Patents by Inventor Yasuyuki Sakaguchi
Yasuyuki Sakaguchi 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).
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Patent number: 11414546Abstract: An object of the present invention is to provide a resin composition having excellent heat resistance and excellent thermal adhesiveness, so as to provide an electric insulating sheet having excellent heat resistance. In order to achieve the aforementioned object, the present invention provides a resin composition which contains a polyether sulfone resin and a resin having a specific melt viscosity, and contains at least a phenoxy resin other than the polyether sulfone resin.Type: GrantFiled: July 18, 2019Date of Patent: August 16, 2022Assignee: NITTO SHINKO CORPORATIONInventors: Yasuyuki Kihara, Takahiro Sakaguchi, Jun Fujiki
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METHOD OF INSPECTING LUBRICATING OIL COMPOSITION AND METHOD OF PRODUCING LUBRICATING OIL COMPOSITION
Publication number: 20220074840Abstract: The invention provides a method of inspecting a lubricating oil composition and a method of producing a lubricating oil composition. The inspecting method is capable of stably reproducing wear resistance characteristics by using a relatively easy measuring method even in the case where the lubricating oil composition contains a fullerene. In the method of inspecting the lubricating oil composition, the particle size (r) of particles present in the lubricating oil composition containing a base oil and fullerene is measured, and the lubricating oil composition is sorted on the basis of a predetermined range of the particle size (r) set by the relationship between the measured value of the particle size (r) and the measured value of the wear coefficient of the lubricating oil composition.Type: ApplicationFiled: November 15, 2021Publication date: March 10, 2022Applicant: SHOWA DENKO K.K.Inventors: Ryuji MONDEN, Yasuyuki SAKAGUCHI, Hitomi KANE, Kunio KONDO -
Publication number: 20140339571Abstract: A SiC epitaxial wafer obtained by forming a SiC epitaxial layer on a 4H—SiC single-crystal substrate that is tilted at an off-angle of 0.4° to 5°, wherein linear density of step bunchings, which are connected to shallow pits which are due to screw dislocation in the SiC epitaxial wafer, is 5 mm?1 or less.Type: ApplicationFiled: July 30, 2014Publication date: November 20, 2014Applicant: SHOWA DENKO K.K.Inventors: Kenji MOMOSE, Yutaka TAJIMA, Yasuyuki SAKAGUCHI, Michiya ODAWARA, Yoshihiko MIYASAKA
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Patent number: 8823015Abstract: Provided is a silicon carbide epitaxial wafer, the entire surface of which is free of step bunching. Also provided is a method for manufacturing said silicon carbide epitaxial wafer. The provided method for manufacturing a silicon carbide semiconductor device includes: a step wherein a 4H—SiC single-crystal substrate having an off-axis angle of 5° or less is polished until the lattice disorder layer on the surface of the substrate is 3 nm or less; a step wherein, in a hydrogen atmosphere, the polished substrate is brought to a temperature between 1400° C. and 1600° C. and the surface of the substrate is cleaned; a step wherein silicon carbide is epitaxially grown on the surface of the cleaned substrate as the amounts of SiH4 gas and C3H8 gas considered necessary for epitaxially growing silicon carbide are supplied simultaneously at a carbon-to-silicon concentration ratio between 0.7 and 1.Type: GrantFiled: August 25, 2010Date of Patent: September 2, 2014Assignee: Showa Denko K.K.Inventors: Kenji Momose, Yutaka Tajima, Yasuyuki Sakaguchi, Michiya Odawara, Yoshihiko Miyasaka
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Patent number: 8513674Abstract: A method of manufacturing of a semiconductor device (101) includes: a fine pattern forming step of forming p-type impurity regions (3, 4) and surface ohmic contact electrodes (5) using a stepper, after forming an N-type epitaxial layer (2) on a SiC single-crystal substrate (1); a protective film planarizing step of forming a protective film so as to cover the surface ohmic contact electrodes (5) and performing planarization of the protective film; a substrate thinning step of thinning the SiC single-crystal substrate (1); a backside ohmic contact electrode forming step of forming a backside ohmic contact electrode (7) on the SiC single-crystal substrate (1); a surface Schottky contact electrode forming step of forming a Schottky metal portion (8) connected to the p-type impurity regions (3, 4) and the surface ohmic contact electrodes (5); and a step of forming a surface pad electrode (9) that covers the Schottky metal portion (8).Type: GrantFiled: November 25, 2009Date of Patent: August 20, 2013Assignee: Showa Denko K.K.Inventors: Akihiko Sugai, Yasuyuki Sakaguchi
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Publication number: 20120146056Abstract: Provided is a silicon carbide epitaxial wafer, the entire surface of which is free of step bunching. Also provided is a method for manufacturing said silicon carbide epitaxial wafer. The provided method for manufacturing a silicon carbide semiconductor device includes: a step wherein a 4H—SiC single-crystal substrate having an off-axis angle of 5° or less is polished until the lattice disorder layer on the surface of the substrate is 3 nm or less; a step wherein, in a hydrogen atmosphere, the polished substrate is brought to a temperature between 1400° C. and 1600° C. and the surface of the substrate is cleaned; a step wherein silicon carbide is epitaxially grown on the surface of the cleaned substrate as the amounts of SiH4 gas and C3H8 gas considered necessary for epitaxially growing silicon carbide are supplied simultaneously at a carbon-to-silicon concentration ratio between 0.7 and 1.Type: ApplicationFiled: August 25, 2010Publication date: June 14, 2012Applicant: SHOWA DENKO K.K.Inventors: Kenji Momose, Yutaka Tajima, Yasuyuki Sakaguchi, Michiya Odawara, Yoshihiko Miyasaka
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Publication number: 20110233563Abstract: A method of manufacturing of a semiconductor device (101) includes: a fine pattern forming step of forming p-type impurity regions (3, 4) and surface ohmic contact electrodes (5) using a stepper, after forming an N-type epitaxial layer (2) on a SiC single-crystal substrate (1); a protective film planarizing step of forming a protective film so as to cover the surface ohmic contact electrodes (5) and performing planarization of the protective film; a substrate thinning step of thinning the SiC single-crystal substrate (1); a backside ohmic contact electrode forming step of forming a backside ohmic contact electrode (7) on the SiC single-crystal substrate (1); a surface Schottky contact electrode forming step of forming a Schottky metal portion (8) connected to the p-type impurity regions (3, 4) and the surface ohmic contact electrodes (5); and a step of forming a surface pad electrode (9) that covers the Schottky metal portion (8).Type: ApplicationFiled: November 25, 2009Publication date: September 29, 2011Applicant: SHOWA DENKO K.K.Inventors: Akihiko Sugai, Yasuyuki Sakaguchi
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Patent number: 7993453Abstract: A method for the production of an SiC single crystal includes the steps of growing a first SiC single crystal in a first direction of growth on a first seed crystal formed of an SiC single crystal, disposing the first SiC single crystal grown on the first seed crystal in a direction parallel or oblique to the first direction of growth and cutting the disposed first SiC single crystal in a direction of a major axis in a cross section perpendicular to the first direction of growth to obtain a second seed crystal, using the second seed crystal to grow thereon in a second direction of growth a second SiC single crystal to a thickness greater than a length of the major axis in the cross section, disposing the second SiC single crystal grown on the second seed crystal in a direction parallel or oblique to the second direction of growth and cutting the disposed second SiC single crystal in a direction of a major axis in a cross section perpendicular to the second direction of growth to obtain a third seed crystal, uType: GrantFiled: May 10, 2007Date of Patent: August 9, 2011Assignee: Showa Denko K.K.Inventors: Naoki Oyanagi, Tomohiro Syounai, Yasuyuki Sakaguchi
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Publication number: 20110183113Abstract: There is provided a silicon carbide single crystal substrate having adhered particles that cause crystal defects removed therefrom and has high surface cleanliness, the silicon carbide single crystal substrate, wherein a density of first adhered particles attached onto one surface of the substrate and having a height of 100 nm or more is one particle/cm2 or less, and also a density of second adhered particles attached onto one surface of the substrate and having a height of less than 100 nm is 1,500 particles/cm2 or less.Type: ApplicationFiled: September 28, 2009Publication date: July 28, 2011Applicant: SHOWA DENKO K.K.Inventor: Yasuyuki Sakaguchi
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Publication number: 20100092366Abstract: A water-based polishing slurry for polishing a silicon carbide single crystal, wherein the slurry comprises abrasive particles having a mean particle size of 1 to 400 nm and an inorganic acid, and the slurry has a pH of less than 2 at 20° C.Type: ApplicationFiled: December 17, 2007Publication date: April 15, 2010Applicant: SHOWA DENKO K.K.Inventors: Hisao Kogoi, Naoki Oyanagi, Yasuyuki Sakaguchi
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Publication number: 20100028240Abstract: A method for producing an SiC single crystal comprises providing a low temperature region and a high temperature region in a crystal growth crucible (6); disposing a seed crystal substrate formed of an SiC single crystal in the low temperature region of the crystal growth crucible; disposing an SiC raw material in the high temperature region; and depositing a sublimation gas that sublimes from the SiC raw material on the seed crystal substrate to grow the SiC single crystal. A material used in the crucible member where the seed crystal is disposed is a material having a room-temperature linear expansion coefficient that differs from that of SiC by 1.0×10?6/K or less, and the crucible member where the seed crystal is disposed is made of Sic.Type: ApplicationFiled: October 4, 2007Publication date: February 4, 2010Inventors: Tomohiro Shonai, Hisao Kogoi, Yasuyuki Sakaguchi
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Publication number: 20090184327Abstract: A method for the production of an SiC single crystal includes the steps of growing a first SiC single crystal in a first direction of growth on a first seed crystal formed of an SiC single crystal, disposing the first SiC single crystal grown on the first seed crystal in a direction parallel or oblique to the first direction of growth and cutting the disposed first SiC single crystal in a direction of a major axis in a cross section perpendicular to the first direction of growth to obtain a second seed crystal, using the second seed crystal to grow thereon in a second direction of growth a second SiC single crystal to a thickness greater than a length of the major axis in the cross section, disposing the second SiC single crystal grown on the second seed crystal in a direction parallel or oblique to the second direction of growth and cutting the disposed second SiC single crystal in a direction of a major axis in a cross section perpendicular to the second direction of growth to obtain a third seed crystal, uType: ApplicationFiled: May 10, 2007Publication date: July 23, 2009Applicant: Showa Denko K.K.Inventors: Naoki Oyanagi, Tomohiro Syounai, Yasuyuki Sakaguchi
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Patent number: 7371281Abstract: A growth crucible (2) for depositing on a seed crystal substrate (5) a silicon carbide single crystal (6) using a sublimate gas of a silicon carbide raw material (11) is disposed inside of an outer crucible (1). During the course of silicon carbide single crystal, a silicon raw material (22) is continuously fed from outside into a space between the growth crucible and the outer crucible for the purpose of vaporizing the silicon raw material. An atmosphere gas surrounding the growth crucible is constituted of a silicon gas. The pressure of the atmosphere silicon gas is controlled to suppress a variation in the composition of the sublimate gas within the growth crucible to thereby grow a large-sized silicon carbide single crystal with few crystal defects on the seed crystal substrate reliably at a high growth rate.Type: GrantFiled: September 18, 2003Date of Patent: May 13, 2008Assignee: Showa Denko K.K.Inventors: Yasuyuki Sakaguchi, Atsushi Takagi, Naoki Oyanagi
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Publication number: 20060144324Abstract: A growth crucible (2) for depositing on a seed crystal substrate (5) a silicon carbide single crystal (6) using a sublimate gas of a silicon carbide raw material (11) is disposed inside of an outer crucible (1). During the course of silicon carbide single crystal, a silicon raw material (22) is continuously fed from outside into a space between the growth crucible and the outer crucible for the purpose of vaporizing the silicon raw material. An atmosphere gas surrounding the growth crucible is constituted of a silicon gas. The pressure of the atmosphere silicon gas is controlled to suppress a variation in the composition of the sublimate gas within the growth crucible to thereby grow a large-sized silicon carbide single crystal with few crystal defects on the seed crystal substrate reliably at a high growth rate.Type: ApplicationFiled: September 18, 2003Publication date: July 6, 2006Inventors: Yasuyuki Sakaguchi, Atsushi Takagi, Naoki Oyanagi
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Patent number: 7029940Abstract: Ammonia for use in the manufacture of a GaN-type compound semiconductor, filled in a charging container 18 such that at least a part of the ammonia is liquid and the liquid phase ammonia has a water concentration determined by a Fourier-transform infrared spectroscopy (FT-IR) of 0.5 vol ppm or less, is introduced in the gaseous state into a reaction chamber 11 housing therein a substrate 1, and a layer comprising a GaN-type compound started from this ammonia is formed on the substrate 1.Type: GrantFiled: April 12, 2004Date of Patent: April 18, 2006Assignee: Showa Denko Kabushiki KaishaInventors: Hideki Hayashida, Taizo Ito, Yasuyuki Sakaguchi
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Publication number: 20040192048Abstract: Ammonia for use in the manufacture of a GaN-type compound semiconductor, filled in a charging container 18 such that at least a part of the ammonia is liquid and the liquid phase ammonia has a water concentration determined by a Fourier-transform infrared spectroscopy (FT-IR) of 0.5 vol ppm or less, is introduced in the gaseous state into a reaction chamber 11 housing therein a substrate 1, and a layer comprising a GaN-type compound started from this ammonia is formed on the substrate 1.Type: ApplicationFiled: April 12, 2004Publication date: September 30, 2004Applicant: SHOWA DENKO K.K.Inventors: Hideki Hayashida, Taizo Ito, Yasuyuki Sakaguchi
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Patent number: 6719842Abstract: Ammonia for use in the manufacture of a GaN-type compound semiconductor, filled in a charging container 18 such that at least a part of the ammonia is liquid and the liquid phase ammonia has a water concentration determined by a Fourier-transform infrared spectroscopy (FT-IR) of 0.5 vol ppm or less, is introduced in the gaseous state into a reaction chamber 11 housing therein a substrate 1, and a layer comprising a GaN-type compound started from this ammonia is formed on the substrate 1.Type: GrantFiled: December 29, 1999Date of Patent: April 13, 2004Assignee: Showa Denko Kabushiki KaishaInventors: Hideki Hayashida, Taizo Ito, Yasuyuki Sakaguchi
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Publication number: 20030033973Abstract: Ammonia for use in the manufacture of a GaN-type compound semiconductor, filled in a charging container 18 such that at least a part of the ammonia is liquid and the liquid phase ammonia has a water concentration determined by a Fourier-transform infrared spectroscopy (FT-IR) of 0.5 vol ppm or less, is introduced in the gaseous state into a reaction chamber 11 housing therein a substrate 1, and a layer comprising a GaN-type compound started from this ammonia is formed on the substrate 1.Type: ApplicationFiled: December 29, 1999Publication date: February 20, 2003Inventors: HIDEKI HAYASHIDA, TAIZO ITO, YASUYUKI SAKAGUCHI
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Patent number: 5744829Abstract: An AlGaInP light-emitting diode includes a double hetero-junction light-emitting structure of (Al.sub.x Ga.sub.1-x).sub.y In.sub.1-y P on a GaAs substrate. A multi-film reflection layer is provided between the GaAs substrate and the double hetero-junction light-emitting structure. The layers forming the double hetero-junction are lattice matched with the GaAs substrate at an epitaxial growth temperature. A GaP current diffusion layer is disposed on the upper surface of the double hetero-junction light-emitting structure, and ohmic electrodes are provided on the underside of the GaAs substrate and on the upper surface of the current diffusion layer.Type: GrantFiled: December 26, 1996Date of Patent: April 28, 1998Assignee: Showa Denko K. K.Inventors: Shigetaka Murasato, Yasuyuki Sakaguchi
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Patent number: 5656829Abstract: A semiconductor light emitting diode includes a compound semiconductor substrate and a double-hetero structure of (Al.sub.x Ga.sub.1-x).sub.y In.sub.1-y P (0.ltoreq.x.ltoreq.1, 0<y<1) as an active layer, and an upper clad layer of the double-hetero structure has a larger band gap energy (Eg) than the band gap energy of the active layer and has a thickness of 3-50 .mu.m.Type: GrantFiled: July 5, 1995Date of Patent: August 12, 1997Assignee: Showa Denko K.K.Inventors: Yasuyuki Sakaguchi, Sigemasa Nakamura, Yasuo Hosokawa, Yutaka Saito