Patents by Inventor Tatsuo Yoneda

Tatsuo Yoneda 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: 7576392
    Abstract: A semiconductor device disclosed herein comprises a semiconductor layer which includes a first semiconductor region of a first conductivity type, a base region of a second conductivity type, and a plurality of second semiconductor regions of the first conductivity type; a gate wiring which is formed on the semiconductor layer via a first insulating film; a plurality of main electrodes which are electrically connected to the plurality of second semiconductor regions and which are insulated from the gate wiring, wherein the gate wiring is arranged between the main electrodes and upper surfaces of the main electrodes are higher than an upper surface of the uppermost layer of the gate wiring; and a connecting plate which is directly connected onto uppermost layers of the main electrodes.
    Type: Grant
    Filed: July 7, 2003
    Date of Patent: August 18, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takahiro Kawano, Kenichi Ogata, Tatsuo Yoneda
  • Patent number: 6919249
    Abstract: A semiconductor device comprises a semiconductor layer of a first conductivity type (2), a base region (3) formed proximal to the semiconductor layer, a source region (4) selectively placed over the base region, trenches (T), a gate insulating layer (7) and a gate electrode (6) provided on an inner wall of each of the trenches, and a source electrode (9) connected to the source region. The source region is higher in impurity concentration in a contact (4a) with the source electrode than in a contact with the gate insulating layer, and it is also higher in impurity concentration in the contact (4a) with the source electrode than in a contact with the base region.
    Type: Grant
    Filed: February 17, 2004
    Date of Patent: July 19, 2005
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takahiro Kawano, Tatsuo Yoneda, Hirobumi Matsuki
  • Publication number: 20040159885
    Abstract: A semiconductor device comprises a semiconductor layer of a first conductivity type (2), a base region (3) formed proximal to the semiconductor layer, a source region (4) selectively placed over the base region, trenches (T), a gate insulating layer (7) and a gate electrode (6) provided on an inner wall of each of the trenches, and a source electrode (9) connected to the source region. The source region is higher in impurity concentration in a contact (4a) with the source electrode than in a contact with the gate insulating layer, and it is also higher in impurity concentration in the contact (4a) with the source electrode than in a contact with the base region.
    Type: Application
    Filed: February 17, 2004
    Publication date: August 19, 2004
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Takahiro Kawano, Tatsuo Yoneda, Hirobumi Matsuki
  • Patent number: 6750511
    Abstract: A semiconductor device comprises a semiconductor layer of a first conductivity type (2), a base region (3) formed proximal to the semiconductor layer, a source region (4) selectively placed over the base region, trenches (T), a gate insulating layer (7) and a gate electrode (6) provided on an inner wall of each of the trenches, and a source electrode (9) connected to the source region. The source region is higher in impurity concentration in a contact (4a) with the source electrode than in a contact with the gate insulating layer, and it is also higher in impurity concentration in the contact (4a) with the source electrode than in a contact with the base region.
    Type: Grant
    Filed: September 19, 2002
    Date of Patent: June 15, 2004
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takahiro Kawano, Tatsuo Yoneda, Hirobumi Matsuki
  • Patent number: 6690061
    Abstract: The semiconductor device according to an aspect of the present invention includes: a semiconductor substrate of a first conductive type; a first semiconductor layer of the first conductive type formed on the main surface of the semiconductor substrate, the impurity concentration of the first semiconductor layer being lower than that of the semiconductor substrate; a second and third semiconductor layers of a second conductive type formed on the first semiconductor layer, the second and third semiconductor layers being isolated from each other; a first and second MOS transistors MOS1 and MOS2 of the first conductive type formed in the second and third semiconductor layers, the first semiconductor layer and the semiconductor substrate serving as drains of the first and second MOS transistors; and a conductive layer.
    Type: Grant
    Filed: September 25, 2002
    Date of Patent: February 10, 2004
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tatsuo Yoneda, Bungo Tanaka
  • Publication number: 20040016979
    Abstract: A semiconductor device disclosed herein comprises a semiconductor layer which includes a first semiconductor region of a first conductivity type, a base region of a second conductivity type, and a plurality of second semiconductor regions of the first conductivity type; a gate wiring which is formed on the semiconductor layer via a first insulating film; a plurality of main electrodes which are electrically connected to the plurality of second semiconductor regions and which are insulated from the gate wiring, wherein the gate wiring is arranged between the main electrodes and upper surfaces of the main electrodes are higher than an upper surface of the uppermost layer of the gate wiring; and a connecting plate which is directly connected onto uppermost layers of the main electrodes.
    Type: Application
    Filed: July 7, 2003
    Publication date: January 29, 2004
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Takahiro Kawano, Kenichi Ogata, Tatsuo Yoneda
  • Publication number: 20030075759
    Abstract: A semiconductor device comprises a semiconductor layer of a first conductivity type (2), a base region (3) formed proximal to the semiconductor layer, a source region (4) selectively placed over the base region, trenches (T), a gate insulating layer (7) and a gate electrode (6) provided on an inner wall of each of the trenches, and a source electrode (9) connected to the source region. The source region is higher in impurity concentration in a contact (4a) with the source electrode than in a contact with the gate insulating layer, and it is also higher in impurity concentration in the contact (4a) with the source electrode than in a contact with the base region.
    Type: Application
    Filed: September 19, 2002
    Publication date: April 24, 2003
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Takahiro Kawano, Tatsuo Yoneda, Hirobumi Matsuki
  • Publication number: 20030057503
    Abstract: The semiconductor device according to an aspect of the present invention includes: a semiconductor substrate of a first conductive type; a first semiconductor layer of the first conductive type formed on the main surface of the semiconductor substrate, the impurity concentration of the first semiconductor layer being lower than that of the semiconductor substrate; a second and third semiconductor layers of a second conductive type formed on the first semiconductor layer, the second and third semiconductor layers being isolated from each other; a first and second MOS transistors MOS1 and MOS2 of the first conductive type formed in the second and third semiconductor layers, the first semiconductor layer and the semiconductor substrate serving as drains of the first and second MOS transistors; and a conductive layer.
    Type: Application
    Filed: September 25, 2002
    Publication date: March 27, 2003
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tatsuo Yoneda, Bungo Tanaka
  • Patent number: 6521954
    Abstract: A semiconductor device includes a first semiconductor layer of a first conductivity type and a second semiconductor layer of a second conductivity type juxtaposed on a semiconductor substrate of the first conductivity type. The first semiconductor layer has an impurity concentration lower than that of the semiconductor substrate. The second semiconductor layer has at a central location a trench, which extends from the upper end toward the semiconductor substrate. A first region of the second conductivity type is formed to include an upper portion of the second semiconductor layer. A second region of the first conductivity type is formed in a surface of the first region. A gate electrode is disposed, through an insulating film, on a channel region, which is a surface portion of the first region between the second region and an upper portion of the first semiconductor layer.
    Type: Grant
    Filed: December 21, 2001
    Date of Patent: February 18, 2003
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shigeo Kouzuki, Yasunori Usui, Tatsuo Yoneda
  • Patent number: 6507088
    Abstract: A power semiconductor device of the present invention comprises a voltage drive type power MOS transistor, a series connection of a first resistor and Zener diode, a second resistor, and a series connection of a third resistor and MOS transistor. The power MOS transistor has a gate, source and drain. A drain-to-source voltage of the power MOS transistor is applied across the series connection of the first resistor and Zener diode. A gate-to-source voltage of the power MOS transistor is applied across the second resistor. The gate-to-source voltage of the power MOS transistor is applied across a series connection of a third resistor and the MOS transistor. The MOS transistor has a gate, source and drain. The gate of the MOS transistor is connected to a node between the first resistor and the Zener diode.
    Type: Grant
    Filed: March 20, 2001
    Date of Patent: January 14, 2003
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Tatsuo Yoneda
  • Publication number: 20020117711
    Abstract: The present invention provides a trench gate MOS transistor capable of reducing the threshold voltage required for a low voltage drive and, at the same time, capable of preventing the withstand voltage VSUS from being lowered. In the trench gate MOS transistor of the present invention, a thick trench side wall oxide film is formed after the trench etching step, followed by removing the trench side wall oxide film and subsequently forming a gate insulating film. In forming the trench side wall oxide film, the corner portions at the bottom and opening portion of the trench, which have a rectangular cross sectional shape, are rounded to improve the breakdown voltage of the gate insulating film.
    Type: Application
    Filed: February 4, 2000
    Publication date: August 29, 2002
    Inventor: Tatsuo Yoneda
  • Publication number: 20010023967
    Abstract: A power semiconductor device of the present invention comprises a voltage drive type power MOS transistor, a series connection of a first resistor and Zener diode, a second resistor, and a series connection of a third resistor and MOS transistor. The power MOS transistor has a gate, source and drain. A drain-to-source voltage of the power MOS transistor is applied across the series connection of the first resistor and Zener diode. A gate-to-source voltage of the power MOS transistor is applied across the second resistor. The gate-to-source voltage of the power MOS transistor is applied across a series connection of a third resistor and the MOS transistor. The MOS transistor has a gate, source and drain. The gate of the MOS transistor is connected to a node between the first resistor and the Zener diode.
    Type: Application
    Filed: March 20, 2001
    Publication date: September 27, 2001
    Inventor: Tatsuo Yoneda
  • Patent number: 5420450
    Abstract: A semiconductor device having stable breakdown voltage in wiring area. The semiconductor has a first conducting type semiconductor substrate with a plurality of second conducting type first semiconductor regions formed on one part of the surface of the first conducting type semiconductor substrate. A first conducting type high density diffused second semiconductor region is formed on one part of the surface within the second conducting type first semiconductor region. A gate electrode material extends across one part of the surface of the first conducting type semiconductor substrate, where one part of the surface of the first conducting type high density diffused second semiconductor region and the second conducting type first semiconductor region are not formed. An insulating film covers the gate electrode material and a metal source wiring is connected to the first conducting type high density diffused second semiconductor region and the second conducting type first semiconductor region.
    Type: Grant
    Filed: October 11, 1994
    Date of Patent: May 30, 1995
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tatsuo Yoneda, Kazuaki Suzuki
  • Patent number: D717747
    Type: Grant
    Filed: January 23, 2014
    Date of Patent: November 18, 2014
    Assignee: Sumitomo Electric Networks, Inc.
    Inventors: Hiroaki Nishimoto, Takahiro Kusumoto, Kenta Tsutiya, Mitsuhiro Matsuo, Hiroyuki Kohama, Tatsuo Yoneda
  • Patent number: D717748
    Type: Grant
    Filed: January 23, 2014
    Date of Patent: November 18, 2014
    Assignee: Sumitomo Electric Networks, Inc.
    Inventors: Hiroaki Nishimoto, Takahiro Kusumoto, Kenta Tsutiya, Mitsuhiro Matsuo, Hiroyuki Kohama, Tatsuo Yoneda
  • Patent number: RE47292
    Abstract: The semiconductor device according to an aspect of the present invention includes: a semiconductor substrate of a first conductive type; a first semiconductor layer of the first conductive type formed on the main surface of the semiconductor substrate, the impurity concentration of the first semiconductor layer being lower than that of the semiconductor substrate; a second and third semiconductor layers of a second conductive type formed on the first semiconductor layer, the second and third semiconductor layers being isolated from each other; a first and second MOS transistors MOS1 and MOS2 of the first conductive type formed in the second and third semiconductor layers, the first semiconductor layer and the semiconductor substrate serving as drains of the first and second MOS transistors; and a conductive layer.
    Type: Grant
    Filed: June 17, 2016
    Date of Patent: March 12, 2019
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tatsuo Yoneda, Bungo Tanaka