Patents by Inventor Tohru Kawai

Tohru Kawai 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).

  • Patent number: 10921515
    Abstract: A semiconductor device includes a substrate having a first surface and a second surface that have top and back relation, an insulating layer formed on the first surface of the substrate, and an optical waveguide formed on the insulating layer and formed of a semiconducting layer. A first opening is formed on the second surface of the substrate. The first opening overlaps the optical waveguide in plan view.
    Type: Grant
    Filed: November 12, 2019
    Date of Patent: February 16, 2021
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Yasutaka Nakashiba, Shinichi Watanuki, Tohru Kawai
  • Publication number: 20200192039
    Abstract: A semiconductor device includes a substrate having a first surface and a second surface that have top and back relation, an insulating layer formed on the first surface of the substrate, and an optical waveguide formed on the insulating layer and formed of a semiconducting layer. A first opening is formed on the second surface of the substrate. The first opening overlaps the optical waveguide in plan view.
    Type: Application
    Filed: November 12, 2019
    Publication date: June 18, 2020
    Inventors: Yasutaka NAKASHIBA, Shinichi WATANUKI, Tohru KAWAI
  • Patent number: 10475918
    Abstract: Performance of a semiconductor device is improved without increasing an area size of a semiconductor chip. For example, a source electrode of a power transistor and an upper electrode of a capacitor element have an overlapping portion. In other word, the upper electrode of the capacitor element is formed over the source electrode of the power transistor through a capacitor insulating film. That is, the power transistor and the capacitor element are arranged in a laminated manner in a thickness direction of the semiconductor chip. As a result, it becomes possible to add a capacitor element to be electrically coupled to the power transistor while suppressing an increase in planar size of the semiconductor chip.
    Type: Grant
    Filed: January 31, 2019
    Date of Patent: November 12, 2019
    Assignee: Renesas Electronics Corporation
    Inventors: Tohru Kawai, Yasutaka Nakashiba, Yutaka Akiyama
  • Patent number: 10416481
    Abstract: The performances of a semiconductor device are improved. The semiconductor device includes an insulation layer, an optical waveguide part formed over the insulation layer, and including a p type semiconductor region and an n type semiconductor region formed therein, and an interlayer insulation film formed over the insulation layer in such a manner as to cover the optical waveguide part. At the first portion of the optical waveguide part, in a cross sectional view perpendicular to the direction of extension of the optical waveguide part, the n type semiconductor region is arranged at the central part of the optical waveguide part, and the p type semiconductor region is arranged in such a manner as to surround the entire circumference of the n type semiconductor region.
    Type: Grant
    Filed: November 6, 2018
    Date of Patent: September 17, 2019
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Tohru Kawai, Shinichi Watanuki, Yasutaka Nakashiba
  • Publication number: 20190196231
    Abstract: The performances of a semiconductor device are improved. The semiconductor device includes an insulation layer, an optical waveguide part formed over the insulation layer, and including a p type semiconductor region and an n type semiconductor region formed therein, and an interlayer insulation film formed over the insulation layer in such a manner as to cover the optical waveguide part. At the first portion of the optical waveguide part, in a cross sectional view perpendicular to the direction of extension of the optical waveguide part, the n type semiconductor region is arranged at the central part of the optical waveguide part, and the p type semiconductor region is arranged in such a manner as to surround the entire circumference of the n type semiconductor region.
    Type: Application
    Filed: November 6, 2018
    Publication date: June 27, 2019
    Inventors: Tohru KAWAI, Shinichi WATANUKI, Yasutaka NAKASHIBA
  • Publication number: 20190165165
    Abstract: Performance of a semiconductor device is improved without increasing an area size of a semiconductor chip. For example, a source electrode of a power transistor and an upper electrode of a capacitor element have an overlapping portion. In other word, the upper electrode of the capacitor element is formed over the source electrode of the power transistor through a capacitor insulating film. That is, the power transistor and the capacitor element are arranged in a laminated manner in a thickness direction of the semiconductor chip. As a result, it becomes possible to add a capacitor element to be electrically coupled to the power transistor while suppressing an increase in planar size of the semiconductor chip.
    Type: Application
    Filed: January 31, 2019
    Publication date: May 30, 2019
    Inventors: Tohru KAWAI, Yasutaka NAKASHIBA, Yutaka AKIYAMA
  • Patent number: 10236371
    Abstract: Performance of a semiconductor device is improved without increasing an area size of a semiconductor chip. For example, a source electrode of a power transistor and an upper electrode of a capacitor element have an overlapping portion. In other word, the upper electrode of the capacitor element is formed over the source electrode of the power transistor through a capacitor insulating film. That is, the power transistor and the capacitor element are arranged in a laminated manner in a thickness direction of the semiconductor chip. As a result, it becomes possible to add a capacitor element to be electrically coupled to the power transistor while suppressing an increase in planar size of the semiconductor chip.
    Type: Grant
    Filed: January 11, 2017
    Date of Patent: March 19, 2019
    Assignee: Renesas Electronics Corporation
    Inventors: Tohru Kawai, Yasutaka Nakashiba, Yutaka Akiyama
  • Patent number: 10056298
    Abstract: A manufacturing method of a semiconductor device comprises a step of ion-implanting a P-type impurity at a first dose amount to form semiconductor regions that are low concentration semiconductor regions of a high breakdown voltage P-type transistor, and a step of ion-implanting a P-type impurity at a second dose amount to form P? semiconductor regions that are low concentration semiconductor regions of a low breakdown voltage P-type transistor and form a P-type impurity layer that is a resistance portion of a polysilicon resistor. The manufacturing method further comprises a resistance portion forming step in which a resistance portion of the polysilicon resistor is made thinner than terminal portions at both ends of the resistance portion, and the second dose amount is larger than the first dose amount.
    Type: Grant
    Filed: August 26, 2017
    Date of Patent: August 21, 2018
    Assignee: Renesas Electronics Corporation
    Inventor: Tohru Kawai
  • Patent number: 9941284
    Abstract: A semiconductor device aims to prevent a leak current from flowing between a well and a corner of an active region formed on an upper surface of another well in an SRAM. In a memory cell of the SRAM, a load MOSFET is formed. An end of an active region extending in y-direction is arranged to gradually go away from a p-well as it goes from a gate electrode G2 side to a gate electrode G4 side in such a manner that a distance in x-direction between the end of the active region and the p-well is larger than a shortest distance in the x-direction between the p-well and the active region.
    Type: Grant
    Filed: July 24, 2017
    Date of Patent: April 10, 2018
    Assignee: Renesas Electronics Corporation
    Inventors: Tohru Kawai, Masahiro Shimizu
  • Patent number: 9933568
    Abstract: Provided is an SOI substrate which has a substrate, an insulating layer formed over the substrate, and a semiconductor layer formed over the insulating layer. Optical waveguides are formed in the semiconductor layer of the SOI substrate. This substrate has a low resistance semiconductor layer and a high resistance semiconductor layer thereover. Further, wirings which are formed through insulating films are provided on the optical waveguides. In this manner, the low resistance semiconductor layer is arranged in the surface part of the substrate of the insulating films, thereby restraining an eddy current generated in the substrate due to an electric signal transmitted through the wirings.
    Type: Grant
    Filed: November 29, 2016
    Date of Patent: April 3, 2018
    Assignee: Renesas Electronics Corporation
    Inventors: Tohru Kawai, Yasutaka Nakashiba
  • Publication number: 20180090382
    Abstract: A manufacturing method of a semiconductor device comprises a step of ion-implanting a P-type impurity at a first dose amount to form semiconductor regions that are low concentration semiconductor regions of a high breakdown voltage P-type transistor, and a step of ion-implanting a P-type impurity at a second dose amount to form P? semiconductor regions that are low concentration semiconductor regions of a low breakdown voltage P-type transistor and form a P-type impurity layer that is a resistance portion of a polysilicon resistor. The manufacturing method further comprises a resistance portion forming step in which a resistance portion of the polysilicon resistor is made thinner than terminal portions at both ends of the resistance portion, and the second dose amount is larger than the first dose amount.
    Type: Application
    Filed: August 26, 2017
    Publication date: March 29, 2018
    Inventor: Tohru KAWAI
  • Publication number: 20170323890
    Abstract: A semiconductor device aims to prevent a leak current from flowing between a well and a corner of an active region formed on an upper surface of another well in an SRAM. In a memory cell of the SRAM, a load MOSFET is formed. An end of an active region extending in y-direction is arranged to gradually go away from a p-well as it goes from a gate electrode G2 side to a gate electrode G4 side in such a manner that a distance in x-direction between the end of the active region and the p-well is larger than a shortest distance in the x-direction between the p-well and the active region.
    Type: Application
    Filed: July 24, 2017
    Publication date: November 9, 2017
    Applicant: Renesas Electronics Corporation
    Inventors: Tohru KAWAI, Masahiro SHIMIZU
  • Patent number: 9748247
    Abstract: A semiconductor device aims to prevent a leak current from flowing between a well and a corner of an active region formed on an upper surface of another well in an SRAM. In a memory cell of the SRAM, a load MOSFET is formed. An end of an active region extending in y-direction is arranged to gradually go away from a p-well as it goes from a gate electrode G2 side to a gate electrode G4 side in such a manner that a distance in x-direction between the end of the active region and the p-well is larger than a shortest distance in the x-direction between the p-well and the active region.
    Type: Grant
    Filed: November 23, 2016
    Date of Patent: August 29, 2017
    Assignee: Renesas Electronics Corporation
    Inventors: Tohru Kawai, Masahiro Shimizu
  • Publication number: 20170170183
    Abstract: A semiconductor device aims to prevent a leak current from flowing between a well and a corner of an active region formed on an upper surface of another well in an SRAM. In a memory cell of the SRAM, a load MOSFET is formed. An end of an active region extending in y-direction is arranged to gradually go away from a p-well as it goes from a gate electrode G2 side to a gate electrode G4 side in such a manner that a distance in x-direction between the end of the active region and the p-well is larger than a shortest distance in the x-direction between the p-well and the active region.
    Type: Application
    Filed: November 23, 2016
    Publication date: June 15, 2017
    Applicant: Renesas Electronics Corporation
    Inventors: Tohru KAWAI, Masahiro SHIMIZU
  • Publication number: 20170153390
    Abstract: Provided is an SOI substrate which has a substrate, an insulating layer formed over the substrate, and a semiconductor layer formed over the insulating layer. Optical waveguides are formed in the semiconductor layer of the SOI substrate. This substrate has a low resistance semiconductor layer and a high resistance semiconductor layer thereover. Further, wirings which are formed through insulating films are provided on the optical waveguides. In this manner, the low resistance semiconductor layer is arranged in the surface part of the substrate of the insulating films, thereby restraining an eddy current generated in the substrate due to an electric signal transmitted through the wirings.
    Type: Application
    Filed: November 29, 2016
    Publication date: June 1, 2017
    Applicant: Renesas Electronics Corporation
    Inventors: Tohru KAWAI, Yasutaka NAKASHIBA
  • Publication number: 20170125581
    Abstract: Performance of a semiconductor device is improved without increasing an area size of a semiconductor chip. For example, a source electrode of a power transistor and an upper electrode of a capacitor element have an overlapping portion. In other word, the upper electrode of the capacitor element is formed over the source electrode of the power transistor through a capacitor insulating film. That is, the power transistor and the capacitor element are arranged in a laminated manner in a thickness direction of the semiconductor chip. As a result, it becomes possible to add a capacitor element to be electrically coupled to the power transistor while suppressing an increase in planar size of the semiconductor chip.
    Type: Application
    Filed: January 11, 2017
    Publication date: May 4, 2017
    Inventors: Tohru KAWAI, Yasutaka NAKASHIBA, Yutaka AKIYAMA
  • Patent number: 9564426
    Abstract: Performance of a semiconductor device is improved without increasing an area size of a semiconductor chip. For example, a source electrode of a power transistor and an upper electrode of a capacitor element have an overlapping portion. In other word, the upper electrode of the capacitor element is formed over the source electrode of the power transistor through a capacitor insulating film. That is, the power transistor and the capacitor element are arranged in a laminated manner in a thickness direction of the semiconductor chip. As a result, it becomes possible to add a capacitor element to be electrically coupled to the power transistor while suppressing an increase in planar size of the semiconductor chip.
    Type: Grant
    Filed: November 4, 2015
    Date of Patent: February 7, 2017
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Tohru Kawai, Yasutaka Nakashiba, Yutaka Akiyama
  • Publication number: 20160204099
    Abstract: Performance of a semiconductor device is improved without increasing an area size of a semiconductor chip. For example, a source electrode of a power transistor and an upper electrode of a capacitor element have an overlapping portion. In other word, the upper electrode of the capacitor element is formed over the source electrode of the power transistor through a capacitor insulating film. That is, the power transistor and the capacitor element are arranged in a laminated manner in a thickness direction of the semiconductor chip. As a result, it becomes possible to add a capacitor element to be electrically coupled to the power transistor while suppressing an increase in planar size of the semiconductor chip.
    Type: Application
    Filed: November 4, 2015
    Publication date: July 14, 2016
    Inventors: Tohru KAWAI, Yasutaka NAKASHIBA, Yutaka AKIYAMA
  • Publication number: 20150115323
    Abstract: A semiconductor device including a first nitride semiconductor layer formed over a substrate, a second nitride semiconductor layer formed on the first nitride semiconductor layer and having a band gap wider than that of the first nitride semiconductor layer, a trench penetrating through the second nitride semiconductor layer to reach the middle of the first nitride semiconductor layer, a conductive film formed at a corner portion corresponding to an end portion of a bottom surface of the trench and a gate electrode disposed via a gate insulating film inside the trench including a region on the conductive film.
    Type: Application
    Filed: December 24, 2014
    Publication date: April 30, 2015
    Inventors: Tohru Kawai, Takashi Inoue, Tatsuo Nakayama, Yasuhiro Okamoto, Hironobu Miyamoto
  • Publication number: 20150060948
    Abstract: A field plate causes excessive gate capacitance that interferes with high-speed transistor switching. To suppress the excessive gate capacitance, an aperture includes a first side wall positioned on the side of a drain electrode, and a second side wall positioned on the side of a source electrode. A gate electrode at the same time includes a first side surface facing opposite the drain electrode as seen from a plan view. The first side surface of the gate electrode is positioned on the inner side of the first side wall and the second side wall as seen from a flat view. Moreover, a portion of a first field plate is embedded between the first side surface and the first side wall. The gate electrode and the first field plate are electrically insulated by a first insulation member.
    Type: Application
    Filed: August 29, 2014
    Publication date: March 5, 2015
    Inventors: Tohru KAWAI, Yutaka AKIYAMA, Yasutaka NAKASHIBA