Patents by Inventor Yuuji Tobisaka

Yuuji Tobisaka 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: 20110111574
    Abstract: A nitride-based semiconductor crystal and a second substrate are bonded together. In this state, impact is applied externally to separate the low-dislocation density region of the nitride-based semiconductor crystal along the hydrogen ion-implanted layer, thereby transferring (peeling off) the surface layer part of the low-dislocation density region onto the second substrate. At this time, the lower layer part of the low-dislocation density region stays on the first substrate without being transferred onto the second substrate. The second substrate onto which the surface layer part of the low-dislocation density region has been transferred is defined as a semiconductor substrate available by the manufacturing method of the present invention, and the first substrate on which the lower layer part of the low-dislocation density region stays is reused as a substrate for epitaxial growth.
    Type: Application
    Filed: January 20, 2011
    Publication date: May 12, 2011
    Applicant: Shin-Etsu Chemical Co., Ltd.
    Inventors: Shoji AKIYAMA, Yoshihiro Kubota, Atsuo Ito, Makoto Kawai, Yuuji Tobisaka, Koichi Tanaka
  • Patent number: 7935611
    Abstract: A silicon layer having a conductivity type opposite to that of a bulk is provided on the surface of a silicon substrate and hydrogen ions are implanted to a predetermined depth into the surface region of the silicon substrate through the silicon layer to form a hydrogen ion-implanted layer. Then, an n-type germanium-based crystal layer whose conductivity type is opposite to that of the silicon layer and a p-type germanium-based crystal layer whose conductivity type is opposite to that of the germanium-based crystal layer are successively vapor-phase grown to provide a germanium-based crystal. The surface of the germanium-based crystal layer and the surface of the supporting substrate are bonded together. In this state, impact is applied externally to separate a silicon crystal from the silicon substrate along the hydrogen ion-implanted layer, thereby transferring a laminated structure composed of the germanium-based crystal and the silicon crystal onto the supporting substrate.
    Type: Grant
    Filed: March 12, 2007
    Date of Patent: May 3, 2011
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Shoji Akiyama, Yoshihiro Kubota, Atsuo Ito, Makoto Kawai, Yuuji Tobisaka, Koichi Tanaka
  • Patent number: 7892934
    Abstract: On the side of a surface (the bonding surface side) of a single crystal Si substrate, a uniform ion implantation layer is formed at a prescribed depth (L) in the vicinity of the surface. The surface of the single crystal Si substrate and a surface of a transparent insulating substrate as bonding surfaces are brought into close contact with each other, and bonding is performed by heating the substrates in this state at a temperature of 350° C. or below. After this bonding process, an Si—Si bond in the ion implantation layer is broken by applying impact from the outside, and a single crystal silicon thin film is mechanically peeled along a crystal surface at a position equivalent to the prescribed depth (L) in the vicinity of the surface of the single crystal Si substrate.
    Type: Grant
    Filed: November 1, 2006
    Date of Patent: February 22, 2011
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Makoto Kawai, Yoshihiro Kubota, Atsuo Ito, Koichi Tanaka, Yuuji Tobisaka, Shoji Akiyama
  • Patent number: 7879175
    Abstract: Wettability of a PBN material surface with respect to a metal is improved to expand use applications. Hydrogen ions are implanted into a surface of a silicon substrate 10 to form an ion implanted region 11 at a predetermined depth near a surface of the silicon substrate 10, and a plasma treatment or an ozone treatment is performed with respect to a main surface of the silicon substrate 10 for the purpose of surface cleaning or surface activation. The main surfaces of the silicon substrate 10 and a PBN substrate 20 subjected to the surface treatment are appressed against each other to be bonded at a room temperature, and an external impact shock is given to the bonded substrate to mechanically delaminate a silicon film 12 from a bulk 13 of the silicon substrate to be transferred. An obtained PBN composite substrate 30 is diced to form a chip having a desired size, and a refractory metal is metallized on the silicon film 12 side to be connected with a wiring material.
    Type: Grant
    Filed: March 28, 2008
    Date of Patent: February 1, 2011
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Makoto Kawai, Yoshihiro Kubota, Atsuo Ito, Koichi Tanaka, Yuuji Tobisaka, Shoji Akiyama
  • Patent number: 7855127
    Abstract: A method for manufacturing a semiconductor substrate including: epitaxially growing a silicon germanium (SiGe) film on a silicon (Si) substrate by a chemical vapor deposition method; subjecting a heat treatment to the SiGe film at a temperature of not less than 700° C. and not more than 1200° C.; implanting hydrogen ions into a surface of the SiGe film; subjecting a surface activation treatment to a main surface of at least one of the SiGe film and a support substrate; bonding main surfaces of the SiGe film and the support substrate at a temperature of not less than 100° C. and not more than 400° C.; and applying an external impact to a bonding interface between the SiGe film and the support substrate to delaminate the SiGe crystal along a hydrogen ion implanted interface of the SiGe film, thereby forming a SiGe thin film on the main surface of the support substrate.
    Type: Grant
    Filed: January 29, 2008
    Date of Patent: December 21, 2010
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Shoji Akiyama, Yoshihiro Kubota, Atsuo Ito, Koichi Tanaka, Makoto Kawai, Yuuji Tobisaka
  • Publication number: 20100311221
    Abstract: Hydrogen ions are implanted to a surface (main surface) of the single crystal Si substrate 10 at a dosage of 1.5×1017 atoms/cm2 or higher to form the hydrogen ion implanted layer (ion-implanted damage layer) 11. As a result of the hydrogen ion implantation, the hydrogen ion implanted boundary 12 is formed. The single crystal Si substrate 10 and the low melting glass substrate 20 are bonded together. The bonded substrate is heated at relatively low temperature, 120° C. or higher and 250° C. or lower (below a melting point of the support substrate). Further, an external shock is applied to delaminate the Si crystal film along the hydrogen ion implanted boundary 12 of the single crystal Si substrate 10 out of the heat-treated bonded substrate. Then, the surface of the resultant silicon thin film 13 is polished to remove a damaged portion, so that a semiconductor substrate can be fabricated.
    Type: Application
    Filed: August 6, 2010
    Publication date: December 9, 2010
    Applicant: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Shoji Akiyama, Yoshihiro Kubota, Atsuo Ito, Koichi Tanaka, Makoto Kawai, Yuuji Tobisaka
  • Publication number: 20100289115
    Abstract: An oxide film having a thickness “tox” of not less than 0.2 ?m is provided on the bonding surface of a single-crystal silicon substrate. In a method for manufacturing an SOI substrate according to the present invention, a low-temperature process is employed to suppress the occurrence of thermal strain attributable to a difference in the coefficient of thermal expansion between the silicon substrate and a quartz substrate. To this end, the thickness “tox” of the oxide film is set to a large value of not less than 0.2 ?m to provide sufficient mechanical strength to the thin film to be separated and, at the same time, to allow strain to be absorbed in and relaxed by the relatively thick oxide film to suppress the occurrence of transfer defects during the step of separation.
    Type: Application
    Filed: February 8, 2007
    Publication date: November 18, 2010
    Applicant: Shin-Etsu Chemical Co.,Ltd.
    Inventors: Shoji Akiyama, Yoshihiro Kubota, Atsuo Ito, Koichi Tanaka, Makoto Kawai, Yuuji Tobisaka
  • Patent number: 7833878
    Abstract: A hydrogen ion-implanted layer is formed on the surface side of a first substrate which is a single-crystal silicon substrate. At least one of the surface of a second substrate, which is a transparent insulating substrate, and the surface of the first substrate is subjected to surface activation treatment, and the two substrates are bonded together. The bonded substrate composed of the single-crystal Si substrate and the transparent insulating substrate thus obtained is mounted on a susceptor and is placed under an infrared lamp. Light having a wave number range including an Si—H bond absorption band is irradiated at the bonded substrate for a predetermined length of time to break the Si—H bonds localized within a “microbubble layer” in the hydrogen ion-implanted layer, thereby separating a silicon thin film layer.
    Type: Grant
    Filed: February 8, 2007
    Date of Patent: November 16, 2010
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Shoji Akiyama, Yoshihiro Kubota, Atsuo Ito, Makoto Kawai, Yuuji Tobisaka, Koichi Tanaka
  • Patent number: 7823418
    Abstract: A glass base material manufacturing apparatus for manufacturing a glass base material comprising: a plurality burners, arranged in a row at a predetermined intervals along the longitudinal direction of a starting base material of the glass base material, for forming a deposit, which is a base material of the glass base material by depositing glass soot on the starting base material while moving reciprocatory over a section of the entire length of the starting base material along the longitudinal direction of the starting base material; a plurality of flow rate regulators, at least one of which is connected to the plurality of burners, respectively, for regulating a flow rate of raw material gas of the glass soot, which is supplied to the plurality of burners; and a control unit connected to each of the plurality of flow rate regulators for controlling individually the plurality of flow rate regulators.
    Type: Grant
    Filed: May 31, 2006
    Date of Patent: November 2, 2010
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Tadakatsu Shimada, Yuuji Tobisaka, Kazuhisa Hatayama, Hideo Hirasawa
  • Patent number: 7799589
    Abstract: An optical waveguide apparatus having a very simple structure that can modulate a signal light guided through an optical waveguide is provided. A photoresist 13 is applied to an upper side of an SOI film 12, a photoresist mask 14 is formed, and the SOI film in a region that is not covered with the photoresist mask 14 is removed by etching to obtain an optical waveguide 15 having a single-crystal silicon core. Further, a light emitting device capable of irradiating the single-crystal silicon core with a light having a wavelength of 1.1 ?m or below is provided on a back surface side of a quartz substrate 20 to provide an optical waveguide apparatus. When the light emitting device 30 does not apply a light, the light guided through the optical waveguide 15 is guided as it is.
    Type: Grant
    Filed: March 20, 2008
    Date of Patent: September 21, 2010
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Shoji Akiyama, Yoshihiro Kuboto, Atsuo Ito, Koichi Tanaka, Yuuji Tobisaka, Makoto Kawai
  • Publication number: 20100233866
    Abstract: A nitride-based semiconductor crystal and a second substrate are bonded together. In this state, impact is applied externally to separate the low-dislocation density region of the nitride-based semiconductor crystal along the hydrogen ion-implanted layer, thereby transferring (peeling off) the surface layer part of the low-dislocation density region onto the second substrate. At this time, the lower layer part of the low-dislocation density region stays on the first substrate without being transferred onto the second substrate. The second substrate onto which the surface layer part of the low-dislocation density region has been transferred is defined as a semiconductor substrate available by the manufacturing method of the present invention, and the first substrate on which the lower layer part of the low-dislocation density region stays is reused as a substrate for epitaxial growth.
    Type: Application
    Filed: February 8, 2007
    Publication date: September 16, 2010
    Applicant: Shin-Etsu Chemical Co., Ltd.
    Inventors: Shoji Akiyama, Yoshihiro Kubota, Atsuo Ito, Makoto Kawai, Yuuji Tobisaka, Koichi Tanaka
  • Publication number: 20100227452
    Abstract: A heating plate having a smooth surface is placed on a hot plate which constitutes a heating section, and the smooth surface of the heating plate is closely adhered on the rear surface of a single-crystal Si substrate bonded to a transparent insulating substrate. The temperature of the heating plate is kept at 200° C. or higher but not higher than 350° C. When the rear surface of the single-crystal Si substrate bonded to the insulating substrate is closely adhered on the heating plate, the single-crystal Si substrate is heated by thermal conduction, and a temperature difference is generated between the single-crystal Si substrate and the transparent insulating substrate. A large stress is generated between the both substrates due to rapid expansion of the single-crystal Si substrate, thus separation takes place at a hydrogen ion-implanted interface.
    Type: Application
    Filed: February 8, 2007
    Publication date: September 9, 2010
    Applicant: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Shoji Akiyama, Yoshihiro Kubota, Atsuo Ito, Makoto Kawai, Yuuji Tobisaka, Koichi Tanaka
  • Patent number: 7790571
    Abstract: A method of manufacturing an SOQ substrate and an SOQ substrate manufactured by the same are disclosed. In the method, hydrogen ions are implanted to a surface of a single crystal Si substrate through an oxide film to uniformly form an ion implanted layer at a predetermined depth from the surface of the single crystal Si substrate, and a bonding surface of the substrate undergoes a plasma treatment or an ozone treatment. An external shock is applied onto the single crystal Si substrate and quartz substrate, which are bonded together, to mechanically delaminate a silicon film from a single crystal silicon bulk. In this way, the SOQ film is formed on the quartz substrate through the oxide film. To further smooth the SOQ film surface, hydrogen heat treatment is performed at a temperature of 1000° C. or less below a quartz glass transition point.
    Type: Grant
    Filed: November 14, 2007
    Date of Patent: September 7, 2010
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Shoji Akiyama, Yoshihiro Kubota, Atsuo Ito, Koichi Tanaka, Makoto Kawai, Yuuji Tobisaka
  • Patent number: 7732867
    Abstract: Hydrogen ions are implanted to a surface (main surface) of the single crystal Si substrate 10 to form the hydrogen ion implanted layer (ion-implanted damage layer) 11. As a result of the hydrogen ion implantation, the hydrogen ion implanted boundary 12 is formed. The single crystal Si substrate 10 is bonded to the quartz substrate 20 having a carbon concentration of 100 ppm or higher, and an external shock is applied near the ion-implanted damage layer 11 to delaminate the Si crystal film along the hydrogen ion implanted boundary 12 of the single crystal Si substrate 10 out of the bonded substrate. Then, the surface of the resultant silicon thin film 13 is polished to remove a damaged portion, so that an SOQ substrate can be fabricated. There can be provided an SOQ substrate highly adaptable to a semiconductor device manufacturing process.
    Type: Grant
    Filed: November 2, 2007
    Date of Patent: June 8, 2010
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Shoji Akiyama, Yoshihiro Kubota, Atsuo Ito, Koichi Tanaka, Makoto Kawai, Yuuji Tobisaka
  • Patent number: 7696059
    Abstract: A consistent reduction in temperature in an SOI substrate manufacturing process is achieved. A gate oxide film provided on an SOI substrate is obtained by laminating a low-temperature thermal oxide film 13 grown at a temperature of 450° C. or below and an oxide film 14 obtained based on a CVD method. Since the thermal oxide film 13 is a thin film of 100 ? or below, a low temperature of 450° C. or below can suffice. The underlying thermal oxide film 13 can suppress a structural defect, e.g., an interface state, and the CVD oxide film 14 formed on the thermal oxide film can be used to adjust a thickness of the gate oxide film. According to such a technique, a conventional general silicon oxide film forming apparatus can be used to form the gate oxide film at a low temperature, thereby achieving a consistent reduction in temperature in the SOI substrate manufacturing process.
    Type: Grant
    Filed: October 3, 2008
    Date of Patent: April 13, 2010
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Shoji Akiyama, Yoshihiro Kubota, Atsuo Ito, Makoto Kawai, Yuuji Tobisaka, Koichi Tanaka
  • Publication number: 20100084746
    Abstract: A method of manufacturing a laminated substrate is provided. The method includes: forming an oxide film on at least a surface of a first substrate having a hardness of equal to or more than 150 GPa in Young's modulus, and then smoothing the oxide film; implanting hydrogen ions or rare gas ions, or mixed gas ions thereof from a surface of a second substrate to form an ion-implanted layer inside the substrate, laminating the first substrate and the second substrate through at least the oxide film, and then detaching the second substrate in the ion-implanted layer to form a laminated substrate, heat-treating the laminated substrate and diffusing outwardly the oxide film.
    Type: Application
    Filed: August 28, 2009
    Publication date: April 8, 2010
    Applicant: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Shoji AKIYAMA, Atsuo ITO, Yoshihiro KUBOTA, Koichi TANAKA, Makoto KAWAI, Yuuji TOBISAKA
  • Patent number: 7691724
    Abstract: A method for manufacturing an SOI substrate, including the steps of implanting hydrogen ions from a main surface of a single-crystal silicon substrate having an interstitial oxygen concentration which is equal to or below 1×1018 cm?3; performing an activation treatment with respect to the main surface of at least one of a transparent insulative substrate and the silicon substrate; bonding the main surface of the transparent insulative substrate to the main surface of the silicon substrate at a room temperature; performing a heat treatment with respect to the bonded substrate at a temperature falling within the range of 350° C. to 550° C. and having a cooling rate after the heat treatment that is equal to or below 5° C./minute; and mechanically delaminating a silicon thin film from the silicon substrate to form a silicon film on the main surface of the transparent insulative substrate.
    Type: Grant
    Filed: March 18, 2008
    Date of Patent: April 6, 2010
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Makoto Kawai, Yoshihiro Kubota, Atsuo Ito, Koichi Tanaka, Yuuji Tobisaka, Shoji Akiyama
  • Publication number: 20100025804
    Abstract: On the side of a surface (the bonding surface side) of a single crystal Si substrate, a uniform ion implantation layer is formed at a prescribed depth (L) in the vicinity of the surface. The surface of the single crystal Si substrate and a surface of a transparent insulating substrate as bonding surfaces are brought into close contact with each other, and bonding is performed by heating the substrates in this state at a temperature of 350° C. or below. After this bonding process, an Si—Si bond in the ion implantation layer is broken by applying impact from the outside, and a single crystal silicon thin film is mechanically peeled along a crystal surface at a position equivalent to the prescribed depth (L) in the vicinity of the surface of the single crystal Si substrate.
    Type: Application
    Filed: November 1, 2006
    Publication date: February 4, 2010
    Applicant: SHIN-ETSU CHEMICAL CO., LTD
    Inventors: Makoto Kawai, Yoshihiro Kubota, Atsuo Ito, Koichi Tanaka, Yuuji Tobisaka, Shoji Akiyama
  • Patent number: 7615456
    Abstract: A method for manufacturing an SOI substrate superior in film thickness uniformity and resistivity uniformity in a substrate surface of a silicon layer having a film thickness reduced by an etch-back method is provided. After B ions is implanted into a front surface of a single-crystal Si substrate 10 to form a high-concentration boron added p layer 11 having a depth L in the outermost front surface, the single-crystal Si substrate 10 is appressed against a quartz substrate 20 to be bonded at a room temperature. Chemical etching is performed with respect to the single-crystal Si substrate 10 from a back surface thereof to set its thickness to L or below. A heat treatment is carried out with respect to an SOI substrate in a hydrogen containing atmosphere to outwardly diffuse B from the high-concentration boron added p layer 11, thereby acquiring a boron added p layer 12 having a desired resistance value.
    Type: Grant
    Filed: March 25, 2008
    Date of Patent: November 10, 2009
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Shoji Akiyama, Yoshihiro Kubota, Atsuo Ito, Makoto Kawai, Yuuji Tobisaka, Koichi Tanaka
  • Patent number: 7595866
    Abstract: A method for measuring non-circularity of a core portion of an optical fiber base material includes a distribution measuring step of (i) moving the optical fiber base material in a direction parallel to a central axis of the core portion while light is irradiated, in a direction perpendicular to the central axis, to the optical fiber base material which is immersed in the matching oil, and (ii) recording a variation in a width of a portion of the irradiated light which transmits through the core portion in association with a moved distance of the optical fiber base material, thereby measuring a distribution of relative values of an outer diameter of the core portion in terms of a longitudinal direction of the optical fiber base material, a distribution storing step of performing the distribution measuring step each time the optical fiber base material is rotated about the central axis by a predetermined angle, thereby recording a plurality of distributions of the relative values of the outer diameter of the c
    Type: Grant
    Filed: August 21, 2007
    Date of Patent: September 29, 2009
    Assignee: Shin Etsu Chemical Co., Ltd.
    Inventors: Yuuji Tobisaka, Tetsuya Otosaka, Hiroshi Oyamada