Patents by Inventor Kouichi Inokoshi

Kouichi Inokoshi 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: 6592662
    Abstract: In a method manufacturing a silicon single crystal 8 according to an MCZ method, a flow rate of an inert gas flowing in a growth furnace 1 during growth of the silicon single crystal 8 and/or a pressure in the growth furnace 1 is altered according to a pulling amount of the silicon single crystal 8 to adjust an interstitial oxygen concentration therein. By altering a flow rate of an inert gas flowing in the growth furnace or a pressure therein, an amount of oxygen evaporating as an oxide from a surface of a silicon melt 10 in the vicinity of a crystal growth interface can be easily adjusted, and thereby, an oxygen amount included in the silicon melt 10 can be controlled with ease.
    Type: Grant
    Filed: October 24, 2001
    Date of Patent: July 15, 2003
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Izumi Fusegawa, Ryoji Hoshi, Kouichi Inokoshi, Tomohiko Ohta
  • Publication number: 20020157600
    Abstract: In a method manufacturing a silicon single crystal 8 according to an MCZ method, a flow rate of an inert gas flowing in a growth furnace 1 during growth of the silicon single crystal 8 and/or a pressure in the growth furnace 1 is altered according to a pulling amount of the silicon single crystal 8 to adjust an interstitial oxygen concentration therein. By altering a flow rate of an inert gas flowing in the growth furnace or a pressure therein, an amount of oxygen evaporating as an oxide from a surface of a silicon melt 10 in the vicinity of a crystal growth interface can be easily adjusted, and thereby, an oxygen amount included in the silicon melt 10 can be controlled with ease.
    Type: Application
    Filed: October 24, 2001
    Publication date: October 31, 2002
    Inventors: Izumi Fusegawa, Ryoji Hoshi, Kouichi Inokoshi, Tomohiko Ohta
  • Patent number: 6156119
    Abstract: In a method for producing a silicon single crystal of high quality, the silicon single crystal is grown based on a magnetic field applied Czochralski method. The single crystal is grown at a high growth rate satisfying the equation Vave.gtoreq.120/r, where Vave denotes an average crystal growth rate, and r denotes a radius of the single crystal, and a rotation number R of the single crystal in growing satisfies the equation R.ltoreq.1250/r. Oxygen concentration in-plane distribution is 10% or less, and a deformation ratio of a constant diameter portion in the silicon single crystal in a direction perpendicular to a crystal growth axis direction is 5% or less. The silicon single crystal has a high uniformity of oxygen concentration in-plane distribution without deformation of crystal, even if the crystal is grown at a growth rate exceeding the upper limits found in conventional techniques.
    Type: Grant
    Filed: March 17, 1999
    Date of Patent: December 5, 2000
    Assignee: Shin-etsu Handotai Co., Ltd.
    Inventors: Ryoji Hoshi, Kouichi Inokoshi, Tomohiko Ohta