Patents by Inventor Digh Hisamoto

Digh Hisamoto 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: 20210043753
    Abstract: A part of the semiconductor substrate is processed to form fins protruding from the upper surface of the semiconductor substrate. Next, an interlayer insulating film is formed on the semiconductor substrate including the fin FA, and an opening is formed in the interlayer insulating film. Next, a dummy pattern including the dummy material and the insulating film is formed in the opening in a self-aligned manner. Thereafter, the dummy pattern is replaced with a memory gate electrode, a control gate electrode, and the like.
    Type: Application
    Filed: October 26, 2020
    Publication date: February 11, 2021
    Inventors: Digh HISAMOTO, Yoshiyuki KAWASHIMA
  • Patent number: 10910394
    Abstract: A semiconductor memory array includes a first nonvolatile memory cell having a first charge storage layer and a first gate electrode and a second nonvolatile memory cell, adjacent to the first memory cell in a first direction, having a second charge storage layer and a second gate electrode. The first and second electrodes extend in a second direction perpendicular to the first direction, the first electrode has a first contact section extending toward the second electrode in the first direction, and the second electrode has a second contact section extending toward the first electrode in the first direction. The first and second contact positions are shifted in the second direction, respectively, and the first electrode and the first contact section are electrically separated from the second electrode and the second contact section.
    Type: Grant
    Filed: May 22, 2020
    Date of Patent: February 2, 2021
    Assignee: Renesas Electronics Corporation
    Inventors: Tsutomu Okazaki, Akira Kato, Kan Yasui, Kyoya Nitta, Digh Hisamoto, Yasushi Ishii, Daisuke Okada, Toshihiro Tanaka, Toshikazu Matsui
  • Patent number: 10854730
    Abstract: A part of the semiconductor substrate is processed to form fins protruding from the upper surface of the semiconductor substrate. Next, an interlayer insulating film is formed on the semiconductor substrate including the fin FA, and an opening is formed in the interlayer insulating film. Next, a dummy pattern including the dummy material and the insulating film is formed in the opening in a self-aligned manner. Thereafter, the dummy pattern is replaced with a memory gate electrode, a control gate electrode, and the like.
    Type: Grant
    Filed: June 20, 2019
    Date of Patent: December 1, 2020
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Digh Hisamoto, Yoshiyuki Kawashima
  • Publication number: 20200357807
    Abstract: A semiconductor memory array includes a first nonvolatile memory cell having a first charge storage layer and a first gate electrode and a second nonvolatile memory cell, adjacent to the first memory cell in a first direction, having a second charge storage layer and a second gate electrode. The first and second electrodes extend in a second direction perpendicular to the first direction, the first electrode has a first contact section extending toward the second electrode in the first direction, and the second electrode has a second contact section extending toward the first electrode in the first direction. The first and second contact positions are shifted in the second direction, respectively, and the first electrode and the first contact section are electrically separated from the second electrode and the second contact section.
    Type: Application
    Filed: May 22, 2020
    Publication date: November 12, 2020
    Inventors: Tsutomu OKAZAKI, Akira KATO, Kan YASUI, Kyoya NITTA, Digh HISAMOTO, Yasushi ISHII, Daisuke OKADA, Toshihiro TANAKA, Toshikazu MATSUI
  • Patent number: 10818679
    Abstract: In a MONOS memory of the split-gate type formed by a field effect transistor formed on a fin, it is prevented that the rewrite lifetime of the MONOS memory is reduced due to charges being locally transferred into and out of an ONO film in the vicinity of the top of the fin by repeating the write operation and the erase operation. By forming a source region at a position spaced downward from a first upper surface of the fin in a region directly below a memory gate electrode, the current is prevented from flowing concentratedly at the upper end of the fin.
    Type: Grant
    Filed: July 2, 2019
    Date of Patent: October 27, 2020
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Digh Hisamoto, Yoshiyuki Kawashima
  • Patent number: 10790386
    Abstract: A silicon carbide semiconductor device includes an n-type silicon carbide semiconductor substrate, a drain electrode electrically connected to a rear face, an n-type semiconductor layer having a second impurity concentration lower than the first impurity concentration, a p-type first semiconductor region, an n-type second semiconductor region, and an n-type third semiconductor region. A trench is formed having a gate electrode therein in which the bottom face of the trench contacts the p-type semiconductor region. A metal layer is electrically connected to the third semiconductor region, and a source electrode electrically connects the second semiconductor region and the metal layer to each other.
    Type: Grant
    Filed: December 11, 2018
    Date of Patent: September 29, 2020
    Assignee: HITACHI, LTD.
    Inventors: Yuan Bu, Hiroshi Miki, Naoki Tega, Naoki Watanabe, Digh Hisamoto, Takeru Suto
  • Patent number: 10692878
    Abstract: A semiconductor memory array includes a first nonvolatile memory cell having a first charge storage layer and a first gate electrode and a second nonvolatile memory cell, adjacent to the first memory cell in a first direction, having a second charge storage layer and a second gate electrode. The first and second electrodes extend in a second direction perpendicular to the first direction, the first electrode has a first contact section extending toward the second electrode in the first direction, and the second electrode has a second contact section extending toward the first electrode in the first direction. The first and second contact positions are shifted in the second direction, respectively, and the first electrode and the first contact section are electrically separated from the second electrode and the second contact section.
    Type: Grant
    Filed: August 27, 2019
    Date of Patent: June 23, 2020
    Assignee: Renesas Electronics Corporation
    Inventors: Tsutomu Okazaki, Akira Kato, Kan Yasui, Kyoya Nitta, Digh Hisamoto, Yasushi Ishii, Daisuke Okada, Toshihiro Tanaka, Toshikazu Matsui
  • Publication number: 20200035693
    Abstract: In a MONOS memory of the split-gate type formed by a field effect transistor formed on a fin, it is prevented that the rewrite lifetime of the MONOS memory is reduced due to charges being locally transferred into and out of an ONO film in the vicinity of the top of the fin by repeating the write operation and the erase operation. By forming a source region at a position spaced downward from a first upper surface of the fin in a region directly below a memory gate electrode, the current is prevented from flowing concentratedly at the upper end of the fin.
    Type: Application
    Filed: July 2, 2019
    Publication date: January 30, 2020
    Inventors: Digh HISAMOTO, Yoshiyuki KAWASHIMA
  • Publication number: 20200006526
    Abstract: A part of the semiconductor substrate is processed to form fins protruding from the upper surface of the semiconductor substrate. Next, an interlayer insulating film is formed on the semiconductor substrate including the fin FA, and an opening is formed in the interlayer insulating film. Next, a dummy pattern including the dummy material and the insulating film is formed in the opening in a self-aligned manner. Thereafter, the dummy pattern is replaced with a memory gate electrode, a control gate electrode, and the like.
    Type: Application
    Filed: June 20, 2019
    Publication date: January 2, 2020
    Inventors: Digh HISAMOTO, Yoshiyuki KAWASHIMA
  • Publication number: 20190386013
    Abstract: A semiconductor memory array includes a first nonvolatile memory cell having a first charge storage layer and a first gate electrode and a second nonvolatile memory cell, adjacent to the first memory cell in a first direction, having a second charge storage layer and a second gate electrode. The first and second electrodes extend in a second direction perpendicular to the first direction, the first electrode has a first contact section extending toward the second electrode in the first direction, and the second electrode has a second contact section extending toward the first electrode in the first direction. The first and second contact positions are shifted in the second direction, respectively, and the first electrode and the first contact section are electrically separated from the second electrode and the second contact section.
    Type: Application
    Filed: August 27, 2019
    Publication date: December 19, 2019
    Inventors: Tsutomu OKAZAKI, Akira KATO, Kan YASUI, Kyoya NITTA, Digh HISAMOTO, Yasushi ISHII, Daisuke OKADA, Toshihiro TANAKA, Toshikazu MATSUI
  • Publication number: 20190319103
    Abstract: The purpose of the present invention is to provide a semiconductor device comprising an epitaxial layer formed on a SiC substrate, and a CMOS formed in the top part of the epitaxial layer, wherein growth of any defects present at the interface between the SiC substrate and the epitaxial layer is suppressed, and the reliability of the semiconductor device is improved. As a means to achieve the foregoing, a semiconductor device is formed such that the distance from a p-type diffusion layer to the interface between an n-type epitaxial layer and an n-type semiconductor substrate is larger than the thickness of a depletion layer that extends from the p-type diffusion layer to the back side of the n-type semiconductor substrate in response to the potential difference between a substrate electrode and another substrate electrode.
    Type: Application
    Filed: October 24, 2017
    Publication date: October 17, 2019
    Inventors: Masahiro MASUNAGA, Shintaroh SATO, Akio SHIMA, Digh HISAMOTO
  • Patent number: 10396089
    Abstract: A semiconductor memory array includes a first nonvolatile memory cell having a first charge storage layer and a first gate electrode and a second nonvolatile memory cell, adjacent to the first memory cell in a first direction, having a second charge storage layer and a second gate electrode. The first and second electrodes extend in a second direction perpendicular to the first direction, the first electrode has a first contact section extending toward the second electrode in the first direction, and the second electrode has a second contact section extending toward the first electrode in the first direction. The first and second contact positions are shifted in the second direction, respectively, and the first electrode and the first contact section are electrically separated from the second electrode and the second contact section.
    Type: Grant
    Filed: November 27, 2018
    Date of Patent: August 27, 2019
    Assignee: Renesas Electronics Corporation
    Inventors: Tsutomu Okazaki, Daisuke Okada, Kyoya Nitta, Toshihiro Tanaka, Akira Kato, Toshikazu Matsui, Yasushi Ishii, Digh Hisamoto, Kan Yasui
  • Publication number: 20190229211
    Abstract: A silicon carbide semiconductor device includes an n-type silicon carbide semiconductor substrate, a drain electrode electrically connected to a rear face, an n-type semiconductor layer having a second impurity concentration lower than the first impurity concentration, a p-type first semiconductor region, an n-type second semiconductor region, an n-type third semiconductor region, a trench having a first side face and a second side face opposing to each other and a third side face intersecting with the first side face and the second side face, a gate electrode formed in the trench with a gate insulating film interposed therebetween, a metal layer electrically connected to the third semiconductor region, and a source electrode electrically connecting the second semiconductor region and the metal layer to each other.
    Type: Application
    Filed: December 11, 2018
    Publication date: July 25, 2019
    Applicant: HITACHI, LTD.
    Inventors: Yuan BU, Hiroshi MIKI, Naoki TEGA, Naoki WATANABE, Digh HISAMOTO, Takeru SUTO
  • Publication number: 20190096896
    Abstract: A semiconductor memory array includes a first nonvolatile memory cell having a first charge storage layer and a first gate electrode and a second nonvolatile memory cell, adjacent to the first memory cell in a first direction, having a second charge storage layer and a second gate electrode. The first and second electrodes extend in a second direction perpendicular to the first direction, the first electrode has a first contact section extending toward the second electrode in the first direction, and the second electrode has a second contact section extending toward the first electrode in the first direction. The first and second contact positions are shifted in the second direction, respectively, and the first electrode and the first contact section are electrically separated from the second electrode and the second contact section.
    Type: Application
    Filed: November 27, 2018
    Publication date: March 28, 2019
    Inventors: Tsutomu OKAZAKI, Daisuke OKADA, Kyoya NITTA, Toshihiro TANAKA, Akira KATO, Toshikazu MATSUI, Yasushi ISHII, Digh HISAMOTO, Kan YASUI
  • Patent number: 10147488
    Abstract: Provided is a semiconductor device including nonvolatile memory cells each including a FinFET having excellent memory characteristics. The semiconductor device includes a semiconductor substrate, memory cells each formed in the semiconductor substrate and having a split-gate structure including an opposed-gate selection gate electrode, a memory gate electrode, and a pair of terminals, and a word line driver circuit which supplies a selection voltage to a selection gate electrode of the selected one of the memory cells and supplies a non-selection voltage to the selection gate electrode of the non-selected one of the memory cells. The word line driver circuit supplies, as the non-selection voltage, a voltage which is negative or positive relative to a potential in the semiconductor substrate so as to bring a selection transistor corresponding to the selection gate electrode of the non-selected memory cell into an OFF state.
    Type: Grant
    Filed: July 2, 2017
    Date of Patent: December 4, 2018
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventor: Digh Hisamoto
  • Patent number: 10141324
    Abstract: A semiconductor memory array includes a first nonvolatile memory cell having a first charge storage layer and a first gate electrode and a second nonvolatile memory cell, adjacent to the first memory cell in a first direction, having a second charge storage layer and a second gate electrode. The first and second electrodes extend in a second direction perpendicular to the first direction, the first electrode has a first contact section extending toward the second electrode in the first direction, and the second electrode has a second contact section extending toward the first electrode in the first direction. The first and second contact positions are shifted in the second direction, respectively, and the first electrode and the first contact section are electrically separated from the second electrode and the second contact section.
    Type: Grant
    Filed: April 28, 2017
    Date of Patent: November 27, 2018
    Assignee: Renesas Electronics Corporation
    Inventors: Tsutomu Okazaki, Daisuke Okada, Kyoya Nitta, Toshihiro Tanaka, Akira Kato, Toshikazu Matsui, Yasushi Ishii, Digh Hisamoto, Kan Yasui
  • Patent number: 10062759
    Abstract: A MOSFET using a SiC substrate has a problem that a carbon-excess layer is formed on a surface by the application of mechanical stress due to thermal oxidation and the carbon-excess layer degrades mobility of channel carriers. In the invention, (1) a layer containing carbon-carbon bonds is removed; (2) a gate insulating film is formed by a deposition method; and (3) an interface between a crystal surface and the insulating film is subjected to an interface treatment at a low temperature for a short time. Due to this, the carbon-excess layer causing characteristic degradation is effectively eliminated, and at the same time, dangling bonds can be effectively eliminated by subjecting an oxide film and an oxynitride film to an interface treatment.
    Type: Grant
    Filed: March 29, 2013
    Date of Patent: August 28, 2018
    Assignee: HITACHI, LTD.
    Inventors: Digh Hisamoto, Keisuke Kobayashi, Naoki Tega, Toshiyuki Ohno, Hirotaka Hamamura, Mieko Matsumura
  • Patent number: 10032871
    Abstract: A MOSFET using a SiC substrate has a problem that a carbon-excess layer is formed on a surface by the application of mechanical stress due to thermal oxidation and the carbon-excess layer degrades mobility of channel carriers. In the invention, (1) a layer containing carbon-carbon bonds is removed; (2) a gate insulating film is formed by a deposition method; and (3) an interface between a crystal surface and the insulating film is subjected to an interface treatment at a low temperature for a short time. Due to this, the carbon-excess layer causing characteristic degradation is effectively eliminated, and at the same time, dangling bonds can be effectively eliminated by subjecting an oxide film and an oxynitride film to an interface treatment.
    Type: Grant
    Filed: March 29, 2013
    Date of Patent: July 24, 2018
    Assignee: HITACHI, LTD.
    Inventors: Digh Hisamoto, Keisuke Kobayashi, Naoki Tega, Toshiyuki Ohno, Hirotaka Hamamura, Mieko Matsumura
  • Publication number: 20180082745
    Abstract: Provided is a semiconductor device including nonvolatile memory cells each including a FinFET having excellent memory characteristics. The semiconductor device includes a semiconductor substrate, memory cells each formed in the semiconductor substrate and having a split-gate structure including an opposed-gate selection gate electrode, a memory gate electrode, and a pair of terminals, and a word line driver circuit which supplies a selection voltage to a selection gate electrode of the selected one of the memory cells and supplies a non-selection voltage to the selection gate electrode of the non-selected one of the memory cells. The word line driver circuit supplies, as the non-selection voltage, a voltage which is negative or positive relative to a potential in the semiconductor substrate so as to bring a selection transistor corresponding to the selection gate electrode of the non-selected memory cell into an OFF state.
    Type: Application
    Filed: July 2, 2017
    Publication date: March 22, 2018
    Inventor: Digh HISAMOTO
  • Publication number: 20180019748
    Abstract: A semiconductor device includes a driver circuit having a plurality of FinFETs, a memory cell having a plurality of FinFETs and supplied with a first output signal from the driver circuit through each of word lines, a first power supply wiring supplied with a first power supply potential, a second power supply wiring supplied with a second power supply potential, and a ground potential setting circuit which is coupled to the first power supply wiring, the second power supply wiring, and the driver circuit and which selects the first power supply potential or the second power supply potential and supplies the same to the driver circuit as an operating potential. An N-type FinFET of the FinFETs included in the driver circuit is supplied with the first power supply potential or the second power supply potential selected by the ground potential setting circuit.
    Type: Application
    Filed: May 16, 2017
    Publication date: January 18, 2018
    Inventor: Digh HISAMOTO