Patents by Inventor Satoshi Soeta

Satoshi Soeta 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: 11028498
    Abstract: A single crystal pulling apparatus including a dopant supplying means which includes: a charging device provided outside a chamber for storing a dopant and charging the dopant into the chamber; a sublimation room provided inside the chamber for holding and sublimating the dopant charged from the charging device; a carrier gas-introducing device for introducing a carrier gas into the sublimation room; and a blowing device for blowing the dopant sublimated in the sublimation room together with the carrier gas onto a surface of a raw-material melt. The blowing device includes a tube connected to the sublimation room and blowing ports such that the sublimated dopant is scattered from the blowing ports via the tube and blown onto the surface of the raw-material melt. This provides a single crystal pulling apparatus capable of efficient doping with a sublimable dopant within the shortest possible time.
    Type: Grant
    Filed: September 19, 2017
    Date of Patent: June 8, 2021
    Assignee: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Satoshi Soeta, Kazuya Nakagawa
  • Publication number: 20200048789
    Abstract: A single crystal pulling apparatus including a dopant supplying means which includes: a charging device provided outside a chamber for storing a dopant and charging the dopant into the chamber; a sublimation room provided inside the chamber for holding and sublimating the dopant charged from the charging device; a carrier gas-introducing device for introducing a carrier gas into the sublimation room; and a blowing device for blowing the dopant sublimated in the sublimation room together with the carrier gas onto a surface of a raw-material melt. The blowing device includes a tube connected to the sublimation room and blowing ports such that the sublimated dopant is scattered from the blowing ports via the tube and blown onto the surface of the raw-material melt. This provides a single crystal pulling apparatus capable of efficient doping with a sublimable dopant within the shortest possible time.
    Type: Application
    Filed: September 19, 2017
    Publication date: February 13, 2020
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Satoshi SOETA, Kazuya NAKAGAWA
  • Patent number: 9885122
    Abstract: The invention provides a method of manufacturing an N-type silicon single crystal having a resistivity of 0.05 ?cm or less and a crystal orientation of <100> by a Czochralski method, including: bringing a seed crystal into contact with a melt doped with a dopant in a crucible; forming a cone while adjusting a taper angle ? such that a ratio of the total of individual lengths of areas each having a taper angle ? ranging from 25° to 45° to length L of a cone side surface is 20% or less, where ? being formed between a growth direction of the silicon single crystal and the cone side surface when the cone is seen in a diameter direction of the silicon single crystal; and successively forming a straight body. The method can inhibit the generation of dislocations during the cone formation without reducing the yield and productivity.
    Type: Grant
    Filed: November 11, 2013
    Date of Patent: February 6, 2018
    Assignee: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Satoshi Soeta, Shinji Nakano
  • Patent number: 9809901
    Abstract: A method for manufacturing a silicon single crystal according to a Czochralski method to manufacture an N-type silicon single crystal, including the steps of: seeding to bring a seed crystal into contact with a silicon melt in a crucible and thereafter, necking to pull the seed crystal to narrow a diameter thereof, wherein a dopant concentration in the silicon melt is predicted by a difference between a temperature at the seeding and a temperature at the necking, and resistivity of the single crystal to be pulled is controlled on the basis of the predicted dopant concentration in the silicon melt. A method for manufacturing a silicon single crystal can efficiently manufacture a silicon single crystal with a desired resistivity.
    Type: Grant
    Filed: October 16, 2014
    Date of Patent: November 7, 2017
    Assignee: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Satoshi Soeta, Shinji Nakano, Kouichi Ikeda
  • Publication number: 20160237589
    Abstract: A method for manufacturing a silicon single crystal according to a Czochralski method to manufacture an N-type silicon single crystal, including the steps of: seeding to bring a seed crystal into contact with a silicon melt in a crucible and thereafter, necking to pull the seed crystal to narrow a diameter thereof, wherein a dopant concentration in the silicon melt is predicted by a difference between a temperature at the seeding and a temperature at the necking, and resistivity of the single crystal to be pulled is controlled on the basis of the predicted dopant concentration in the silicon melt. A method for manufacturing a silicon single crystal can efficiently manufacture a silicon single crystal with a desired resistivity.
    Type: Application
    Filed: October 16, 2014
    Publication date: August 18, 2016
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Satoshi SOETA, Shinji NAKANO, Kouichi IKEDA
  • Publication number: 20150275392
    Abstract: The invention provides a method of manufacturing an N-type silicon single crystal having a resistivity of 0.05 ?cm or less and a crystal orientation of <100> by a Czochralski method, including: bringing a seed crystal into contact with a melt doped with a dopant in a crucible; forming a cone while adjusting a taper angle ? such that a ratio of the total of individual lengths of areas each having a taper angle ? ranging from 25° to 45° to length L of a cone side surface is 20% or less, where ? being formed between a growth direction of the silicon single crystal and the cone side surface when the cone is seen in a diameter direction of the silicon single crystal; and successively forming a straight body. The method can inhibit the generation of dislocations during the cone formation without reducing the yield and productivity.
    Type: Application
    Filed: November 11, 2013
    Publication date: October 1, 2015
    Inventors: Satoshi Soeta, Shinji Nakano
  • Patent number: 8652254
    Abstract: The invention is a method for pulling a silicon single crystal, which is a Czochralski method for growing the silicon single crystal by contacting a seed crystal with a melt and by pulling up, including the steps of: contacting the seed crystal with the melt; forming a necking portion under the seed crystal; and forming the silicon single crystal under the necking portion by increasing a diameter, wherein a pulling rate during forming the necking portion is 2 mm/min or less, and the silicon single crystal with the increased diameter is a boron-doped silicon single crystal having a resistivity of 1.5 m?·cm or less at a shoulder portion. Therefore, there can be provided a method of pulling a silicon single crystal without generating defects such as scratches at a wafer surface in the case of processing a boron-doped silicon single crystal ingot with a low resistivity produced by CZ method into a wafer.
    Type: Grant
    Filed: April 14, 2008
    Date of Patent: February 18, 2014
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Satoshi Soeta, Masahiro Mori
  • Patent number: 8236104
    Abstract: A single-crystal manufacturing apparatus comprising at least: a main chamber configured to accommodate a crucible; a pulling chamber continuously provided above the main chamber, the pulling chamber into which a grown single crystal is pulled and accommodated; a gas inlet provided in the pulling chamber; a gas flow-guide cylinder downwardly extending from a ceiling of the main chamber; and a heat-insulating ring upwardly extending from a lower end portion of the gas flow-guide cylinder with a diameter of the heat-insulating ring increased so as to surround an outside of the gas flow-guide cylinder, wherein at least one window is provided in a region between 50 and 200 mm from a lower end of the gas flow-guide cylinder, and an opening area of the window accounts for 50% or more of a surface area of the region between 50 and 200 mm from the lower end of the gas flow-guide cylinder.
    Type: Grant
    Filed: May 8, 2009
    Date of Patent: August 7, 2012
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Satoshi Soeta, Toshifumi Fujii
  • Publication number: 20110056427
    Abstract: A single-crystal manufacturing apparatus comprising at least: a main chamber configured to accommodate a crucible; a pulling chamber continuously provided above the main chamber, the pulling chamber into which a grown single crystal is pulled and accommodated; a gas inlet provided in the pulling chamber; a gas flow-guide cylinder downwardly extending from a ceiling of the main chamber; and a heat-insulating ring upwardly extending from a lower end portion of the gas flow-guide cylinder with a diameter of the heat-insulating ring increased so as to surround an outside of the gas flow-guide cylinder, wherein at least one window is provided in a region between 50 and 200 mm from a lower end of the gas flow-guide cylinder, and an opening area of the window accounts for 50% or more of a surface area of the region between 50 and 200 mm from the lower end of the gas flow-guide cylinder.
    Type: Application
    Filed: May 18, 2009
    Publication date: March 10, 2011
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Satoshi Soeta, Toshifumi Fujii
  • Publication number: 20100089309
    Abstract: The invention is a method for pulling a silicon single crystal, which is a Czochralski method for growing the silicon single crystal by contacting a seed crystal with a melt and by pulling up, including the steps of: contacting the seed crystal with the melt; forming a necking portion under the seed crystal; and forming the silicon single crystal under the necking portion by increasing a diameter, wherein a pulling rate during forming the necking portion is 2 mm/min or less, and the silicon single crystal with the increased diameter is a boron-doped silicon single crystal having a resistivity of 1.5 m?·cm or less at a shoulder portion. Therefore, there can be provided a method of pulling a silicon single crystal without generating defects such as scratches at a wafer surface in the case of processing a boron-doped silicon single crystal ingot with a low resistivity produced by CZ method into a wafer.
    Type: Application
    Filed: April 14, 2008
    Publication date: April 15, 2010
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Satoshi Soeta, Masahiro Mori
  • Patent number: 7258744
    Abstract: The present invention discloses a graphite heater for producing a single crystal used when producing a single crystal by the Czochralski method which comprises at least a terminal part to which electric current is supplied and a cylindrical heat generating part by resistance heating and are provided so as to surround a crucible for containing a raw material melt wherein the heat generating part has heat generating slit parts formed by being provided with upper slits extending downward from the upper end and lower slits extending upwards from the lower end by turns, and a length of at least one slit of the upper slits differs from others and/or a length of at least one slit of the lower slits differs from others so that a heat generating distribution of the heat generating part may be changed.
    Type: Grant
    Filed: December 8, 2003
    Date of Patent: August 21, 2007
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Masahiro Sakurada, Izumi Fusegawa, Satoshi Soeta, Makoto Iida
  • Publication number: 20050205004
    Abstract: The present invention discloses a graphite heater for producing a single crystal used when producing a single crystal by the Czochralski method which comprises at least a terminal part to which electric current is supplied and a cylindrical heat generating part by resistance heating and are provided so as to surround a crucible for containing a raw material melt wherein the heat generating part has heat generating slit parts formed by being provided with upper slits extending downward from the upper end and lower slits extending upwards from the lower end by turns, and a length of at least one slit of the upper slits differs from others and/or a length of at least one slit of the lower slits differs from others so that a heat generating distribution of the heat generating part may be changed.
    Type: Application
    Filed: December 8, 2003
    Publication date: September 22, 2005
    Inventors: Masahiro Sakurada, Izumi Fusegawa, Satoshi Soeta, Makoto Iida
  • Patent number: 6280522
    Abstract: There is provided a quartz glass crucible for pulling a silicon single crystal and a production process for the crucible, wherein an inner surface of the crucible is crystallized without addition of impurities during pulling a silicon single crystal, thereby impurities serving as causes of crystal defects being not incorporated into the silicon single crystal, so that deterioration of its inner surface is suppressed to improve a crystallization ratio, and accordingly productivity of the quartz glass crucible as well as a quality of the silicon single crystal is improved, and the quartz glass crucible for pulling a silicon single crystal comprises a crucible base body (3) made of a translucent quartz glass layer and a synthetic quartz glass layer (4) formed on an inner wall surface of the crucible base body (3), wherein a portion encircled by a brown ring on an inner surface of the quartz glass crucible is uniformly crystallized during pulling the silicon single crystal.
    Type: Grant
    Filed: March 29, 2000
    Date of Patent: August 28, 2001
    Assignees: Shin-Etsu Quartz Products Co. Ltd., Shin-Etsu Handotai Co., Ltd.
    Inventors: Hiroyuki Watanabe, Hiroyuki Miyazawa, Tatsuhiro Sato, Satoshi Soeta, Tetsuya Igarashi
  • Patent number: 5972106
    Abstract: A device and method for producing single crystals by the Czohralski method can control the temperature distribution and thermal history of single crystals to improve the production efficiency and quality of single crystals. The device includes a cylinder coaxially surrounding a single crystal pulling rod, having an upper end airtightly connected to the ceiling of a pulling chamber and a lower end close to the surface of a melt in a crucible. A heat insulating element is attached to the lower end of the cylinder, and is surrounded by a surface of the crystal, the inside wall of the crucible and the surface of the melt. The heat insulating element is sized to occupy 30-95% by volume of the space above the melt, and the space has a height corresponding to the radius of the crystal.
    Type: Grant
    Filed: February 10, 1997
    Date of Patent: October 26, 1999
    Assignee: Shin-Etsu Handotai Co., LTD.
    Inventors: Tomohiko Ohta, Susumu Sonokawa, Satoshi Soeta, Yoshihiro Kodama
  • Patent number: 5888298
    Abstract: A method, mechanisms and jig for handling a member of a crystal pulling apparatus are disclosed. The crystal pulling apparatus grows a single crystal from a melt of a crystalline material by a CZ method. Handling of a graphite crucible or the like of the crystal pulling apparatus, including a vertical moving operation, a swinging operation, or the like, is performed using a crane and a lifting jig. This makes it possible to readily move the member of the crystal pulling apparatus vertically and otherwise without relying on manual labor.
    Type: Grant
    Filed: December 5, 1996
    Date of Patent: March 30, 1999
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Takahiro Yanagimachi, Satoshi Soeta, Atsushi Iwasaki, Shinobu Takeyasu
  • Patent number: 5851287
    Abstract: A seed crystal holder is used to grow a single crystal in an intended direction. In order to grow a single crystal in an intended direction by a crystal pulling method, a seed crystal is accurately cut out along a crystal orientation, and this seed crystal is accurately held in a predetermined attitude by the seed crystal holder. A seed crystal insertion bore having a rectangular cross-section is formed in the body of the seed crystal holder. A seed crystal having a taper surface at one edge is inserted into the seed crystal insertion bore. The inserted seed crystal is pressed at its taper surface by a taper surface of a block, so that two surfaces of the seed crystal are fixedly pressed against two inner surfaces of the seed crystal insertion bore. The other end of the block is covered with a block-retaining ring, so that the block does not come off the seed crystal holder.
    Type: Grant
    Filed: February 20, 1997
    Date of Patent: December 22, 1998
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventor: Satoshi Soeta