Patents by Inventor Jiro Yugami

Jiro Yugami 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: 20030054613
    Abstract: This semiconductor device manufacturing method comprises the steps of: forming a thick gate oxide film (thick oxide film) in a first region of a substrate, forming a thin gate oxide film (thin oxide layer) in a second region, and then, applying oxynitridation to these gate oxide films; forming gate electrodes to 1d on these gate oxide films; and implanting an ion that contains nitrogen or nitrogen atoms into at least one part of an interface between the hick gate oxide film (thick oxide film) and the substrate before or after the step of forming the gate electrodes, thereby forming a highly oxy-nitrided region. In this manner, in a semiconductor device in which there coexist a MISFET having a thin gate insulation film and a MISFET having a thick gate insulation film, hot carrier reliability of the MISFET having the thick gate insulation film is improved.
    Type: Application
    Filed: November 6, 2002
    Publication date: March 20, 2003
    Applicant: Hitachi, Ltd.
    Inventors: Eiichi Murakami, Akio Nishida, Kazunori Umeda, Kousuke Okuyama, Toshiaki Yamanaka, Jiro Yugami, Shinichiro Kimura
  • Patent number: 6521943
    Abstract: Disclosed is a semiconductor device (e.g., nonvolatile semiconductor memory device) and method of forming the device. The device includes a gate electrode (e.g., floating gate electrode) having a first layer of an amorphous silicon film, or a polycrystalline silicon thin film or a film of a combination of amorphous and polycrystalline silicon, on the gate insulating film. Where the film includes polycrystalline silicon, the thickness of the film is less than 10 nm. A thicker polycrystalline silicon film can be provided on or overlying the first layer. The memory device can increase the write/erase current significantly without increasing the low electric field leakage current after application of stresses, which in turn reduces write/erase time substantially.
    Type: Grant
    Filed: March 7, 2000
    Date of Patent: February 18, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Toshiyuki Mine, Jiro Yugami, Takashi Kobayashi, Masahiro Ushiyama
  • Publication number: 20030022444
    Abstract: Disclosed is a semiconductor device (e.g., nonvolatile semiconductor memory device) and method of forming the device. The device includes a gate electrode (e.g., floating gate electrode) having a first layer of an amorphous silicon film, or a polycrystalline silicon thin film or a film of a combination of amorphous and polycrystalline silicon, on the gate insulating film. Where the film includes polycrystalline silicon, the thickness of the film is less than 10 nm. A thicker polycrystalline silicon film can be provided on or overlying the first layer. The memory device can increase the write/erase current significantly without increasing the low electric field leakage current after application of stresses, which in turn reduces write/erase time substantially.
    Type: Application
    Filed: September 23, 2002
    Publication date: January 30, 2003
    Inventors: Toshiyuki Mine, Jiro Yugami, Takashi Kobayashi, Masahiro Ushiyama
  • Publication number: 20020072180
    Abstract: There is provided a semiconductor device configured as follows. On a semiconductor substrate, a titanium oxide film which is an insulating film having a higher dielectric constant than that of a silicon dioxide film is formed as a gate insulating film, and a gate electrode is disposed thereon, resulting in a field effect transistor. The end portions in the gate length direction of the titanium oxide film are positioned inwardly from the respective end portions on the source side and on the drain side of the gate electrode, and the end portions of the titanium oxide film are positioned in a region in which the gate electrode overlaps with the source region and the drain region in plan configuration. This semiconductor device operates at a high speed, and is excellent in short channel characteristics and driving current. Further, in the semiconductor device, the amount of metallic elements introduced into a silicon substrate is small.
    Type: Application
    Filed: December 7, 2001
    Publication date: June 13, 2002
    Inventors: Jiro Yugami, Natsuki Yokoyama, Toshiyuki Mine, Yasushi Goto
  • Publication number: 20020045360
    Abstract: This semiconductor device manufacturing method comprises the steps of: forming a thick gate oxide film (thick oxide film) in a first region of a substrate, forming a thin gate oxide film (thin oxide layer) in a second region, and then, applying oxynitridation to these gate oxide films; forming gate electrodes to 1d on these gate oxide films; and implanting an ion that contains nitrogen or nitrogen atoms into at least one part of an interface between the hick gate oxide film (thick oxide film) and the substrate before or after the step of forming the gate electrodes, thereby forming a highly oxy-nitrided region. In this manner, in a semiconductor device in which there coexist a MISFET having a thin gate insulation film and a MISFET having a thick gate insulation film, hot carrier reliability of the MISFET having the thick gate insulation film is improved.
    Type: Application
    Filed: August 31, 2001
    Publication date: April 18, 2002
    Inventors: Eiichi Murakami, Akio Nishida, Kazunori Umeda, Kousuke Okuyama, Toshiaki Yamanaka, Jiro Yugami, Shinichiro Kimura
  • Publication number: 20020000628
    Abstract: The present invention provides a MOS semiconductor device which enables gate leakage current reduction with a thinner gate dielectric film for higher speed, and a production method thereof. According to the present invention, a gate dielectric film 6 is made as follows: after forming a silicon nitride film 3 with a specified thickness, it is annealed in an oxidizing atmosphere to form silicon oxide 4 on the silicon nitride film 3, then this silicon oxide 4 is completely removed by exposure to a dissolving liquid. As a result, at depths between 0.12 nm and 0.5 nm from the top surface of the silicon nitride film 3 in the gate dielectric film 6 whose main constituent elements are silicon, nitrogen and oxygen, the nitrogen concentration is higher than the oxygen concentration. This enables the use of a thinner gate dielectric film with silicon, nitrogen and oxygen as main constituent elements while at the same time realizing reduction in leakage currents.
    Type: Application
    Filed: June 29, 2001
    Publication date: January 3, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Shimpei Tsujikawa, Jiro Yugami, Toshiyuki Mine, Masahiro Ushiyama
  • Patent number: 6144062
    Abstract: Disclosed is a semiconductor device (e.g., nonvolatile semiconductor memory device) and method of forming the device. The device includes a gate electrode (e.g., floating gate electrode) having a first layer of an amorphous silicon film, or a polycrystalline silicon thin film or a film of a combination of amorphous and polycrystalline silicon, on the gate insulating film. Where the film includes polycrystalline silicon, the thickness of the film is less than 10 nm. A thicker polycrystalline silicon film can be provided on or overlying the first layer. The memory device can increase the write/erase current significantly without increasing the low electric field leakage current after application of stresses, which in turn reduces write/erase time substantially.
    Type: Grant
    Filed: March 13, 1998
    Date of Patent: November 7, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Toshiyuki Mine, Jiro Yugami, Takashi Kobayashi, Masahiro Ushiyama
  • Patent number: 5091761
    Abstract: Disclosed is a semiconductor device including a charge storage capacitor having a storage electrode which is electrically connected to a switching transistor through a contact hole provided in an insulator and which has a greater film thickness than the radius of the contact hole, at least a part of the storage electrode being disposed above a data line. It is possible to reduce the memory cell area while preventing lowering in the capacitance, and thus realize high density and high integration of semiconductor devices.
    Type: Grant
    Filed: July 25, 1989
    Date of Patent: February 25, 1992
    Assignee: Hitachi, Ltd.
    Inventors: Atsushi Hiraiwa, Shinichiro Kimura, Toshiyuki Mine, Takashi Kobayashi, Tokuo Kure, Shinpei Iijima, Jiro Yugami
  • Patent number: 4989056
    Abstract: A capacitor having a first electrode, a thin insulator formed on said first electrode and a second electrode formed on said insulator wherein said first and second electrodes are composed of semiconductors that are of complementary conductivity type. Therefore, the current that flows through the capacitor insulator is efficiently suppressed while the thickness of the insulator is decreased, making it possible to realize a capacitor of a small area yet having a large capacitance.
    Type: Grant
    Filed: May 10, 1989
    Date of Patent: January 29, 1991
    Assignee: Hitachi, Ltd.
    Inventors: Atsushi Hiraiwa, Shinpei Iijima, Jiro Yugami