Patents by Inventor Koji Tsuzukihashi

Koji Tsuzukihashi 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: 9388507
    Abstract: A method for manufacturing a polycrystalline silicon ingot includes unidirectionally solidifying a molten silicon upwardly from the bottom of a crucible, wherein the crucible is provided with silica deposited on the bottom of the crusible; and then dividing the degree of solidification in the crucible into a first zone from 0 mm to X in height (10 mm?X<30 mm), a second zone from X to Y in height (30 mm?Y<100 mm) and a third zone of Y or more in height, based on the bottom of the crucible, wherein a solidification rate V1 in the first zone is set in the range of 10 mm/h?V1?20 mm/h and a solidification rate V2 in the second zone is set in the range of 1 mm/h?V2?5 mm/h.
    Type: Grant
    Filed: March 25, 2011
    Date of Patent: July 12, 2016
    Assignees: MITSUBISHI MATERIALS CORPORATION, MITSUBISHI MATERIALS ELECTRONIC CHEMICALS CO., LTD.
    Inventors: Koji Tsuzukihashi, Hiroshi Ikeda, Masahiro Kanai, Saburo Wakita
  • Publication number: 20130122278
    Abstract: A polycrystalline silicon ingot manufacturing apparatus, a polycrystalline silicon ingot manufacturing method, and a polycrystalline silicon ingot are provided. The apparatus comprises: a crucible having a rectangular shape in a cross-section; an upper heater provided above the crucible; and a lower heater provided below the crucible. A silicon melt stored in the crucible is solidified from a bottom surface of the crucible upward unidirectionally. The apparatus further comprises an auxiliary heater that heats at least a bottom-surface-side portion of a sidewall of the crucible. The production yield can be improved by using the apparatus and by reducing the oxygen concentration at the location where the oxygen concentration tends to be high locally at the bottom part of the ingot.
    Type: Application
    Filed: July 21, 2011
    Publication date: May 16, 2013
    Applicants: MITSUBISHI MATERIALS ELECTRONIC CHEMICALS CO LTD, MITSUBISHI MATERIALS CORPORATION
    Inventors: Koji Tsuzukihashi, Saburo Wakita, Hiroshi Ikeda, Masahiro Kanai
  • Publication number: 20130028825
    Abstract: A method for manufacturing a polycrystalline silicon ingot includes: solidifying a silicon melt retained in a crucible unidirectionally upward from a bottom surface of the silicon melt, wherein a silicon nitride coating layer is formed on inner surfaces of side walls and an inner side surface of a bottom of the crucible, a solidification process in the crucible is divided into a first region from 0 mm to X (10 mm?X<30 mm) in hight, a second region from X to Y (30 mm?Y<100 mm), and a third region of the Y or higher, with the bottom of the crucible as a datum, a solidification rate V1 in the first region is in a range of 10 mm/h?V1?20 mm/h, and a solidification rate V2 in the second region is in a range of 1 mm/h?V2?5 mm/h.
    Type: Application
    Filed: March 25, 2011
    Publication date: January 31, 2013
    Applicants: MITSUBISHI MATERIALS ELECTRONIC CHEMICALS CO., LTD, MITSUBISHI MATERIALS CORPORATION
    Inventors: Koji Tsuzukihashi, Hiroshi Ikeda, Masahiro Kanai, Saburo Wakita
  • Publication number: 20130015318
    Abstract: Provided are a layered crucible for casting a silicon ingot that can suppress dissolution of oxygen into the silicon ingot and a method of producing the same crucible. The layered crucible for casting a silicon ingot is used in the production of a silicon ingot by melting and casting a silicon raw material. The layered crucible comprising: a silica layer provided on the inner side of a mold; and a barium coating layer provided on the surface of the silica layer.
    Type: Application
    Filed: March 28, 2011
    Publication date: January 17, 2013
    Applicants: Mitsubishi Materials Electronic Chemicals Co., Ltd., Mitsubishi Materials Corporation
    Inventors: Saburo Wakita, Koji Tsuzukihashi, Hiroshi Ikeda, Masahiro Kanai
  • Publication number: 20130008371
    Abstract: A method for manufacturing a polycrystalline silicon ingot includes unidirectionally solidifying a molten silicon upwardly from the bottom of a crucible, wherein the crucible is provided with silica deposited on the bottom of the crusible; and then dividing the degree of solidification in the crucible into a first zone from 0 mm to X in height (10 mm?X<30 mm), a second zone from X to Y in height (30 min?Y<100 mm) and a third zone of Y or more in height, based on the bottom of the crucible, wherein a solidification rate V1 in the first zone is set in the range of 10 mm/h?V1?20 mm/h and a solidification rate V2 in the second zone is set in the range of 1 mm/h?V2?5 mm/h.
    Type: Application
    Filed: March 25, 2011
    Publication date: January 10, 2013
    Applicants: Mitsubishi Materials Electronic Chemicals Co., Ltd., Mitsubishi Materials Corporation
    Inventors: Koji Tsuzukihashi, Hiroshi Ikeda, Masahiro Kanai, Saburo Wakita