Patents by Inventor Kazuhisa TORIGOE

Kazuhisa TORIGOE 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: 10861990
    Abstract: A method of manufacturing an epitaxial silicon wafer that includes growing a silicon single crystal ingot doped with a boron concentration of 2.7×1017 atoms/cm3 or more and 1.3×1019 atoms/cm3 or less by the CZ method; producing a silicon substrate by processing the silicon single crystal ingot; and forming an epitaxial layer on a surface of the silicon substrate. During growing of the silicon single crystal ingot, the pull-up conditions of the silicon single crystal ingot are controlled so that the boron concentration Y (atoms/cm3) and an initial oxygen concentration X (×1017 atoms/cm3) satisfy the expression X??4.3×10?19Y+16.3.
    Type: Grant
    Filed: September 26, 2019
    Date of Patent: December 8, 2020
    Assignee: SUMCO CORPORATION
    Inventors: Kazuhisa Torigoe, Toshiaki Ono
  • Publication number: 20200105542
    Abstract: Provided is a method of accurately predicting the thermal donor formation behavior in a silicon wafer, a method of evaluating a silicon wafer using the prediction method, and a method of producing a silicon wafer using the evaluation method. The method of predicting the formation behavior of thermal donors, includes: a first step of setting an initial oxygen concentration condition before performing heat treatment on the silicon wafer for reaction rate equations based on both a bond-dissociation model of oxygen clusters associated with the diffusion of interstitial oxygen and a bonding model of oxygen clusters associated with the diffusion of oxygen dimers; a second step of calculating the formation rate of oxygen clusters formed through the heat treatment using the reaction rate equations; and a third step of calculating the formation rate of thermal donors formed through the heat treatment based on the formation rate of the oxygen clusters.
    Type: Application
    Filed: June 12, 2018
    Publication date: April 2, 2020
    Applicant: SUMCO Corporation
    Inventors: Kazuhisa Torigoe, Shigeru Umeno, Toshiaki Ono
  • Publication number: 20200051817
    Abstract: A manufacturing method of an epitaxial silicon wafer includes: an epitaxial-film formation step for forming an epitaxial film made of silicon on a surface of a silicon wafer in a trichlorosilane gas atmosphere; and a nitrogen-concentration setting step for setting the nitrogen concentration of the surface of the epitaxial film through inward diffusion from a nitride film on the epitaxial film, the nitride film being formed by subjecting the silicon wafer provided with the epitaxial film through the epitaxial-film formation step to a heat treatment in a nitrogen atmosphere.
    Type: Application
    Filed: September 12, 2017
    Publication date: February 13, 2020
    Applicant: SUMCO CORPORATION
    Inventors: Kazuya KODANI, Toshiaki ONO, Kazuhisa TORIGOE
  • Publication number: 20200020817
    Abstract: A method of manufacturing an epitaxial silicon wafer that includes growing a silicon single crystal ingot doped with a boron concentration of 2.7×1017 atoms/cm3 or more and 1.3×1019 atoms/cm3 or less by the CZ method; producing a silicon substrate by processing the silicon single crystal ingot; and forming an epitaxial layer on a surface of the silicon substrate. During growing of the silicon single crystal ingot, the pull-up conditions of the silicon single crystal ingot are controlled so that the boron concentration Y (atoms/cm3) and an initial oxygen concentration X (×1017 atoms/cm3) satisfy the expression X??4.3×10?19Y+16.3.
    Type: Application
    Filed: September 26, 2019
    Publication date: January 16, 2020
    Applicant: SUMCO CORPORATION
    Inventors: Kazuhisa TORIGOE, Toshiaki ONO
  • Publication number: 20180204960
    Abstract: An epitaxial silicon wafer is provided with a boron-doped silicon substrate and an epitaxial layer formed on a surface of the silicon substrate, wherein the boron concentration in the silicon substrate is 2.7×1017 atoms/cm3 or more and 1.3×1019 atoms/cm3 or less, and an initial oxygen concentration in the silicon substrate is 11×1017 atoms/cm3 or less. When an oxygen precipitate evaluation heat treatment, such as a heat treatment at 700° C. for 3 hours and a heat treatment at 1,000° C. for 16 hours is executed on the epitaxial silicon wafer, the density of oxygen precipitate in the silicon substrate is 1×1010/cm3 or less.
    Type: Application
    Filed: July 6, 2016
    Publication date: July 19, 2018
    Applicant: SUMCO CORPORATION
    Inventors: Kazuhisa TORIGOE, Toshiaki ONO
  • Patent number: 9818609
    Abstract: A manufacturing method of an epitaxial silicon wafer including a silicon wafer doped with boron and having a resistivity of 100 m?·cm or less and an epitaxial film formed on the silicon wafer includes: growing the epitaxial film on the silicon wafer; and applying a heat treatment on the epitaxial silicon wafer at a temperature of less than 900 degrees C.
    Type: Grant
    Filed: December 19, 2014
    Date of Patent: November 14, 2017
    Assignee: SUMCO CORPORATION
    Inventors: Kazuhisa Torigoe, Toshiaki Ono
  • Publication number: 20170011918
    Abstract: A manufacturing method of an epitaxial silicon wafer including a silicon wafer doped with boron and having a resistivity of 100 m?•cm or less and an epitaxial film formed on the silicon wafer includes: growing the epitaxial film on the silicon wafer; and applying a heat treatment on the epitaxial silicon wafer at a temperature of less than 900 degrees C.
    Type: Application
    Filed: December 19, 2014
    Publication date: January 12, 2017
    Applicant: SUMCO CORPORATION
    Inventors: Kazuhisa TORIGOE, Toshiaki ONO
  • Patent number: 9281216
    Abstract: A manufacturing method of an epitaxial silicon wafer includes: an epitaxial-film-growth step in which an epitaxial film is grown on a silicon wafer in a reaction container, and a temperature reduction step in which a temperature of the epitaxial silicon wafer is reduced from a temperature at which the epitaxial film is grown. In the temperature reduction step, a temperature reduction rate of the epitaxial silicon wafer is controlled to satisfy a relationship represented by R?2.0×10-4X?2.9, where X (?·cm) represents a resistivity of the silicon wafer, and R (degrees C./min) represents the temperature reduction rate for lowing the temperature of the epitaxial silicon wafer from 500 degrees C. to 400 degrees C.
    Type: Grant
    Filed: June 30, 2015
    Date of Patent: March 8, 2016
    Assignee: SUMCO CORPORATION
    Inventors: Kazuhisa Torigoe, Toshiaki Ono
  • Publication number: 20160035583
    Abstract: A manufacturing method of an epitaxial silicon wafer includes: an epitaxial-film-growth step in which an epitaxial film is grown on a silicon wafer in a reaction container, and a temperature reduction step in which a temperature of the epitaxial silicon wafer is reduced from a temperature at which the epitaxial film is grown. In the temperature reduction step, a temperature reduction rate of the epitaxial silicon wafer is controlled to satisfy a relationship represented by R?2.0×10-4X?2.9, where X (?·cm) represents a resistivity of the silicon wafer, and R (degrees C./min) represents the temperature reduction rate for lowing the temperature of the epitaxial silicon wafer from 500 degrees C. to 400 degrees C.
    Type: Application
    Filed: June 30, 2015
    Publication date: February 4, 2016
    Applicant: SUMCO CORPORATION
    Inventors: Kazuhisa TORIGOE, Toshiaki ONO