Patents by Inventor Takashi IZEKI

Takashi IZEKI 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).

  • Publication number: 20240003044
    Abstract: There is provided a growing method of monocrystalline silicon including: pulling up monocrystalline silicon from a dopant-added melt in which a dopant is added to a silicon melt and growing the monocrystalline silicon according to Czochralski process, in which the monocrystalline silicon is grown by calculating a critical CV value, which is a product of a dopant concentration C and a pull-up speed V at a point of time when an abnormal growth occurred in the monocrystalline silicon; and controlling at least one of the dopant concentration C or the pull-up speed V to make a CV value, which is a product of the dopant concentration C and the pull-up speed V at the point of time, below the critical CV value.
    Type: Application
    Filed: December 2, 2021
    Publication date: January 4, 2024
    Applicant: SUMCO CORPORATION
    Inventors: Takashi IZEKI, Yasuhito NARUSHIMA
  • Publication number: 20230031070
    Abstract: A monocrystalline silicon includes a shoulder, a straight body, and a tail. The straight body includes: a first straight body having a first diameter d1; and a second straight body provided closer to the shoulder than the first straight body is and having a second diameter d2 larger than the first diameter d1 by from 3.5% to 15%. Firstly, a resistivity at a start point of the straight body connected to the shoulder is set to a first resistivity. Subsequently, the monocrystalline silicon is pulled up and grown to form the first straight body, and a resistivity at a start point of the first straight body is set to a second resistivity lower than the first resistivity.
    Type: Application
    Filed: December 21, 2020
    Publication date: February 2, 2023
    Applicant: SUMCO CORPORATION
    Inventors: Takashi IZEKI, Yasuhito NARUSHIMA