Patents by Inventor Norikazu Ito

Norikazu Ito 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: 20220102543
    Abstract: A nitride semiconductor device 1 includes a first nitride semiconductor layer 4 that constitutes an electron transit layer, a second nitride semiconductor layer 5 that is formed on the first nitride semiconductor layer, is larger in bandgap than the first nitride semiconductor layer, and constitutes an electron supply layer, and a gate portion 20 that is formed on the second nitride semiconductor layer. The gate portion 20 includes a first semiconductor gate layer 21 of a ridge shape that is disposed on the second nitride semiconductor layer 5 and is constituted of a nitride semiconductor containing an acceptor type impurity, a second semiconductor gate layer 22 that is formed on the first semiconductor gate layer 21 and is constituted of a nitride semiconductor with a larger bandgap than the first semiconductor gate layer 21, and a gate electrode 23 that is formed on the second semiconductor gate layer 22 and is in Schottky junction with the second semiconductor gate layer 22.
    Type: Application
    Filed: January 15, 2020
    Publication date: March 31, 2022
    Inventors: Hirotaka OTAKE, Shinya TAKADO, Taketoshi TANAKA, Norikazu ITO
  • Publication number: 20220094326
    Abstract: A piezoelectric element includes a single crystal piezoelectric film, wherein the single crystal piezoelectric film includes an aluminum nitride film and wherein a full width at half maximum at (002) diffraction peak of the aluminum nitride film is smaller than 1.00 degree.
    Type: Application
    Filed: September 14, 2021
    Publication date: March 24, 2022
    Applicant: ROHM CO., LTD.
    Inventors: Noriyuki SHIMOJI, Tomohiro DATE, Norikazu ITO
  • Patent number: 11081617
    Abstract: A solar battery device includes a semiconductor substrate and a covering part. The semiconductor substrate has a first semiconductor region and a second semiconductor region. The first semiconductor region is a first-conductivity-type semiconductor region located on a first surface of the semiconductor substrate. The second semiconductor region is a second-conductivity-type semiconductor region different from the first-conductivity-type and located on a second surface opposite from the first surface. The covering part is located on the first surface of the semiconductor substrate. The covering part has a laminated portion in which a plurality of layers including a passivation layer and an antireflection layer are present in a laminated state. In the laminated portion, the passivation layer includes a region in which a thickness decreases from an outer peripheral portion toward a central part of the first surface.
    Type: Grant
    Filed: October 22, 2019
    Date of Patent: August 3, 2021
    Assignee: KYOCERA CORPORATION
    Inventors: Norikazu Ito, Kenji Fukuchi
  • Publication number: 20210217886
    Abstract: A nitride semiconductor device includes an electron transit layer (103) that is formed of a nitride semiconductor, an electron supply layer (104) that is formed on the electron transit layer (103), that is formed of a nitride semiconductor whose composition is different from the electron transit layer (103) and that has a recess (109) which reaches the electron transit layer (103) from a surface, a thermal oxide film (111) that is formed on the surface of the electron transit layer (103) exposed within the recess (109), a gate insulating film (110) that is embedded within the recess (109) so as to be in contact with the thermal oxide film (111), a gate electrode (108) that is formed on the gate insulating film (110) and that is opposite to the electron transit layer (103) across the thermal oxide film (111) and the gate insulating film (110), and a source electrode (106) and a drain electrode (107) that are provided on the electron supply layer (104) at an interval such that the gate electrode (108) intervene
    Type: Application
    Filed: March 25, 2021
    Publication date: July 15, 2021
    Inventors: Kenji YAMAMOTO, Tetsuya FUJIWARA, Minoru AKUTSU, Ken NAKAHARA, Norikazu ITO
  • Patent number: 11031900
    Abstract: A motor drive apparatus includes: inverter modules equivalent in number to phases of a motor; and a control unit that generates a PWM signal for driving the inverter modules by using PWM. Each of the inverter modules includes: a plurality of pairs of switching elements, each pair of switching elements including two switching elements connected in series; a drive circuit; and a protection circuit. The plurality of pairs of switching elements is connected in parallel, and power GNDs that are reference terminals of the plurality of pairs of switching elements, a control GND that is a reference terminal of the drive circuit, and a terminal for overcurrent fault input in the protection circuit are independently exposed to the outside. The power GNDs and the control GND are connected to a single point on a printed circuit board by a wiring pattern.
    Type: Grant
    Filed: April 27, 2016
    Date of Patent: June 8, 2021
    Assignee: Mitsubishi Electric Corporation
    Inventors: Norikazu Ito, Shigeo Umehara, Katsuhiko Saito, Katsuyuki Amano, Masahiro Fukuda
  • Patent number: 10991818
    Abstract: A nitride semiconductor device includes an electron transit layer (103) that is formed of a nitride semiconductor, an electron supply layer (104) that is formed on the electron transit layer (103), that is formed of a nitride semiconductor whose composition is different from the electron transit layer (103) and that has a recess (109) which reaches the electron transit layer (103) from a surface, a thermal oxide film (111) that is formed on the surface of the electron transit layer (103) exposed within the recess (109), a gate insulating film (110) that is embedded within the recess (109) so as to be in contact with the thermal oxide film (111), a gate electrode (108) that is formed on the gate insulating film (110) and that is opposite to the electron transit layer (103) across the thermal oxide film (111) and the gate insulating film (110), and a source electrode (106) and a drain electrode (107) that are provided on the electron supply layer (104) at an interval such that the gate electrode (108) intervene
    Type: Grant
    Filed: May 12, 2020
    Date of Patent: April 27, 2021
    Assignee: ROHM CO., LTD.
    Inventors: Kenji Yamamoto, Tetsuya Fujiwara, Minoru Akutsu, Ken Nakahara, Norikazu Ito
  • Publication number: 20200365694
    Abstract: A nitride semiconductor device includes a first impurity layer made of an Al1-XGaXN (0<X?1) based material and containing a first impurity with which a depth of an acceptor level from a valence band (ET-EV) is made not less than 0.3 eV but less than 0.6 eV, an electron transit layer formed on the first impurity layer, an electron supply layer formed on the electron transit layer, agate electrode formed on the electron transit layer, and a source electrode and a drain electrode formed such that the source electrode and the drain electrode sandwich the gate electrode and electrically connected to the electron supply layer.
    Type: Application
    Filed: December 21, 2018
    Publication date: November 19, 2020
    Inventors: Norikazu ITO, Taketoshi TANAKA, Ken NAKAHARA
  • Publication number: 20200273975
    Abstract: A nitride semiconductor device includes an electron transit layer (103) that is formed of a nitride semiconductor, an electron supply layer (104) that is formed on the electron transit layer (103), that is formed of a nitride semiconductor whose composition is different from the electron transit layer (103) and that has a recess (109) which reaches the electron transit layer (103) from a surface, a thermal oxide film (111) that is formed on the surface of the electron transit layer (103) exposed within the recess (109), a gate insulating film (110) that is embedded within the recess (109) so as to be in contact with the thermal oxide film (111), a gate electrode (108) that is formed on the gate insulating film (110) and that is opposite to the electron transit layer (103) across the thermal oxide film (111) and the gate insulating film (110), and a source electrode (106) and a drain electrode (107) that are provided on the electron supply layer (104) at an interval such that the gate electrode (108) intervene
    Type: Application
    Filed: May 12, 2020
    Publication date: August 27, 2020
    Inventors: Kenji YAMAMOTO, Tetsuya FUJIWARA, Minoru AKUTSU, Ken NAKAHARA, Norikazu ITO
  • Patent number: 10749414
    Abstract: A motor driving device that converts alternating-current power to direct-current power and drives a motor, the motor driving device including a printed circuit board having a first plate surface and a second plate surface, having an inverter module and an inverter module provided on the first plate surface, having a first power pattern provided on the second plate surface and connected to the inverter module, having a second power pattern provided on the second plate surface and connected to the inverter module, and having a jumper portion to connect the first power pattern and the second power pattern. A cross-sectional area of the jumper portion is larger than a cross-sectional area of the first power pattern or the second power pattern.
    Type: Grant
    Filed: April 27, 2016
    Date of Patent: August 18, 2020
    Assignee: Mitsubishi Electric Corporation
    Inventors: Norikazu Ito, Takuya Shimomugi, Masahiro Fukuda
  • Patent number: 10727312
    Abstract: A nitride semiconductor device includes: an electron transit layer including GaxIn1-xN (0<x?1); an electron supply layer formed on the electron transit layer and including AlyIn1-yN (0<y?1); a gate insulating film formed to pass through the electron supply layer to contact the electron transit layer; and a gate electrode facing the electron transit layer with the gate insulating film interposed therebetween, wherein, in the electron transit layer, a portion contacting the gate insulating film and a portion contacting the electron transit layer are flush with each other.
    Type: Grant
    Filed: May 23, 2019
    Date of Patent: July 28, 2020
    Assignee: ROHM CO., LTD.
    Inventors: Shinya Takado, Minoru Akutsu, Taketoshi Tanaka, Norikazu Ito
  • Patent number: 10686064
    Abstract: A nitride semiconductor device includes an electron transit layer (103) that is formed of a nitride semiconductor, an electron supply layer (104) that is formed on the electron transit layer (103), that is formed of a nitride semiconductor whose composition is different from the electron transit layer (103) and that has a recess (109) which reaches the electron transit layer (103) from a surface, a thermal oxide film (111) that is formed on the surface of the electron transit layer (103) exposed within the recess (109), a gate insulating film (110) that is embedded within the recess (109) so as to be in contact with the thermal oxide film (111), a gate electrode (108) that is formed on the gate insulating film (110) and that is opposite to the electron transit layer (103) across the thermal oxide film (111) and the gate insulating film (110), and a source electrode (106) and a drain electrode (107) that are provided on the electron supply layer (104) at an interval such that the gate electrode (108) intervene
    Type: Grant
    Filed: March 7, 2019
    Date of Patent: June 16, 2020
    Assignee: ROHM CO., LTD.
    Inventors: Kenji Yamamoto, Tetsuya Fujiwara, Minoru Akutsu, Ken Nakahara, Norikazu Ito
  • Patent number: 10658967
    Abstract: A motor drive apparatus driving a motor as a three-phase motor converting direct power into three-phase alternating power, includes: inverter modules equivalent in number to phases of the motor; and a control unit generating PWM signals used to drive the inverter modules with PWM. The inverter modules each include a plurality of switching element pairs connected in parallel, each of the switching element pairs including two switching elements connected in series.
    Type: Grant
    Filed: November 4, 2014
    Date of Patent: May 19, 2020
    Assignee: Mitsubishi Electric Corporation
    Inventors: Yosuke Shinomoto, Takuya Shimomugi, Norikazu Ito, Keisuke Uemura, Takashi Yamakawa
  • Publication number: 20200052149
    Abstract: A solar battery device includes a semiconductor substrate and a covering part. The semiconductor substrate has a first semiconductor region and a second semiconductor region. The first semiconductor region is a first-conductivity-type semiconductor region located on a first surface of the semiconductor substrate. The second semiconductor region is a second-conductivity-type semiconductor region different from the first-conductivity-type and located on a second surface opposite from the first surface. The covering part is located on the first surface of the semiconductor substrate. The covering part has a laminated portion in which a plurality of layers including a passivation layer and an antireflection layer are present in a laminated state. In the laminated portion, the passivation layer includes a region in which a thickness decreases from an outer peripheral portion toward a central part of the first surface.
    Type: Application
    Filed: October 22, 2019
    Publication date: February 13, 2020
    Inventors: Norikazu ITO, Kenji FUKUCHI
  • Patent number: 10530288
    Abstract: A motor drive apparatus which drives a motor includes inverter modules equal in number to phases of the motor. Each of the inverter modules includes a plurality of switching element pairs. Each of the switching element pairs is defined by two switching elements connected in series. In each of the inverter modules, the plurality of switching element pairs are connected in parallel, and each of resistance values of gate resistors connected to the switching elements is set for the corresponding switching element connected thereto.
    Type: Grant
    Filed: September 4, 2015
    Date of Patent: January 7, 2020
    Assignee: Mitsubishi Electric Corporation
    Inventors: Takuya Shimomugi, Yosuke Shinomoto, Katsuhiko Saito, Norikazu Ito
  • Publication number: 20190305649
    Abstract: A motor driving device that converts alternating-current power to direct-current power and drives a motor, the motor driving device including a printed circuit board having a first plate surface and a second plate surface, having an inverter module and an inverter module provided on the first plate surface, having a first power pattern provided on the second plate surface and connected to the inverter module, having a second power pattern provided on the second plate surface and connected to the inverter module, and having a jumper portion to connect the first power pattern and the second power pattern. A cross-sectional area of the jumper portion is larger than a cross-sectional area of the first power pattern or the second power pattern.
    Type: Application
    Filed: April 27, 2016
    Publication date: October 3, 2019
    Inventors: Norikazu ITO, Takuya SHIMOMUGI, Masahiro FUKUDA
  • Patent number: 10432131
    Abstract: There are provided the same number of inverter modules as the number of phases of a motor, and an inverter control unit that generates PWM signals used to drive the inverter modules in PWM. Three phase outputs from each of the inverter modules are coupled to form a phase output signal for one phase of the motor while capacitors are mounted between control GNDs of the inverter modules and power GNDs of the inverter modules. Consequently, even if a surge voltage is generated in a GND wiring at the time of a switching operation of switching elements in the inverter modules, the application of the surge voltage to the switching elements can be suppressed.
    Type: Grant
    Filed: April 27, 2016
    Date of Patent: October 1, 2019
    Assignee: Mitsubishi Electric Corporation
    Inventors: Norikazu Ito, Katsuhiko Saito, Shigeo Umehara, Katsuyuki Amano, Masahiro Fukuda
  • Publication number: 20190280637
    Abstract: A motor drive apparatus includes: inverter modules equivalent in number to phases of a motor; and a control unit that generates a PWM signal for driving the inverter modules by using PWM. Each of the inverter modules includes: a plurality of pairs of switching elements, each pair of switching elements including two switching elements connected in series; a drive circuit; and a protection circuit. The plurality of pairs of switching elements is connected in parallel, and power GNDs that are reference terminals of the plurality of pairs of switching elements, a control GND that is a reference terminal of the drive circuit, and a terminal for overcurrent fault input in the protection circuit are independently exposed to the outside. The power GNDs and the control GND are connected to a single point on a printed circuit board by a wiring pattern.
    Type: Application
    Filed: April 27, 2016
    Publication date: September 12, 2019
    Inventors: Norikazu ITO, Shigeo UMEHARA, Katsuhiko SAITO, Katsuyuki AMANO, Masahiro FUKUDA
  • Publication number: 20190280101
    Abstract: A nitride semiconductor device includes: an electron transit layer including GaxIn1-xN (0<x?1); an electron supply layer formed on the electron transit layer and including AlyIn1-yN (0<y?1); a gate insulating film formed to pass through the electron supply layer to contact the electron transit layer; and a gate electrode facing the electron transit layer with the gate insulating film interposed therebetween, wherein, in the electron transit layer, a portion contacting the gate insulating film and a portion contacting the electron transit layer are flush with each other.
    Type: Application
    Filed: May 23, 2019
    Publication date: September 12, 2019
    Applicant: ROHM CO., LTD.
    Inventors: Shinya TAKADO, Minoru AKUTSU, Taketoshi TANAKA, Norikazu ITO
  • Publication number: 20190207023
    Abstract: A nitride semiconductor device includes an electron transit layer (103) that is formed of a nitride semiconductor, an electron supply layer (104) that is formed on the electron transit layer (103), that is formed of a nitride semiconductor whose composition is different from the electron transit layer (103) and that has a recess (109) which reaches the electron transit layer (103) from a surface, a thermal oxide film (111) that is formed on the surface of the electron transit layer (103) exposed within the recess (109), a gate insulating film (110) that is embedded within the recess (109) so as to be in contact with the thermal oxide film (111), a gate electrode (108) that is formed on the gate insulating film (110) and that is opposite to the electron transit layer (103) across the thermal oxide film (111) and the gate insulating film (110), and a source electrode (106) and a drain electrode (107) that are provided on the electron supply layer (104) at an interval such that the gate electrode (108) intervene
    Type: Application
    Filed: March 7, 2019
    Publication date: July 4, 2019
    Inventors: Kenji YAMAMOTO, Tetsuya FUJIWARA, Minoru AKUTSU, Ken NAKAHARA, Norikazu ITO
  • Patent number: 10340360
    Abstract: A nitride semiconductor device includes: an electron transit layer including GaxIn1-xN (0<x?1); an electron supply layer formed on the electron transit layer and including AlyIn1-yN (0<y?1); a gate insulating film formed to pass through the electron supply layer to contact the electron transit layer; and a gate electrode facing the electron transit layer with the gate insulating film interposed therebetween, wherein, in the electron transit layer, a portion contacting the gate insulating film and a portion contacting the electron transit layer are flush with each other.
    Type: Grant
    Filed: February 26, 2018
    Date of Patent: July 2, 2019
    Assignee: ROHM CO., LTD.
    Inventors: Shinya Takado, Minoru Akutsu, Taketoshi Tanaka, Norikazu Ito