors: Tatsuhiro Fujiyama, Hiroshi Inagaki, Teruhiko Uchiyama, Hidetoshi Kurogi
  • Patent number: 5888293
    Abstract: A low-cost and high productivity charging material is provided for use in the recharge or additional charge fabrication of single-crystal semiconductor by means of the CZ method. Common polysilicon rods utilized in recharge or additional charge fabrication have their end portions formed into ring grooves. A joint element is made of silicon. When the end portions of the rods contact, the joint element engages the grooves to connect the rods together along their longitudinal direction. The rods can have arbitrary length, whereas the total weight, including the joint element, must be adjusted by the length to be greater than those of the melted polysilicon and the suspending portions.
    Type: Grant
    Filed: December 26, 1996
    Date of Patent: March 30, 1999
    Assignee: Komatsu Electronic Metals Co., Ltd.
    Inventors: Tatsuhiro Fujiyama, Hiroshi Inagaki, Hidetoshi Kurogi