Patents by Inventor Hiroyuki Ichikawa

Hiroyuki Ichikawa 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: 20190088483
    Abstract: A process of forming a gate electrode in an electrode device is disclosed. The process includes steps of, depositing an insulating film on a nitride semiconductor layer; forming a photoresist with an opening corresponding to the gate electrode on the insulating film; forming a recess in the insulating film using the photoresist as an etching mask, the recess leaving a rest portion in the insulating film; exposing the photoresist in oxygen plasma; baking the photoresist to make an edge of the opening thereof dull; etching the rest portion of the insulating film using the dulled photoresist as an etching mask; and forming the gate electrode so as to be in contact with the semiconductor layer through the opening in the insulating film.
    Type: Application
    Filed: September 20, 2018
    Publication date: March 21, 2019
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Tomohiro YOSHIDA, Hiroyuki ICHIKAWA
  • Publication number: 20180277434
    Abstract: A process of forming an ohmic electrode containing aluminum (Al) on a nitride semiconductor material is disclosed. The process includes steps of: (a) depositing an ohmic metal on the semiconductor material; (b) forming an insulating film such that the insulating film covers a side of the ohmic metal but exposes a top of the ohmic metal; and (c) alloying the ohmic metal at a temperature higher than 500° C. for 30 to 60 seconds.
    Type: Application
    Filed: March 22, 2018
    Publication date: September 27, 2018
    Applicants: Sumitomo Electric Industries, Ltd., SUMITOMO ELECTRIC DEVICE INNOVATIONS, INC.
    Inventors: Hiroyuki Ichikawa, Masahiro Nishi
  • Publication number: 20180053648
    Abstract: A method of manufacturing a semiconductor device according to an embodiment of the present invention includes steps of forming an AlN layer on a SiC substrate under conditions of a growth temperature of 1100° C. or lower, growth pressure of 100 torr or less and a V/III ratio of source gasses of 500 or less, forming a channel layer made of a nitride semiconductor, forming an electron supply layer, and forming gate, source, and drain electrodes.
    Type: Application
    Filed: October 13, 2017
    Publication date: February 22, 2018
    Inventors: Ken Nakata, Keiichi Yui, Hiroyuki Ichikawa, Isao Makabe, Tsuyoshi Kouchi
  • Patent number: 9551396
    Abstract: Provided is a vibration damping device having a novel structure and that can have a greatly increased load strength resistance without a concomitant increase in the number of components or size at a stopper mechanism. The structure is such that first and second stopper portions having a hanging plate part and a dip part are provided to a pair of opposing sides of a stopper plate of a vibration damping device, whereas a pair of side plate portions extending between the first and second stopper portions are provided to the other pair of opposing sides of the stopper plate, and openings at both sides of the first and second stopper portions are closed by the pair of side plate portions.
    Type: Grant
    Filed: June 2, 2014
    Date of Patent: January 24, 2017
    Assignees: SUMITOMO RIKO COMPANY LIMITED, TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Noriaki Yoshii, Hiroki Mizukawa, Yorishige Shimizu, Hiroyuki Ichikawa, Katsuhiko Katagiri, Shinji Komura
  • Patent number: 9394964
    Abstract: A fluid-filled vibration damping device including a second orifice passage and a third orifice passage tuned to a lower frequency than the second orifice passage, and an actuator including an output portion facing openings of the second and third orifice passages on a side of an equilibrium chamber via a flexible film. The flexible film obstructs the openings of the second and third orifice passages when the output portion comes into contact against a partition member so that the third orifice passage is blocked while the second orifice passage is substantially placed in communication owing to a center recess of the output portion permitting deformation of the flexible film. Meanwhile, the flexible film is separated from the openings of the second and third orifice passages when the output portion is separated from the partition member so that the two orifice passages are placed in communication.
    Type: Grant
    Filed: October 22, 2013
    Date of Patent: July 19, 2016
    Assignee: SUMITOMO RIKO COMPANY LIMITED
    Inventors: Takayoshi Yasuda, Hiroyuki Ichikawa, Akio Saiki
  • Patent number: 9390701
    Abstract: An active vibration or noise suppression system is provided that achieves fast convergence of vibration or noise. A sine wave control signal y(n) is constituted by frequency of a vibration or noise source, and an amplitude filter coefficient a(n) and a phase filter coefficient ?(n) as an adaptive filter coefficient. The sine wave control signal y(n) is expressed by a sine wave having an amplitude component and a phase component, and each of an amplitude update term ?a(n+1) and a phase update term ??(n+1) includes a sine wave or cosine wave term having an amplitude component and a phase component. The phase component of the sine wave control signal y(n) is multiplied by a coefficient other than 1, or the phase component of the sine wave or cosine wave term of each of the amplitude update term ?a(n+1) and the phase update term ??(n+1) is multiplied by a coefficient other than 1.
    Type: Grant
    Filed: April 5, 2013
    Date of Patent: July 12, 2016
    Assignee: SUMITOMO RIKO COMPANY LIMITED
    Inventors: Takayoshi Yasuda, Hiroyuki Ichikawa, Katsuhiro Goto
  • Patent number: 9360079
    Abstract: A vibration damping device including a first mounting member arranged on a lower side of a second mounting member, the first and second mounting members being elastically connected by a main rubber elastic body, and an outer bracket arranged on the lower side of the second mounting member. A coupling part is constituted by engagement between a bottom edge of the second mounting member and a top edge of the outer bracket, and the second mounting member is configured to be attached to a vibration source via the outer bracket. The outer bracket is arranged in opposition to the first mounting member in an axis-perpendicular direction, and an axis-perpendicular stopper member that regulates relative displacement between the first and second mounting members in the axis-perpendicular direction is constituted by contact between the first mounting member and the outer bracket.
    Type: Grant
    Filed: May 13, 2014
    Date of Patent: June 7, 2016
    Assignee: SUMITOMO RIKO COMPANY LIMITED
    Inventors: Hiroyuki Ichikawa, Takayoshi Yasuda, Akio Saiki
  • Publication number: 20160116018
    Abstract: Provided is a vibration damping device having a novel structure and that can have a greatly increased load strength resistance without a concomitant increase in the number of components or size at a stopper mechanism. The structure is such that first and second stopper portions having a hanging plate part and a dip part are provided to a pair of opposing sides of a stopper plate of a vibration damping device, whereas a pair of side plate portions extending between the first and second stopper portions are provided to the other pair of opposing sides of the stopper plate, and openings at both sides of the first and second stopper portions are closed by the pair of side plate portions.
    Type: Application
    Filed: June 2, 2014
    Publication date: April 28, 2016
    Applicants: Sumitomo Riko Company Limited, TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Noriaki YOSHII, Hiroki MIZUKAWA, Yorishige SHIMIZU, Hiroyuki ICHIKAWA, Katsuhiko KATAGIRI, Shinji KOMURA
  • Patent number: 9175739
    Abstract: An engine mount for use in a power unit vibration damping support structure configured to be mounted on a transmission side in a state without a distributed support load of a weight of the power unit being applied, the engine mount including: an inner shaft member; an outer tube member arranged separated to an outer circumference side of the inner shaft member; and a main rubber elastic body fixed to the inner shaft member while being attached to the outer tube member non-adhesively such that the inner shaft member and the outer tube member are elastically connected by the main rubber elastic body, wherein the outer tube member is configured to be attached to the power unit, and the inner shaft member is configured to be attached to a vehicle body.
    Type: Grant
    Filed: April 14, 2014
    Date of Patent: November 3, 2015
    Assignees: SUMITOMO RIKO COMPANY LIMITED, TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Masahiro Ohnishi, Akio Saiki, Takayoshi Yasuda, Hiroyuki Ichikawa, Nobuya Yoshida, Hiroshi Miya
  • Patent number: 9159821
    Abstract: A GaN device suppressing the instantaneous current reduction after the shut-off of a high frequency signal is disclosed. The GaN device provides, on a SiC substrate, an AlN layer, a GaN layer, and an AlGaN layer, The SiC substrate has an energy difference greater than 0.67 eV but less than 1.43 eV; the AlN layer has a thickness less than 50 nm; and the GaN layer has a thickness less than 1.5 ?m.
    Type: Grant
    Filed: December 27, 2013
    Date of Patent: October 13, 2015
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Ken Nakata, Keiichi Yui, Hiroyuki Ichikawa, Tsuyoshi Kouchi
  • Patent number: 9029873
    Abstract: The semiconductor device includes a SiC substrate; an aluminum nitride layer provided on the substrate and having an island-shaped pattern consisting of plural islands: a channel layer provided on the AlN layer and comprising a nitride semiconductor; an electron supplying layer provided on the channel layer and having a band gap larger than that of the channel layer; and a gate, source and drain electrodes on the electron supply layer. The AlN layer has an area-averaged circularity Y/X of greater than 0.2. Y is a sum of values obtained by multiplying circularities of the plural islands by areas of the plural islands respectively, X is a sum of the areas of the plural islands. The circularity are calculated by a formula of (4?×area)/(length of periphery)2 where the area and the length of periphery are an area and a length of periphery of each island.
    Type: Grant
    Filed: March 5, 2014
    Date of Patent: May 12, 2015
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Ken Nakata, Keiichi Yui, Tsuyoshi Kouchi, Isao Makabe, Hiroyuki Ichikawa
  • Patent number: 8993416
    Abstract: A method of manufacturing a semiconductor device includes growing a first GaN layer on a SiC substrate, and forming a second GaN layer on the first GaN layer, the second GaN layer being grown under such conditions that a ratio of a vertical growth rate to a horizontal growth rate is lower than that in the growth of the first GaN layer.
    Type: Grant
    Filed: July 29, 2011
    Date of Patent: March 31, 2015
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Keiichi Yui, Ken Nakata, Isao Makabe, Hiroyuki Ichikawa
  • Publication number: 20150009790
    Abstract: [PROBLEM] To provide an object lens such that the degradation of the optical properties of the object lens due to temperature change can be minimized, and a light pickup device using the same. [SOLUTION] An object lens R has lens surfaces R1, R2 which converges BD light, DVD light and CD light with prescribed numerical apertures into spots, and an antireflective film R1a formed on the lens surface R1. The lens surface R1 includes a BD exclusive region A1, a two-wavelength common region A2, and a three-wavelength common region A3. Diffractive structures P1, P2 and P3 are formed respectively for the BD exclusive region A1, the two-wavelength common region A2 and the three-wavelength common region A3. The antireflective film R1a is designed such that the transmittance for BD light is largest in the range of the two-wavelength common region A2.
    Type: Application
    Filed: December 18, 2012
    Publication date: January 8, 2015
    Inventors: Mitsuru Ito, Yuki Koshimizu, Yoshitoshi Oyamada, Hiroyuki Ichikawa
  • Publication number: 20140367547
    Abstract: An engine mount for use in a power unit vibration damping support structure configured to be mounted on a transmission side in a state without a distributed support load of a weight of the power unit being applied, the engine mount including: an inner shaft member; an outer tube member arranged separated to an outer circumference side of the inner shaft member; and a main rubber elastic body fixed to the inner shaft member while being attached to the outer tube member non-adhesively such that the inner shaft member and the outer tube member are elastically connected by the main rubber elastic body, wherein the outer tube member is configured to be attached to the power unit, and the inner shaft member is configured to be attached to a vehicle body.
    Type: Application
    Filed: April 14, 2014
    Publication date: December 18, 2014
    Applicants: TOKAI RUBBER INDUSTRIES, LTD., TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Masahiro OHNISHI, Akio SAIKI, Takayoshi YASUDA, Hiroyuki ICHIKAWA, Nobuya YOSHIDA, Hiroshi MIYA
  • Publication number: 20140346530
    Abstract: A semiconductor device according to an embodiment of the present invention includes a SiC substrate, an AlN layer provided on the SiC substrate and having a maximum valley depth Rv of 5 nm or less in an upper surface, a channel layer provided on the AlN layer and composed of a nitride semiconductor, an electron supply layer provided on the channel layer and having a greater band gap than the channel layer, and a gate electrode, a source electrode and a drain electrode provided on the electron supply layer.
    Type: Application
    Filed: May 22, 2014
    Publication date: November 27, 2014
    Applicant: SUMITOMO ELECTRIC INDUSTIRES, LTD.
    Inventors: Ken NAKATA, Keiichi YUI, Hiroyuki ICHIKAWA, Isao MAKABE, Tsuyoshi KOUCHI
  • Publication number: 20140252377
    Abstract: The semiconductor device includes a SiC substrate; an aluminum nitride layer provided on the substrate and having an island-shaped pattern consisting of plural islands: a channel layer provided on the AlN layer and comprising a nitride semiconductor; an electron supplying layer provided on the channel layer and having a band gap larger than that of the channel layer; and a gate, source and drain electrodes on the electron supply layer. The AlN layer has an area-averaged circularity Y/X of greater than 0.2. Y is a sum of values obtained by multiplying circularities of the plural islands by areas of the plural islands respectively, X is a sum of the areas of the plural islands. The circularity are calculated by a formula of (4?×area)/(length of periphery)2 where the area and the length of periphery are an area and a length of periphery of each island.
    Type: Application
    Filed: March 5, 2014
    Publication date: September 11, 2014
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Ken NAKATA, Keiichi YUI, Tsuyoshi KOUCHI, Isao MAKABE, Hiroyuki ICHIKAWA
  • Publication number: 20140246558
    Abstract: A vibration damping device including a first mounting member arranged on a lower side of a second mounting member, the first and second mounting members being elastically connected by a main rubber elastic body, and an outer bracket arranged on the lower side of the second mounting member. A coupling part is constituted by engagement between a bottom edge of the second mounting member and a top edge of the outer bracket, and the second mounting member is configured to be attached to a vibration source via the outer bracket. The outer bracket is arranged in opposition to the first mounting member in an axis-perpendicular direction, and an axis-perpendicular stopper member that regulates relative displacement between the first and second mounting members in the axis-perpendicular direction is constituted by contact between the first mounting member and the outer bracket.
    Type: Application
    Filed: May 13, 2014
    Publication date: September 4, 2014
    Applicant: TOKAI RUBBER INDUSTRIES, LTD.
    Inventors: Hiroyuki ICHIKAWA, Takayoshi YASUDA, Akio SAIKI
  • Publication number: 20140183563
    Abstract: A GaN device suppressing the instantaneous current reduction after the shut-off of a high frequency signal is disclosed. The GaN device provides, on a SiC substrate, an AlN layer, a GaN layer, and an AlGaN layer. The SiC substrate has an energy difference greater than 0.67 eV but less than 1.43 eV; the AlN layer has a thickness less than 50 nm; and the GaN layer has a thickness less than 1.
    Type: Application
    Filed: December 27, 2013
    Publication date: July 3, 2014
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Ken NAKATA, Keiichi YUI, Hiroyuki ICHIKAWA, Tsuyoshi KOUCHI
  • Publication number: 20140145383
    Abstract: A fluid-filled vibration damping device including a second orifice passage and a third orifice passage tuned to a lower frequency than the second orifice passage, and an actuator including an output portion facing openings of the second and third orifice passages on a side of an equilibrium chamber via a flexible film. The flexible film obstructs the openings of the second and third orifice passages when the output portion comes into contact against a partition member so that the third orifice passage is blocked while the second orifice passage is substantially placed in communication owing to a center recess of the output portion permitting deformation of the flexible film. Meanwhile, the flexible film is separated from the openings of the second and third orifice passages when the output portion is separated from the partition member so that the two orifice passages are placed in communication.
    Type: Application
    Filed: October 22, 2013
    Publication date: May 29, 2014
    Inventors: Takayoshi YASUDA, Hiroyuki ICHIKAWA, Akio SAIKI
  • Patent number: 8573570
    Abstract: A fluid-filled vibration damping device including: a pressure-receiving chamber and an equilibrium chamber disposed on either side of a partition plate, while being connected through a first orifice passage; a moveable film arranged to either a pressure-receiving chamber side or an equilibrium chamber side of the partition plate while being spaced away therefrom to define therebetween an intermediate chamber; a second orifice passage connecting the intermediate chamber and one of the pressure-receiving and the equilibrium chambers while being tuned to higher frequency than the first orifice passage; and a flow straightening plate arranged in opposition to the moveable film at least at one of the intermediate chamber side and an opposite side thereof, the flow straightening plate having a plurality of flow straightening apertures opening towards the moveable film and furnished with a flow limiting member.
    Type: Grant
    Filed: February 18, 2010
    Date of Patent: November 5, 2013
    Assignees: Tokai Rubber Industries, Ltd., Toyota Jidosha Kabushiki Kaisha
    Inventors: Hiroyuki Ichikawa, Yuichi Ogawa, Naoki Furumachi, Katsuhiro Sakurai, Nobuya Yoshida