Patents Assigned to IIS Materials Corporation, Ltd.
  • Patent number: 7842118
    Abstract: Scrap silicon from which a profit can be obtained taking into consideration the purchase price and refining cost of scrap silicon and the expected sale price of silicon products is selectively recovered, the recovered scrap silicon is refined, and silicon which can be sold as a silicon product is manufactured.
    Type: Grant
    Filed: June 2, 2005
    Date of Patent: November 30, 2010
    Assignee: IIS Materials Corporation, Ltd.
    Inventors: Norichika Yamauchi, Takehiko Shimada
  • Patent number: 7815882
    Abstract: In a refining method for boron-containing silicon, boron-containing silicon is irradiated with an electron beam in a vacuum vessel to melt the boron-containing silicon. A boron compound-forming substance is introduced into the vacuum vessel, and boron contained in the molten silicon is formed into a boron compound. After at least a portion of the boron compound has vaporized, irradiation with the electron beam is stopped. The high-purity molten silicon can then be solidified.
    Type: Grant
    Filed: September 23, 2005
    Date of Patent: October 19, 2010
    Assignee: IIS Materials Corporation, Ltd.
    Inventors: Norichika Yamauchi, Takehiko Shimada, Masafumi Maeda
  • Patent number: 7799133
    Abstract: A crucible apparatus includes a hollow crucible body which is open at its upper and lower ends and a bottom plate which is formed separately from the crucible body and can close off the lower end of the crucible body. A space for receiving a molten material is formed by placing the crucible body atop the bottom plate. When molten material received in the space has solidified, the crucible body is raised off the bottom plate, and solidified material is pushed out of one end of the crucible body and removed from the crucible body.
    Type: Grant
    Filed: May 1, 2006
    Date of Patent: September 21, 2010
    Assignee: IIS Materials Corporation, Ltd.
    Inventors: Norichika Yamauchi, Takehiko Shimada
  • Patent number: 7687019
    Abstract: A refining apparatus for scrap silicon using an electron beam which is suitable for recycling of scrap silicon which is formed during the manufacture of silicon products such as silicon wafers includes a vacuum chamber, a crucible installed within the vacuum chamber, a hearth which is installed next to the crucible within the vacuum chamber and which receives granular scrap silicon and which melts granular silicon by irradiation with an electron beam and which supplies molten silicon to the crucible, and a raw material supply apparatus which is installed within the vacuum chamber and which stores a prescribed amount of granular scrap silicon and supplies the stored granular scrap silicon via a chute.
    Type: Grant
    Filed: June 2, 2005
    Date of Patent: March 30, 2010
    Assignee: IIS Materials Corporation, Ltd.
    Inventors: Norichika Yamauchi, Takehiko Shimada
  • Patent number: 7632329
    Abstract: A method of refining scrap silicon using an electron beam includes a step of selectively preparing lumps of n-type scrap silicon containing a specific impurity element as a dopant, a step of crushing the prepared lumps of scrap silicon, a step of placing the crushed silicon into a vacuum vessel, a step of irradiating the crushed silicon which was placed into the vacuum vessel with an electron beam to melt it and vaporize at least a portion of the impurity element, and a step of solidifying the resulting silicon.
    Type: Grant
    Filed: June 2, 2005
    Date of Patent: December 15, 2009
    Assignee: IIS Materials Corporation, Ltd.
    Inventors: Norichika Yamauchi, Takehiko Shimada
  • Patent number: 7526388
    Abstract: Non-destructive testing is performed on individual pieces of scrap silicon using an energy dispersive x-ray fluorescent analyzer to determine from the obtained spectral data whether a prescribed impurity element is contained therein. The electrical resistivity of each piece of scrap silicon can be measured, and the concentration of the impurity element contained in the scrap on can be calculated from the resistivity.
    Type: Grant
    Filed: May 16, 2006
    Date of Patent: April 28, 2009
    Assignee: IIS Materials Corporation, Ltd.
    Inventors: Norichika Yamauchi, Takehiko Shimada
  • Patent number: 7195184
    Abstract: In a method of crushing silicon blocks, a silicon block to be crushed is heated and is then forcedly cooled. Subsequently, a crushing member which contains no metal component at least on a surface thereof is made to strike the cooled silicon block to thereby crush the silicon block. Alternatively, two silicon blocks to be crushed are heated and are then forcedly cooled. Subsequently, the cooled silicon blocks are made to strike against each other, whereby the silicon blocks are crushed.
    Type: Grant
    Filed: October 1, 2004
    Date of Patent: March 27, 2007
    Assignee: IIS Materials Corporation, Ltd.
    Inventors: Norichika Yamauchi, Takehiko Shimada