Patents by Inventor Takeshi Senda

Takeshi Senda 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: 10141180
    Abstract: A silicon wafer is manufactured by subjecting a silicon wafer sliced from a silicon single-crystal ingot grown by the Czochralski process to a rapid thermal process in which the silicon wafer is heated to a maximum temperature within a range of 1300 to 1380° C., and kept at the maximum temperature for 5 to 60 seconds; and removing a surface layer of the wafer where a semiconductor device is to be manufactured by a thickness of not less X [?m] which is calculated according to the below equations (1) to (3): X [?m]=a [?m]+b [?m]??(1); a [?m]=(0.0031×(said maximum temperature) [° C.]?3.1)×6.4×(cooling rate)?0.4 [° C./second]??(2); and b [?m]=a/(solid solubility limit of oxygen) [atoms/cm3]/(oxygen concentration in substrate) [atoms/cm3]??(3).
    Type: Grant
    Filed: July 31, 2014
    Date of Patent: November 27, 2018
    Assignee: GLOBALWAFERS JAPAN CO., LTD.
    Inventors: Koji Araki, Tatsuhiko Aoki, Haruo Sudo, Takeshi Senda
  • Patent number: 9421712
    Abstract: The present invention provides a method for stably and robustly laser-welding transparent resins together without compromising transparency. Before laser welding, the joining surface of at least a second transparent resin is subjected to photooxidation, thereby reducing the laser transmittance without reducing the visible light transmittance. A laser beam in the ultraviolet region at a wavelength of 400 nm or less, or a laser beam with a pulse width of 10 ps or less is irradiated while the second transparent resin is pressurized to perform laser welding.
    Type: Grant
    Filed: November 28, 2012
    Date of Patent: August 23, 2016
    Assignee: Hitachi, Ltd.
    Inventors: Satoshi Arai, Takeshi Senda
  • Patent number: 9059099
    Abstract: There is provided a thermal treatment method of a silicon wafer. The method includes the successive steps of: (a) terminating silicon atoms existing on an active surface of the silicon wafer with hydrogen, wherein the active surface is mirror-polished, and a semiconductor device is to be formed on the active surface; (b) terminating the silicon atoms existing on the active surface of the silicon wafer with fluorine; (c) rapidly heating the silicon wafer to a first temperature under an inert gas atmosphere or a reducing gas atmosphere, wherein the first temperature is in a range of 1300° C. to 1400° C.; (d) holding the silicon wafer at the first temperature for a certain time; and (e) rapidly cooling the silicon wafer.
    Type: Grant
    Filed: March 15, 2012
    Date of Patent: June 16, 2015
    Assignee: GLOBAL WAFERS JAPAN CO., LTD.
    Inventors: Takeshi Senda, Koji Araki
  • Patent number: 8999864
    Abstract: A silicon wafer for preventing a void defect in a bulk region from becoming source of contamination and slip generation in a device process is provided. And a heat-treating method thereof for reducing crystal defects such as COP in a region near the wafer surface to be a device active region is provided. The silicon wafer has a surface region 1 which is a defect-free region and a bulk region 2 including void defect of a polyhedron whose basic shape is an octahedron in which a corner portion of the polyhedron is in the curved shape and an inner-wall oxide film the void defect is removed. The silicon wafer is provided by performing a heat-treating method in which gas to be supplied, inner pressure of spaces and a maximum achievable temperature are set to a predetermined value when subjecting the silicon wafer produced by a CZ method to RTP.
    Type: Grant
    Filed: May 28, 2010
    Date of Patent: April 7, 2015
    Assignee: Global Wafers Japan Co., Ltd.
    Inventors: Takeshi Senda, Hiromichi Isogai, Eiji Toyoda, Koji Araki, Tatsuhiko Aoki, Haruo Sudo, Koji Izunome, Susumu Maeda, Kazuhiko Kashima, Hiroyuki Saito
  • Publication number: 20150044422
    Abstract: A silicon wafer is manufactured by subjecting a silicon wafer sliced from a silicon single-crystal ingot grown by the Czochralski process to a rapid thermal process in which the silicon wafer is heated to a maximum temperature within a range of 1300 to 1380° C., and kept at the maximum temperature for 5 to 60 seconds; and removing a surface layer of the wafer where a semiconductor device is to be manufactured by a thickness of not less X [?m] which is calculated according to the below equations (1) to (3): X[?m]=a[?m]+b[?m]??(1); a[?m]=(0.0031×(said maximum temperature)[° C.]?3.1)×6.4×(cooling rate)?0.4[° C./second] . . . (2); and b[?m]=a/(solid solubility limit of oxygen) [atoms/cm3]/(oxygen concentration in substrate) [atoms/cm3]??(3).
    Type: Application
    Filed: July 31, 2014
    Publication date: February 12, 2015
    Inventors: Koji ARAKI, Tatsuhiko AOKI, Haruo SUDO, Takeshi SENDA
  • Publication number: 20140332157
    Abstract: The present invention provides a method for stably and robustly laser-welding transparent resins together without compromising transparency. Before laser welding, the joining surface of at least a second transparent resin is subjected to photooxidation, thereby reducing the laser transmittance without reducing the visible light transmittance. A laser beam in the ultraviolet region at a wavelength of 400 nm or less, or a laser beam with a pulse width of 10 ps or less is irradiated while the second transparent resin is pressurized to perform laser welding.
    Type: Application
    Filed: November 28, 2012
    Publication date: November 13, 2014
    Inventors: Satoshi Arai, Takeshi Senda
  • Patent number: 8476149
    Abstract: A silicon wafer produced from a silicon single crystal ingot grown by Czochralski process is subjected to rapid heating/cooling thermal process at a maximum temperature (T1) of 1300° C. or more, but less than 1380° C. in an oxidizing gas atmosphere having an oxygen partial pressure of 20% or more, but less than 100%. The silicon wafer according to the invention has, in a defect-free region (DZ layer) including at least a device active region of the silicon wafer, a high oxygen concentration region having a concentration of oxygen solid solution of 0.7×1018 atoms/cm3 or more and at the same time, the defect-free region contains interstitial silicon in supersaturated state.
    Type: Grant
    Filed: July 30, 2009
    Date of Patent: July 2, 2013
    Assignee: Global Wafers Japan Co., Ltd.
    Inventors: Hiromichi Isogai, Takeshi Senda, Eiji Toyoda, Kumiko Murayama, Koji Izunome, Susumu Maeda, Kazuhiko Kashima, Koji Araki, Tatsuhiko Aoki, Haruo Sudo, Yoichiro Mochizuki, Akihiko Kobayashi, Senlin Fu
  • Publication number: 20130078588
    Abstract: A method for heat-treating a silicon wafer is provided in which in-plane uniformity in BMD density along a diameter of a bulk of the wafer grown by the CZ process can be improved. Further, a method for heat-treating a silicon wafer is provided in which in-plane uniformity in BMD size can also be improved and COP of a surface layer of the wafer can be reduced. The method includes a step of a first heat treatment in which the CZ silicon wafer is heated to a temperature from 1325 to 1400° C. in an oxidizing gas atmosphere, held at the temperature, and then cooled at a cooling rate of from 50 to 250° C./second, and a step of a second heat treatment in which the wafer is heated to a temperature from 900 to 1200° C. in a non-oxidizing gas atmosphere, held at the temperature, and then cooled.
    Type: Application
    Filed: September 25, 2012
    Publication date: March 28, 2013
    Applicant: Covalent Silicon Corporation
    Inventors: Takeshi Senda, Koji Araki, Tatsuhiko Aoki, Haruo Sudo, Susumu Maeda
  • Patent number: 8399341
    Abstract: The invention is to provide a method for heat treating a silicon wafer reducing grown-in defects while suppressing generation of slip during RTP and improving surface roughness of the wafer. The method performing a first heat treatment while introducing a rare gas, the first heat treatment comprising the steps of rapidly heating the wafer to T1 of 1300° C. or higher and the melting point of silicon or lower, keeping the wafer at T1, rapidly cooling the wafer to T2 of 400-800° C. and keeping the wafer at T2; and performing a second heat treatment while introducing an oxygen gas in an amount of 20-100 vol. %, the second heat treatment comprising the steps of keeping the wafer at T2, rapidly heating the wafer from T2 to T3 of 1250° C. or higher and the melting point of silicon or lower, keeping the wafer at T3 and rapidly cooling the wafer.
    Type: Grant
    Filed: May 17, 2010
    Date of Patent: March 19, 2013
    Assignee: Covalent Materials Corporation
    Inventors: Takeshi Senda, Hiromichi Isogai, Eiji Toyoda, Kumiko Murayama, Koji Araki, Tatsuhiko Aoki, Haruo Sudo, Koji Izunome, Susumu Maeda, Kazuhiko Kashima
  • Publication number: 20120241912
    Abstract: There is provided a thermal treatment method of a silicon wafer. The method includes the successive steps of: (a) terminating silicon atoms existing on an active surface of the silicon wafer with hydrogen, wherein the active surface is mirror-polished, and a semiconductor device is to be formed on the active surface; (b) terminating the silicon atoms existing on the active surface of the silicon wafer with fluorine; (c) rapidly heating the silicon wafer to a first temperature under an inert gas atmosphere or a reducing gas atmosphere, wherein the first temperature is in a range of 1300° C. to 1400° C.; (d) holding the silicon wafer at the first temperature for a certain time; and (e) rapidly cooling the silicon wafer.
    Type: Application
    Filed: March 15, 2012
    Publication date: September 27, 2012
    Applicant: Covalent Materials Corporation
    Inventors: Takeshi SENDA, Koji Araki
  • Patent number: 8252700
    Abstract: In a method of heat treating a wafer obtained by slicing a silicon single crystal ingot manufactured by the Czochralski method, a rapid heating/cooling heat treatment is carried out by setting a holding time at an ultimate temperature of 1200° C. or more and a melting point of silicon or less to be equal to or longer than one second and to be equal to or shorter than 60 seconds in a mixed gas atmosphere containing oxygen having an oxygen partial pressure of 1.0% or more and 20% or less and argon, and an oxide film having a thickness of 9.1 nm or less or 24.3 nm or more is thus formed on a surface of the silicon wafer.
    Type: Grant
    Filed: January 21, 2010
    Date of Patent: August 28, 2012
    Assignee: Covalent Materials Corporation
    Inventors: Takeshi Senda, Hiromichi Isogai, Eiji Toyoda, Kumiko Murayama, Koji Araki, Tatsuhiko Aoki, Haruo Sudo, Koji Izunome, Susumu Maeda, Kazuhiko Kashima
  • Publication number: 20120184091
    Abstract: The invention is to provide a method for heat treating a silicon wafer reducing grown-in defects while suppressing generation of slip during RTP and improving surface roughness of the wafer. The method performing a first heat treatment while introducing a rare gas, the first heat treatment comprising the steps of rapidly heating the wafer to T1 of 1300° C. or higher and the melting point of silicon or lower, keeping the wafer at T1, rapidly cooling the wafer to T2 of 400-800° C. and keeping the wafer at T2; and performing a second heat treatment while introducing an oxygen gas in an amount of 20-100 vol. %, the second heat treatment comprising the steps of keeping the wafer at T2, rapidly heating the wafer from T2 to T3 of 1250° C. or higher and the melting point of silicon or lower, keeping the wafer at T3 and rapidly cooling the wafer.
    Type: Application
    Filed: May 17, 2010
    Publication date: July 19, 2012
    Applicant: Covalent Materials Corporation
    Inventors: Takeshi Senda, Hiromichi Isogai, Eiji Toyoda, Kumiko Murayama, Koji Araki, Tatsuhiko Aoki, Haruo Sudo, Koji Izunome, Susumu Maeda, Kazuhiko Kashima
  • Publication number: 20120139088
    Abstract: A silicon wafer for preventing a void defect in a bulk region from becoming source of contamination and slip generation in a device process is provided. And a heat-treating method thereof for reducing crystal defects such as COP in a region near the wafer surface to be a device active region is provided. The silicon wafer has a surface region 1 which is a defect-free region and a bulk region 2 including void defect of a polyhedron whose basic shape is an octahedron in which a corner portion of the polyhedron is in the curved shape and an inner-wall oxide film the void defect is removed. The silicon wafer is provided by performing a heat-treating method in which gas to be supplied, inner pressure of spaces and a maximum achievable temperature are set to a predetermined value when subjecting the silicon wafer produced by a CZ method to RTP.
    Type: Application
    Filed: May 28, 2010
    Publication date: June 7, 2012
    Applicant: Covalent Materials Corporation
    Inventors: Takeshi Senda, Hiromichi Isogai, Eiji Toyoda, Koji Araki, Tatsuhiko Aoki, Haruo Sudo, Koji Izunome, Susumu Maeda, Kazuhiko Kashima, Hiroyuki Saito
  • Patent number: 7977219
    Abstract: In a manufacturing method for a silicon wafer, a first heat treatment process is performed on the silicon wafer while introducing a first gas having an oxygen gas in an amount of 0.01 vol. % or more and 1.00 vol. % or less and a rare gas, and a second heat treatment process is performed while stopping introducing the first gas and introducing a second gas having an oxygen gas in an amount of 20 vol. % or more and 100 vol. % or less and a rare gas. In the first heat treatment process, the silicon wafer is rapidly heated to first temperature of 1300° C. or higher and a melting point of silicon or lower at a first heating rate, and kept at the first temperature. In the second heat treatment process, the silicon wafer is kept at the first temperature, and rapidly cooled from the first temperature at a first cooling rate.
    Type: Grant
    Filed: July 30, 2009
    Date of Patent: July 12, 2011
    Assignee: Covalent Materials Corporation
    Inventors: Hiromichi Isogai, Takeshi Senda, Eiji Toyoda, Kumiko Murayama, Koji Izunome, Susumu Maeda, Kazuhiko Kashima
  • Publication number: 20100197146
    Abstract: In a method of heat treating a wafer obtained by slicing a silicon single crystal ingot manufactured by the Czochralski method, a rapid heating/cooling heat treatment is carried out by setting a holding time at an ultimate temperature of 1200° C. or more and a melting point of silicon or less to be equal to or longer than one second and to be equal to or shorter than 60 seconds in a mixed gas atmosphere containing oxygen having an oxygen partial pressure of 1.0% or more and 20% or less and argon, and an oxide film having a thickness of 9.1 nm or less or 24.3 nm or more is thus formed on a surface of the silicon wafer.
    Type: Application
    Filed: January 21, 2010
    Publication date: August 5, 2010
    Applicant: COVALENT MATERIALS CORPORATION
    Inventors: Takeshi Senda, Hiromichi Isogai, Eiji Toyoda, Kumiko Murayama, Koji Araki, Tatsuhiko Aoki, Haruo Sudo, Koji Izunome, Susumu Maeda, Kazuhiko Kashima
  • Patent number: 7679730
    Abstract: An image pickup device disposed in a predetermined position relative to a surface of a strained silicon wafer photographs the surface of the strained silicon wafer in a plurality of rotation angle positions on photographing conditions under which bright lines appearing on the surface of the strained silicon wafer can be photographed, in an environment where a light source device illuminates the surface of the strained silicon wafer which is rotating. A composite image in a predetermined angle position is generated from surface images of the strained silicon wafer in a plurality of rotation angle positions obtained by the image pickup device.
    Type: Grant
    Filed: September 13, 2007
    Date of Patent: March 16, 2010
    Assignees: Shibaura Mechatronics Corporation, Covalent Materials Corporation
    Inventors: Hideaki Takano, Miyuki Shimizu, Takeshi Senda, Koji Izunome, Yoshinori Hayashi, Kazuhiko Hamatani
  • Publication number: 20100055884
    Abstract: In a manufacturing method for a silicon wafer, a first heat treatment process is performed on the silicon wafer while introducing a first gas having an oxygen gas in an amount of 0.01 vol. % or more and 1.00 vol. % or less and a rare gas, and a second heat treatment process is performed while stopping introducing the first gas and introducing a second gas having an oxygen gas in an amount of 20 vol. % or more and 100 vol. % or less and a rare gas. In the first heat treatment process, the silicon wafer is rapidly heated to first temperature of 1300° C. or higher and a melting point of silicon or lower at a first heating rate, and kept at the first temperature. In the second heat treatment process, the silicon wafer is kept at the first temperature, and rapidly cooled from the first temperature at a first cooling rate.
    Type: Application
    Filed: July 30, 2009
    Publication date: March 4, 2010
    Inventors: Hiromichi Isogai, Takeshi Senda, Eiji Toyoda, Kumiko Murayama, Koji Izunome, Susumu Maeda, Kazuhiko Kashima
  • Publication number: 20100038757
    Abstract: A silicon wafer produced from a silicon single crystal ingot grown by Czochralski process is subjected to rapid heating/cooling thermal process at a maximum temperature (T1) of 1300° C. or more, but less than 1380° C. in an oxidizing gas atmosphere having an oxygen partial pressure of 20% or more, but less than 100%. The silicon wafer according to the invention has, in a defect-free region (DZ layer) including at least a device active region of the silicon wafer, a high oxygen concentration region having a concentration of oxygen solid solution of 0.7×1018 atoms/cm3 or more and at the same time, the defect-free region contains interstitial silicon in supersaturated state.
    Type: Application
    Filed: July 30, 2009
    Publication date: February 18, 2010
    Inventors: Hiromichi Isogai, Takeshi Senda, Eiji Toyoda, Kumiko Murayama, Koji Izunome, Susumu Maeda, Kazuhiko Kashima, Koji Araki, Tatsuhiko Aoki, Haruo Sudo, Yoichiro Mochizuki, Akihiko Kobayashi, Senlin Fu
  • Publication number: 20090004825
    Abstract: A method of manufacturing a semiconductor substrate having a DSB structure that enables simplification of a manufacturing process by optimizing a total thickness of oxides on surfaces of two wafers before being bonded together is provided. The method comprises a process of preparing a first semiconductor wafer and a second semiconductor wafer, a process of bonding the first semiconductor wafer and second semiconductor wafer when a total of thickness of an oxide on the surface of the first semiconductor wafer and that of an oxide on the surface of the second semiconductor wafer is 0.4 nm or more and 1.0 nm or less, and a process of providing heat treatment to a semiconductor substrate after the process of the bonding and before a process of thinning one of the wafers.
    Type: Application
    Filed: January 4, 2008
    Publication date: January 1, 2009
    Applicant: Covalent Materials Corporation
    Inventors: Takeshi SENDA, Hiromichi ISOGAI, Eiji TOYODA, Akiko NARITA, Koji IZUNOME
  • Publication number: 20080164572
    Abstract: A semiconductor substrate whose surface roughness is reduced by optimizing an inclination (off angle) with respect to a {110} surface of the semiconductor substrate surface and a manufacturing method thereof are provided. The surface of the semiconductor substrate has the inclination (off angle) of 0 degree or more and 0.12 degrees or less, or 5 degrees or more and 11 degrees or less, preferably 6 degrees or more and 9 degrees or less with respect to the {110} surface. The manufacturing method of a semiconductor substrate has a process in which a semiconductor single crystal ingot is sliced at an inclination (off angle) of 5 degrees or more and 11 degrees or less, preferably 6 degrees or more and 9 degrees or less with respect to the {110} surface.
    Type: Application
    Filed: December 19, 2007
    Publication date: July 10, 2008
    Applicant: Covalent Materials Corporation
    Inventors: Eiji Toyoda, Takeshi Senda, Akiko Narita, Hiromichi Isogai, Koji Izunome