Patents by Inventor Moriya Iwai

Moriya Iwai 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: 7314797
    Abstract: A semiconductor device is capable of being applied with both a positive and a negative voltage to its control gate, and writing to its memory requires a low voltage. A control gate is formed on a memory unit region of a field oxide film, and an inter-layer silicon oxide film is formed on its surface. A gate oxide film for a non-volatile memory is formed on a P substrate between N type diffusion layers. The floating gate is formed on the inter-layer silicon oxide film, the field oxide film, and the gate oxide film for the non-volatile memory. Since a large coupling ratio between the control gate and the floating gate is available on the field oxide film, memory rewriting requires only a low voltage. Further, since the control gate is formed by a poly silicon film, both a positive voltage and a negative voltage can be applied to the control gate.
    Type: Grant
    Filed: August 18, 2005
    Date of Patent: January 1, 2008
    Assignee: Ricoh Company, Ltd.
    Inventors: Moriya Iwai, Masaaki Yoshida, Hiroaki Nakanishi
  • Publication number: 20050275041
    Abstract: A semiconductor device is capable of being applied with both a positive and a negative voltage to its control gate, and writing to its memory requires a low voltage. A control gate is formed on a memory unit region of a field oxide film, and an inter-layer silicon oxide film is formed on its surface. A gate oxide film for a non-volatile memory is formed on a P substrate between N type diffusion layers. The floating gate is formed on the inter-layer silicon oxide film, the field oxide film, and the gate oxide film for the non-volatile memory. Since a large coupling ratio between the control gate and the floating gate is available on the field oxide film, memory rewriting requires only a low voltage. Further, since the control gate is formed by a poly silicon film, both a positive voltage and a negative voltage can be applied to the control gate.
    Type: Application
    Filed: August 18, 2005
    Publication date: December 15, 2005
    Inventors: Moriya Iwai, Masaaki Yoshida, Hiroaki Nakanishi
  • Patent number: 6949790
    Abstract: A semiconductor device is capable of being applied with both a positive and a negative voltage to its control gate, and writing to its memory requires a low voltage. A control gate is formed on a memory unit region of a field oxide film, and an inter-layer silicon oxide film is formed on its surface. A gate oxide film for a non-volatile memory is formed on a P substrate between N type diffusion layers. The floating gate is formed on the inter-layer silicon oxide film, the field oxide film, and the gate oxide film for the non-volatile memory. Since a large coupling ratio between the control gate and the floating gate is available on the field oxide film, memory rewriting requires only a low voltage. Further, since the control gate is formed by a poly silicon film, both a positive voltage and a negative voltage can be applied to the control gate.
    Type: Grant
    Filed: September 18, 2002
    Date of Patent: September 27, 2005
    Assignee: Ricoh Company, Ltd.
    Inventors: Moriya Iwai, Masaaki Yoshida, Hiroaki Nakanishi
  • Publication number: 20040157394
    Abstract: A semiconductor device is capable of being applied with both a positive and a negative voltage to its control gate, and writing to its memory requires a low voltage. A control gate is formed on a memory unit region of a field oxide film, and an inter-layer silicon oxide film is formed on its surface. A gate oxide film for a non-volatile memory is formed on a P substrate between N type diffusion layers. The floating gate is formed on the inter-layer silicon oxide film, the field oxide film, and the gate oxide film for the non-volatile memory. Since a large coupling ratio between the control gate and the floating gate is available on the field oxide film, memory rewriting requires only a low voltage. Further, since the control gate is formed by a poly silicon film, both a positive voltage and a negative voltage can be applied to the control gate.
    Type: Application
    Filed: December 4, 2003
    Publication date: August 12, 2004
    Inventors: Moriya Iwai, Masaaki Yoshida, Hiroaki Nakanishi