Patents by Inventor Atsushi Yoshitomi

Atsushi Yoshitomi 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: 11742413
    Abstract: Reliability and performance of a semiconductor device are improved. First, a first mask pattern is formed on the semiconductor substrate in each of first to third regions. Next, a second mask pattern made of a material that is different from a material configuring the first mask pattern is formed on a side surface of the first mask pattern and on the semiconductor substrate in each of the first to third regions. Next, by an anisotropic etching process performed to the semiconductor substrate, a plurality of fins protruding from the recessed upper surface of the semiconductor substrate are formed. In the manner, fins each having a different structure from that of a fin in the first region can be formed in the second and third regions.
    Type: Grant
    Filed: March 3, 2021
    Date of Patent: August 29, 2023
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventor: Atsushi Yoshitomi
  • Publication number: 20210336039
    Abstract: Reliability and performance of a semiconductor device are improved. First, a first mask pattern is formed on the semiconductor substrate in each of first to third regions. Next, a second mask pattern made of a material that is different from a material configuring the first mask pattern is formed on a side surface of the first mask pattern and on the semiconductor substrate in each of the first to third regions. Next, by an anisotropic etching process performed to the semiconductor substrate, a plurality of fins protruding from the recessed upper surface of the semiconductor substrate are formed. In the manner, fins each having a different structure from that of a fin in the first region can be formed in the second and third regions.
    Type: Application
    Filed: March 3, 2021
    Publication date: October 28, 2021
    Inventor: Atsushi YOSHITOMI
  • Patent number: 10483276
    Abstract: To provide a semiconductor device capable of having an ONO-film-configuring second oxide film with an optimized thickness. The semiconductor device has a semiconductor substrate having a first surface, a first gate insulating film placed on the first surface located in a first transistor formation region, and a second gate insulating film placed on the first surface located in a second transistor formation region. The first gate insulating film has a first oxide film, a first nitride film placed thereon, and a second oxide film placed thereon. The second oxide film includes a first layer and a second layer placed thereon. The height of the first surface in a region where the second insulating film is placed is lower than that in a region where the first gate insulating film is placed. The nitrogen concentration in the first layer is higher than that in the second layer.
    Type: Grant
    Filed: June 27, 2018
    Date of Patent: November 19, 2019
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Yoshiyuki Kawashima, Atsushi Yoshitomi
  • Patent number: 10439032
    Abstract: To provide a semiconductor device having improved reliability by relaxing the unevenness of the injection distribution of electrons and holes into a charge accumulation film attributable to the shape of the fin of a MONOS memory comprised of a fin transistor. Of a memory gate electrode configuring a memory cell formed above a fin, a portion contiguous to an ONO film that covers the upper surface of the fin and a portion contiguous to the ONO film that covers the side surface of the fin are made of electrode materials different in work function, respectively, and the boundary surface between them is located below the upper surface of the fin.
    Type: Grant
    Filed: May 14, 2018
    Date of Patent: October 8, 2019
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Atsushi Yoshitomi, Yoshiyuki Kawashima
  • Patent number: 10312254
    Abstract: The reliability and performances of a semiconductor device having a nonvolatile memory are improved. A control gate electrode is formed over a semiconductor substrate via a first insulation film. A memory gate electrode is formed over the semiconductor substrate via a second insulation film having a charge accumulation part. The second insulation film is formed across between the semiconductor substrate and the memory gate electrode, and between the control gate electrode and the memory gate electrode. Between the control gate electrode and the memory gate electrode, a third insulation film is formed between the second insulation film and the memory gate electrode. The third insulation film is not formed under the memory gate electrode. A part of the memory gate electrode is present under the lower end face of the third insulation film.
    Type: Grant
    Filed: September 8, 2017
    Date of Patent: June 4, 2019
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Atsushi Yoshitomi, Yoshiyuki Kawashima
  • Patent number: 10217872
    Abstract: A memory cell includes a control gate electrode and a memory gate electrode. The control gate electrode is formed over the upper surface and the sidewall of a fin FA including apart of a semiconductor substrate. The memory gate electrode is formed over one side surface of the control gate electrode and the upper surface and the sidewall of the fin through an ONO film, in a position adjacent to the one side surface of the control gate electrode. Further, the control gate electrode and the memory gate electrode are formed of n-type polycrystalline silicon. A first metal film is provided between the gate electrode and the control gate electrode. A second metal film is provided between the ONO film and the memory gate electrode. A work function of the first metal film is greater than a work function of the second metal film.
    Type: Grant
    Filed: June 17, 2017
    Date of Patent: February 26, 2019
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Yoshiyuki Kawashima, Masao Inoue, Atsushi Yoshitomi
  • Publication number: 20190035800
    Abstract: To provide a semiconductor device capable of having an ONO-film-configuring second oxide film with an optimized thickness. The semiconductor device has a semiconductor substrate having a first surface, a first gate insulating film placed on the first surface located in a first transistor formation region, and a second gate insulating film placed on the first surface located in a second transistor formation region. The first gate insulating film has a first oxide film, a first nitride film placed thereon, and a second oxide film placed thereon. The second oxide film includes a first layer and a second layer placed thereon. The height of the first surface in a region where the second insulating film is placed is lower than that in a region where the first gate insulating film is placed. The nitrogen concentration in the first layer is higher than that in the second layer.
    Type: Application
    Filed: June 27, 2018
    Publication date: January 31, 2019
    Inventors: Yoshiyuki KAWASHIMA, Atsushi YOSHITOMI
  • Publication number: 20180374924
    Abstract: To provide a semiconductor device having improved reliability by relaxing the unevenness of the injection distribution of electrons and holes into a charge accumulation film attributable to the shape of the fin of a MONOS memory comprised of a fin transistor. Of a memory gate electrode configuring a memory cell formed above a fin, a portion contiguous to an ONO film that covers the upper surface of the fin and a portion contiguous to the ONO film that covers the side surface of the fin are made of electrode materials different in work function, respectively, and the boundary surface between them is located below the upper surface of the fin.
    Type: Application
    Filed: May 14, 2018
    Publication date: December 27, 2018
    Applicant: Renesas Electronics Corporation
    Inventors: Atsushi YOSHITOMI, Yoshiyuki KAWASHIMA
  • Publication number: 20180076206
    Abstract: The reliability and performances of a semiconductor device having a nonvolatile memory are improved. A control gate electrode is formed over a semiconductor substrate via a first insulation film. A memory gate electrode is formed over the semiconductor substrate via a second insulation film having a charge accumulation part. The second insulation film is formed across between the semiconductor substrate and the memory gate electrode, and between the control gate electrode and the memory gate electrode. Between the control gate electrode and the memory gate electrode, a third insulation film is formed between the second insulation film and the memory gate electrode. The third insulation film is not formed under the memory gate electrode. A part of the memory gate electrode is present under the lower end face of the third insulation film.
    Type: Application
    Filed: September 8, 2017
    Publication date: March 15, 2018
    Inventors: Atsushi YOSHITOMI, Yoshiyuki KAWASHIMA
  • Publication number: 20180061997
    Abstract: A memory cell includes a control gate electrode and a memory gate electrode. The control gate electrode is formed over the upper surface and the sidewall of a fin FA including apart of a semiconductor substrate. The memory gate electrode is formed over one side surface of the control gate electrode and the upper surface and the sidewall of the fin through an ONO film, in a position adjacent to the one side surface of the control gate electrode. Further, the control gate electrode and the memory gate electrode are formed of n-type polycrystalline silicon. A first metal film is provided between the gate electrode and the control gate electrode. A second metal film is provided between the ONO film and the memory gate electrode. A work function of the first metal film is greater than a work function of the second metal film.
    Type: Application
    Filed: June 17, 2017
    Publication date: March 1, 2018
    Inventors: Yoshiyuki KAWASHIMA, Masao INOUE, Atsushi YOSHITOMI
  • Patent number: 9514946
    Abstract: An improvement is achieved in the performance of a semiconductor device including a memory element. Over a semiconductor substrate, a gate electrode for the memory element is formed via an insulating film as a gate insulating film for the memory element. The insulating film includes first, second, third, fourth, and fifth insulating films in order of being apart from the substrate. The second insulating film has a charge storing function. The band gap of each of the first and third insulating films is larger than a band gap of the second insulating film. The band gap of the fourth insulating film is smaller than the band gap of the third insulating film. The band gap of the fifth insulating film is smaller than the band gap of the fourth insulating film.
    Type: Grant
    Filed: May 14, 2015
    Date of Patent: December 6, 2016
    Assignee: Renesas Electronics Corporation
    Inventors: Masao Inoue, Yoshiki Maruyama, Tomoya Saito, Atsushi Yoshitomi
  • Publication number: 20150349143
    Abstract: An improvement is achieved in the performance of a semiconductor device including a memory element. Over a semiconductor substrate, a gate electrode for the memory element is formed via an insulating film as a gate insulating film for the memory element. The insulating film includes first, second, third, fourth, and fifth insulating films in order of being apart from the substrate. The second insulating film has a charge storing function. The band gap of each of the first and third insulating films is larger than a band gap of the second insulating film. The band gap of the fourth insulating film is smaller than the band gap of the third insulating film. The band gap of the fifth insulating film is smaller than the band gap of the fourth insulating film.
    Type: Application
    Filed: May 14, 2015
    Publication date: December 3, 2015
    Inventors: Masao Inoue, Yoshiki Maruyama, Tomoya Saito, Atsushi Yoshitomi