Patents by Inventor Takui Sakaguchi

Takui 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).

  • Publication number: 20230361210
    Abstract: A semiconductor device includes a semiconductor layer having a first surface and a second surface, a unit cell including a diode region of a first conductivity type formed in a surface layer portion of the first surface of the semiconductor layer, a well region of a second conductivity type formed in the surface layer portion of the first surface of the semiconductor layer along a peripheral edge of the diode region, and a first conductivity type region formed in a surface layer portion of the well region, a gate electrode layer facing the well region and the first conductivity type region through a gate insulating layer and a first surface electrode covering the diode region and the first conductivity type region on the first surface of the semiconductor layer, and forming a Schottky junction with the diode region and an ohmic junction with the first conductivity type region.
    Type: Application
    Filed: July 17, 2023
    Publication date: November 9, 2023
    Applicant: ROHM CO., LTD.
    Inventors: Takui SAKAGUCHI, Masatoshi AKETA, Yuki NAKANO
  • Patent number: 11749749
    Abstract: A semiconductor device includes a semiconductor layer having a first main surface on one side and a second main surface on the other side, a unit cell including a diode region of a first conductivity type formed in a surface layer portion of the first main surface of the semiconductor layer, a well region of a second conductivity type formed in the surface layer portion of the first main surface of the semiconductor layer along a peripheral edge of the diode region, and a first conductivity type region formed in a surface layer portion of the well region, a gate electrode layer facing the well region and the first conductivity type region through a gate insulating layer and a first main surface electrode covering the diode region and the first conductivity type region on the first main surface of the semiconductor layer, and forming a Schottky junction with the diode region and an ohmic junction with the first conductivity type region.
    Type: Grant
    Filed: July 9, 2021
    Date of Patent: September 5, 2023
    Assignee: ROHM CO., LTD.
    Inventors: Takui Sakaguchi, Masatoshi Aketa, Yuki Nakano
  • Publication number: 20210336049
    Abstract: A semiconductor device includes a semiconductor layer having a first main surface on one side and a second main surface on the other side, a unit cell including a diode region of a first conductivity type formed in a surface layer portion of the first main surface of the semiconductor layer, a well region of a second conductivity type formed in the surface layer portion of the first main surface of the semiconductor layer along a peripheral edge of the diode region, and a first conductivity type region formed in a surface layer portion of the well region, a gate electrode layer facing the well region and the first conductivity type region through a gate insulating layer and a first main surface electrode covering the diode region and the first conductivity type region on the first main surface of the semiconductor layer, and forming a Schottky junction with the diode region and an ohmic junction with the first conductivity type region.
    Type: Application
    Filed: July 9, 2021
    Publication date: October 28, 2021
    Inventors: Takui SAKAGUCHI, Masatoshi AKETA, Yuki NAKANO
  • Publication number: 20210305369
    Abstract: An SiC semiconductor device includes an SiC semiconductor layer having a first main surface and a second main surface, a gate electrode embedded in a trench with a gate insulating layer, a source region of a first conductivity type formed in a side of the trench in a surface layer portion of the first main surface, a body region of a second conductivity type formed in a region at the second main surface side with respect to the source region in the surface layer portion of the first main surface, a drift region of the first conductivity type formed in a region at the second main surface side in the SiC semiconductor layer, and a contact region of the second conductivity type having an impurity concentration of not more than 1.0×1020 cm?3 and formed in the surface layer portion of the first main surface.
    Type: Application
    Filed: August 5, 2019
    Publication date: September 30, 2021
    Inventors: Yuki NAKANO, Masatoshi AKETA, Takui SAKAGUCHI, Yuichiro NANEN
  • Patent number: 11088272
    Abstract: A semiconductor device includes a semiconductor layer having a first main surface on one side and a second main surface on the other side, a unit cell including a diode region of a first conductivity type formed in a surface layer portion of the first main surface of the semiconductor layer, a well region of a second conductivity type formed in the surface layer portion of the first main surface of the semiconductor layer along a peripheral edge of the diode region, and a first conductivity type region formed in a surface layer portion of the well region, a gate electrode layer facing the well region and the first conductivity type region through a gate insulating layer and a first main surface electrode covering the diode region and the first conductivity type region on the first main surface of the semiconductor layer, and forming a Schottky junction with the diode region and an ohmic junction with the first conductivity type region.
    Type: Grant
    Filed: January 25, 2018
    Date of Patent: August 10, 2021
    Assignee: ROHM CO., LTD.
    Inventors: Takui Sakaguchi, Masatoshi Aketa, Yuki Nakano
  • Publication number: 20210083094
    Abstract: A semiconductor device includes a semiconductor layer having a first main surface on one side and a second main surface on the other side, a unit cell including a diode region of a first conductivity type formed in a surface layer portion of the first main surface of the semiconductor layer, a well region of a second conductivity type formed in the surface layer portion of the first main surface of the semiconductor layer along a peripheral edge of the diode region, and a first conductivity type region formed in a surface layer portion of the well region, a gate electrode layer facing the well region and the first conductivity type region through a gate insulating layer and a first main surface electrode covering the diode region and the first conductivity type region on the first main surface of the semiconductor layer, and forming a Schottky junction with the diode region and an ohmic junction with the first conductivity type region.
    Type: Application
    Filed: January 25, 2018
    Publication date: March 18, 2021
    Inventors: Takui SAKAGUCHI, Masatoshi AKETA, Yuki NAKANO
  • Patent number: 10804388
    Abstract: A semiconductor device 1 includes a trench gate structure 6 formed in a surface layer portion of a first principal surface of a semiconductor layer. A source region 10 and a well region 11 are formed in a surface layer portion of the first principal surface of the semiconductor layer at a side of the trench gate structure 6. The well region 11 is formed in a region at a side of the second principal surface of the semiconductor layer with respect to the source region 10. A channel is formed along the trench gate structure 6 in a portion of the well region 11. A multilayer region 22 is formed in a region between the trench gate structure 6 and the source region 10 in the semiconductor layer. The multilayer region 22 has a p type impurity region 20 formed in the surface layer portion of the first principal surface of the semiconductor layer and an n type impurity region 21 formed in a side of the second principal surface of the semiconductor layer with respect to the second conductivity type impurity region 20.
    Type: Grant
    Filed: January 16, 2017
    Date of Patent: October 13, 2020
    Assignee: ROHM CO., LTD.
    Inventors: Minoru Nakagawa, Seigo Mori, Takui Sakaguchi, Masatoshi Aketa, Yuki Nakano
  • Publication number: 20200098910
    Abstract: A semiconductor device 1 includes a trench gate structure 6 formed in a surface layer portion of a first principal surface of a semiconductor layer. A source region 10 and a well region 11 are formed in a surface layer portion of the first principal surface of the semiconductor layer at a side of the trench gate structure 6. The well region 11 is formed in a region at a side of the second principal surface of the semiconductor layer with respect to the source region 10. A channel is formed along the trench gate structure 6 in a portion of the well region 11. A multilayer region 22 is formed in a region between the trench gate structure 6 and the source region 10 in the semiconductor layer. The multilayer region 22 has a p type impurity region 20 formed in the surface layer portion of the first principal surface of the semiconductor layer and an n type impurity region 21 formed in a side of the second principal surface of the semiconductor layer with respect to the second conductivity type impurity region 20.
    Type: Application
    Filed: January 16, 2017
    Publication date: March 26, 2020
    Inventors: Minoru NAKAGAWA, Seigo MORI, Takui SAKAGUCHI, Masatoshi AKETA, Yuki NAKANO
  • Patent number: 9444222
    Abstract: The 2D-PC surface emitting laser includes: a PC layer; and a lattice point for forming resonant-state arranged in the photonic crystal layer, and configured so that a light wave in a band edge in photonic band structure in the PC layer is diffracted in a plane of the PC layer, and is diffracted in a surface vertical direction of the PC layer. The perturbation for diffracting the light wave in the surface vertical direction of the PC layer is applied to the lattice point for forming resonant-state. The term “perturbation” means that modulation is periodically applied to the lattice point for forming resonant-state. For example, the periodic modulation may be refractive index modulation, hole-diameter modulation, or hole-depth modulation.
    Type: Grant
    Filed: January 7, 2014
    Date of Patent: September 13, 2016
    Assignee: ROHM CO., LTD.
    Inventors: Takui Sakaguchi, Seita Iwahashi, Eiji Miyai, Wataru Kunishi, Dai Onishi, Yoshikatsu Miura
  • Publication number: 20150372452
    Abstract: A two-dimensional photonic crystal laser according to the present invention includes a two-dimensional photonic crystal layer 15 having a base body made of Al?Ga1-?As (0<?<1) or (Al?Ga1-?)?In1-?P (0<=?<1, 0<?<1) with modified refractive index areas (air holes) 151 periodically arranged therein and an epitaxial growth layer 16 created on the two-dimensional photonic crystal layer 15 by an epitaxial method. Since Al?Ga1-?As and (Al?Ga1-?)?In1-?P are solid even at high temperatures, the air holes 151 will not be deformed in the process of creating the epitaxial growth layer 16, so that the performance of the two-dimensional photonic crystal layer 15 as a resonator can be maintained at high levels.
    Type: Application
    Filed: July 23, 2015
    Publication date: December 24, 2015
    Inventors: Susumu NODA, Takui SAKAGUCHI, Kazuya NAGASE, Wataru KUNISHI, Eiji MIYAI, Yoshikatsu MIURA, Dai OHNISHI
  • Patent number: 9130348
    Abstract: A two-dimensional photonic crystal laser according to the present invention includes a two-dimensional photonic crystal layer 15 having a base body made of Al?Ga1-?As (0<?<1) or (Al?Ga1-?)?In1-?P (0<=?<1, 0<?<1) with modified refractive index areas (air holes) 151 periodically arranged therein and an epitaxial growth layer 16 created on the two-dimensional photonic crystal layer 15 by an epitaxial method. Since Al?Ga1-?As and (Al?Ga1-?)?In1-?P are solid even at high temperatures, the air holes 151 will not be deformed in the process of creating the epitaxial growth layer 16, so that the performance of the two-dimensional photonic crystal layer 15 as a resonator can be maintained at high levels.
    Type: Grant
    Filed: July 28, 2011
    Date of Patent: September 8, 2015
    Assignees: KYOTO UNIVERSITY, ROHM CO., LTD.
    Inventors: Susumu Noda, Takui Sakaguchi, Kazuya Nagase, Wataru Kunishi, Eiji Miyai, Yoshikatsu Miura, Dai Ohnishi
  • Publication number: 20140348195
    Abstract: The 2D-PC vertical cavity surface emitting laser includes: a PC layer; and a lattice point for forming resonant-state arranged in the photonic crystal layer, and configured so that a light wave in a band edge in photonic band structure in the PC layer is diffracted in a plane of the PC layer, and is diffracted in a surface vertical direction of the PC layer. The perturbation for diffracting the light wave in the surface vertical direction of the PC layer is applied to the lattice point for forming resonant-state. The term “perturbation” means that modulation is periodically applied to the lattice point for forming resonant-state. For example, the periodic modulation may be refractive index modulation, hole-diameter modulation, or hole-depth modulation.
    Type: Application
    Filed: January 7, 2014
    Publication date: November 27, 2014
    Applicant: ROHM CO., LTD.
    Inventors: Takui SAKAGUCHI, Seita IWAHASHI, Eiji MIYAI, Wataru KUNISHI, Dai ONISHI, Yoshikatsu MIURA
  • Patent number: 8619830
    Abstract: A photonic crystal surface emission laser includes an active layer, and a photonic crystal layer made of a plate-shaped slab provided with modified refractive index area having a refractive index different from that of the slab, the modified refractive index areas being arranged on each of the lattice points of a first rhombic-like lattice and a second rhombic-like lattice in which both diagonals are mutually parallel and only one diagonal is of a different length, wherein ax1, ax2, ay, and n satisfy the following inequality: ? 1 a x ? ? 1 - 1 a x ? ? 2 ? ( 1 a x ? ? 1 + 1 a x ? ? 2 ) 2 + ( 2 a y ) 2 ? 1 n .
    Type: Grant
    Filed: August 10, 2012
    Date of Patent: December 31, 2013
    Assignees: Kyoto University, Rohm Co., Ltd.
    Inventors: Susumu Noda, Seita Iwahashi, Toshiyuki Nobuoka, Takui Sakaguchi, Eiji Miyai, Wataru Kunishi, Dai Ohnishi, Kazuya Nagase, Yoshikatsu Miura
  • Publication number: 20130039375
    Abstract: A photonic crystal surface emission laser includes an active layer, and a photonic crystal layer made of a plate-shaped slab provided with modified refractive index area having a refractive index different from that of the slab, the modified refractive index areas being arranged on each of the lattice points of a first rhombic-like lattice and a second rhombic-like lattice in which both diagonals are mutually parallel and only one diagonal is of a different length, wherein ax1, ax2, ay, and n satisfy the following inequality: ? 1 a x ? ? 1 - 1 a x ? ? 2 ? ( 1 a x ? ? 1 + 1 a x ? ? 2 ) 2 + ( 2 a y ) 2 ? 1 n .
    Type: Application
    Filed: August 10, 2012
    Publication date: February 14, 2013
    Applicants: ROHM CO., LTD., KYOTO UNIVERSITY
    Inventors: Susumu NODA, Seita IWAHASHI, Toshiyuki NOBUOKA, Takui SAKAGUCHI, Eiji MIYAI, Wataru KUNISHI, Dai OHNISHI, Kazuya NAGASE, Yoshikatsu MIURA
  • Patent number: 8236421
    Abstract: In a metallic structure including a metallic nano-chain with plasmon resonance absorption, a metallic nanoparticle forming the metallic nano-chain is formed in a circular, triangle, or rhomboid shape. The wavelength selectivity can be increased also by forming a closed region by mutually linking all of metallic nanoparticles that are mutually linked with bottlenecks. In a photodetector, a photodetection unit including a current detection probe, a nano-chain unit, and a current detection probe is arranged on a substrate. The nano-chain unit is a metallic structure with plasmon resonance absorption, where metallic nanoparticles are mutually linked with bottlenecks. Each current detection probe has a corner whose tip is formed with a predetermined angle, and this corner is arranged to face the tip of the nano-chain unit, i.e., a corner of the metallic nanoparticle. Photodetection with high wavelength selectivity is performed based on a change in the initial voltage of the current-voltage characteristic.
    Type: Grant
    Filed: July 8, 2011
    Date of Patent: August 7, 2012
    Assignees: Rohm Co., Ltd., National University Corporation Hokkaido University
    Inventors: Kosei Ueno, Hiroaki Misawa, Dai Ohnishi, Takui Sakaguchi, Yoichi Mugino
  • Publication number: 20120027038
    Abstract: A two-dimensional photonic crystal laser according to the present invention includes a two-dimensional photonic crystal layer 15 having a base body made of Al?Ga1-?As (0<?<1) or (Al?Ga1-?)?In1-?P (0<=?<1, 0<?<1) with modified refractive index areas (air holes) 151 periodically arranged therein and an epitaxial growth layer 16 created on the two-dimensional photonic crystal layer 15 by an epitaxial method. Since Al?Ga1-?As and (Al?Ga1-?)?In1-?P are solid even at high temperatures, the air holes 151 will not be deformed in the process of creating the epitaxial growth layer 16, so that the performance of the two-dimensional photonic crystal layer 15 as a resonator can be maintained at high levels.
    Type: Application
    Filed: July 28, 2011
    Publication date: February 2, 2012
    Applicants: ROHM CO., LTD., KYOTO UNIVERSITY
    Inventors: Susumu Noda, Takui Sakaguchi, Kazuya Nagase, Wataru Kunishi, Eiji Miyai, Yoshikatsu Miura, Dai Ohnishi
  • Patent number: 8088484
    Abstract: In a metallic structure including a metallic nano-chain with plasmon resonance absorption, a metallic nanoparticle forming the metallic nano-chain is formed in a circular, triangle, or rhomboid shape. The wavelength selectivity can be increased also by forming a closed region by mutually linking all of metallic nanoparticles that are mutually linked with bottlenecks. In a photodetector, a photodetection unit including a current detection probe, a nano-chain unit, and a current detection probe is arranged on a substrate. The nano-chain unit is a metallic structure with plasmon resonance absorption, where metallic nanoparticles are mutually linked with bottlenecks. Each current detection probe has a corner whose tip is formed with a predetermined angle, and this corner is arranged to face the tip of the nano-chain unit, i.e., a corner of the metallic nanoparticle. Photodetection with high wavelength selectivity is performed based on a change in the initial voltage of the current-voltage characteristic.
    Type: Grant
    Filed: September 2, 2008
    Date of Patent: January 3, 2012
    Assignees: Rohm Co. Ltd., National University Corporation Hokkaido University
    Inventors: Kosei Ueno, Hiroaki Misawa, Dai Ohnishi, Takui Sakaguchi, Yoichi Mugino
  • Publication number: 20110266414
    Abstract: In a metallic structure including a metallic nano-chain with plasmon resonance absorption, a metallic nanoparticle forming the metallic nano-chain is formed in a circular, triangle, or rhomboid shape. The wavelength selectivity can be increased also by forming a closed region by mutually linking all of metallic nanoparticles that are mutually linked with bottlenecks. In a photodetector, a photodetection unit including a current detection probe, a nano-chain unit, and a current detection probe is arranged on a substrate. The nano-chain unit is a metallic structure with plasmon resonance absorption, where metallic nanoparticles are mutually linked with bottlenecks. Each current detection probe has a corner whose tip is formed with a predetermined angle, and this corner is arranged to face the tip of the nano-chain unit, i.e., a corner of the metallic nanoparticle. Photodetection with high wavelength selectivity is performed based on a change in the initial voltage of the current-voltage characteristic.
    Type: Application
    Filed: July 8, 2011
    Publication date: November 3, 2011
    Applicants: National University Corporation Hokkaido University, ROHM CO., LTD.
    Inventors: Kosei UENO, Hiroaki Misawa, Dai Ohnishi, Takui Sakaguchi, Yoichi Mugino
  • Patent number: 8047713
    Abstract: Provided is a plasmon resonance detector that can detect temperature change in optical devices, in which the metal structure having plasmon resonance absorption is used for the optical devices. A diode formed of a conductive substrate, an n-type semiconductor layer, an i-type semiconductor layer, a p-type semiconductor layer, an n electrode (negative electrode), a p electrode (positive electrode), an insulating film, or the like is used as a semiconductor device whose resistance value changes in accordance with temperature change. A nanochain formed by connecting a plurality of metal nanoparticles is disposed on this diode. When the nanochain is irradiated with light, the nanochain generates heat. The heat generated in the nanochain is conducted to the diode. The resistance value of the diode changes in accordance with temperature change, and thus this change is read, a temperature or an amount of heat generation of the nanochain is measured, and existence and strength of the plasmon resonance are detected.
    Type: Grant
    Filed: December 22, 2008
    Date of Patent: November 1, 2011
    Assignee: Rohm Co., Ltd.
    Inventors: Kosei Ueno, Hiroaki Misawa, Dai Ohnishi, Takui Sakaguchi, Yoichi Mugino
  • Publication number: 20100067016
    Abstract: Provided is a plasmon resonance detector that can detect temperature change in optical devices, in which the metal structure having plasmon resonance absorption is used for the optical devices. A diode formed of a conductive substrate, an n-type semiconductor layer, an i-type semiconductor layer, a p-type semiconductor layer, an n electrode (negative electrode), a p electrode (positive electrode), an insulating film, or the like is used as a semiconductor device whose resistance value changes in accordance with temperature change. A nanochain formed by connecting a plurality of metal nanoparticles is disposed on this diode. When the nanochain is irradiated with light, the nanochain generates heat. The heat generated in the nanochain is conducted to the diode. The resistance value of the diode changes in accordance with temperature change, and thus this change is read, a temperature or an amount of heat generation of the nanochain is measured, and existence and strength of the plasmon resonance are detected.
    Type: Application
    Filed: December 22, 2008
    Publication date: March 18, 2010
    Applicants: ROHM CO., LTD., National University Corporation Hokkaido University
    Inventors: Kosei UENO, Hiroaki MISAWA, Dai OHNISHI, Takui SAKAGUCHI, Yoichi MUGINO