Patents by Inventor Yoshinori Obata

Yoshinori Obata 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: 7982466
    Abstract: A method for inspecting a semiconductor memory having nonvolatile memory cells using ferroelectric capacitors is disclosed which comprises, after shelf-aging the ferroelectric capacitor in a first polarized state, the steps of: (a) writing a second polarized state opposite to the first polarized state; (b) shelf-aging the ferroelectric capacitor in the second polarized state; and (c) reading the second polarized state. The temperature or voltage in the step (a) is lower than the temperature or voltage in the step (c). This method for inspecting a semiconductor memory enables to evaluate the imprint characteristics in a short time.
    Type: Grant
    Filed: November 6, 2006
    Date of Patent: July 19, 2011
    Assignee: Fujitsu Semiconductor Limited
    Inventors: Yukinobu Hikosaka, Tomohiro Takamatsu, Yoshinori Obata
  • Publication number: 20070058416
    Abstract: A method for inspecting a semiconductor memory having nonvolatile memory cells using ferroelectric capacitors is disclosed which comprises, after shelf-aging the ferroelectric capacitor in a first polarized state, the steps of: (a) writing a second polarized state opposite to the first polarized state; (b) shelf-aging the ferroelectric capacitor in the second polarized state; and (c) reading the second polarized state. The temperature or voltage in the step (a) is lower than the temperature or voltage in the step (c). This method for inspecting a semiconductor memory enables to evaluate the imprint characteristics in a short time.
    Type: Application
    Filed: November 6, 2006
    Publication date: March 15, 2007
    Applicant: FUJITSU LIMITED
    Inventors: Yukinobu Hikosaka, Tomohiro Takamatsu, Yoshinori Obata
  • Patent number: 6913970
    Abstract: A semiconductor device formed by forming contact holes in the insulating film, that covers the source/drain of the MOSFET and the capacitor in the memory cell region, on the lower electrode of the capacitor by the same steps, then filling the plugs into contact holes, and then forming the contact hole on the upper electrode of the capacitor. Accordingly, there can be provided the semiconductor device having the ferroelectric capacitor, capable of simplifying respective wiring connection structures to the upper electrode and the lower electrode of the capacitor by suppressing the damage to the capacitor formed over the transistor.
    Type: Grant
    Filed: November 26, 2002
    Date of Patent: July 5, 2005
    Assignee: Fujitsu Limited
    Inventors: Kenichi Inoue, Yoshinori Obata, Takeyasu Saito, Kaoru Saigoh, Naoya Sashida, Koji Tani, Jirou Miura, Tatsuya Yokota, Satoru Mihara, Yukinobu Hikosaka, Yasutaka Ozaki
  • Publication number: 20030080364
    Abstract: There are provided the steps of forming contact holes in the insulating film, that covers the source/drain of the MOSFET and the capacitor in the memory cell region, on the lower electrode of the capacitor by the same steps, then filling the plugs into the contact holes, and then forming the contact hole on the upper electrode of the capacitor. Accordingly, there can be provided the semiconductor device having the ferroelectric capacitor, capable of simplifying respective wiring connection structures to the upper electrode and the lower electrode of the capacitor by suppressing the damage to the capacitor formed over the transistor.
    Type: Application
    Filed: November 26, 2002
    Publication date: May 1, 2003
    Applicant: Fujitsu Limited
    Inventors: Kenichi Inoue, Yoshinori Obata, Takeyasu Saito, Kaoru Saigoh, Naoya Sashida, Koji Tani, Jirou Miura, Tatsuya Yokota, Satoru Mihara, Yukinobu Hikosaka, Yasutaka Ozaki
  • Patent number: 6509593
    Abstract: A semiconductor device formed by forming contact holes in the insulating film, that covers the source/drain of the MOSFET and the capacitor in the memory cell region, on the lower electrode of the capacitor by the same steps, then filling the plugs into the contact holes, and then forming the contact hole on the upper electrode of the capacitor. Accordingly, there can be provided the semiconductor device having the ferroelectric capacitor, capable of simplifying respective wiring connection structures to the upper electrode and the lower electrode of the capacitor by suppressing the damage to the capacitor formed over the transistor.
    Type: Grant
    Filed: December 29, 2000
    Date of Patent: January 21, 2003
    Assignee: Fujitsu Limited
    Inventors: Kenichi Inoue, Yoshinori Obata, Takeyasu Saito, Kaoru Saigoh, Naoya Sashida, Koji Tani, Jirou Miura, Tatsuya Yokota, Satoru Mihara, Yukinobu Hikosaka, Yasutaka Ozaki
  • Publication number: 20020011616
    Abstract: There are provided the steps of forming contact holes in the insulating film, that covers the source/drain of the MOSFET and the capacitor in the memory cell region, on the lower electrode of the capacitor by the same steps, then filling the plugs into the contact holes, and then forming the contact hole on the upper electrode of the capacitor. Accordingly, there can be provided the semiconductor device having the ferroelectric capacitor, capable of simplifying respective wiring connection structures to the upper electrode and the lower electrode of the capacitor by suppressing the damage to the capacitor formed over the transistor.
    Type: Application
    Filed: December 29, 2000
    Publication date: January 31, 2002
    Applicant: Fujitsu Limited
    Inventors: Kenichi Inoue, Yoshinori Obata, Takeyasu Saito, Kaoru Saigoh, Naoya Sashida, Koji Tani, Jirou Miura, Tatsuya Yokota, Satoru Mihara, Yukinobu Hikosaka, Yasutaka Ozaki
  • Patent number: 4871596
    Abstract: Artificial marble is produced by laminating a plurality of prepreg sheets formed by impregnating a porous substrate with a melamine resin composition which is composed of melamine resin and a modifier. The melamine resin is an unmodified melamine resin or an alcohol-etherified melamine resin in which formaldehyde-to-melamine molar ratio is between 1.2 to 3.0. The modifier is selected from alcohol, glycol, acrylic monomer, acrylic oligomer and vinyl acetate monomer. The artificial marble has a good stability in dimensions and it is suitable to apply the artificial marble to a composite panel or a decorative laminate panel which is free from tearing even after long time use.
    Type: Grant
    Filed: December 8, 1987
    Date of Patent: October 3, 1989
    Assignee: Aica Kogyo Co., Ltd.
    Inventors: Takashi Kamiya, Masaya Suzuki, Yoshinori Obata, Masaaki Watanabe, Isao Matsuoka