Patents by Inventor Satoru Sagou

Satoru Sagou 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).

  • Charged-particle-beam exposure device and charged-particle-beam exposure method
    Patent number: 6222195
    Abstract: A method of detecting deficiency of an aperture used in a charged-particle-beam exposure process employing at least two exposure columns is disclosed, where each of the two exposure columns passes a charged-particle beam through the aperture formed through a mask to shape a cross section of the charged-particle beam before exposing the charged-particle beam onto an object. The method includes the steps of mounting masks having the same aperture to the at least two exposure columns; scanning, in each of the at least two exposure columns, the charged-particle beam over an area containing a mark on a surface substantially at the same height as the object after passing the charged-particle beam through the same aperture; obtaining, in each of the at least two exposure columns, a signal waveform corresponding to the scan by detecting charged particles scattered by the mark; and comparing the signal waveform between the at least two exposure columns.
    Type: Grant
    Filed: August 11, 2000
    Date of Patent: April 24, 2001
    Assignee: Fujitsu Limited
    Inventors: Akio Yamada, Satoru Sagou, Hitoshi Watanabe, Satoru Yamazaki, Kiichi Sakamoto, Manabu Ohno, Kenichi Kawakami, Katsuhiko Kobayashi
  • Charged particle-beam exposure device and charged-particle-beam exposure method
    Patent number: 6137111
    Abstract: A method of detecting deficiency of an aperture used in a charged-particle-beam exposure process employing at least two exposure columns is disclosed, where each of the two exposure columns passes a charged-particle beam through the aperture formed through a mask to shape a cross section of the charged-particle beam before exposing the charged-particle beam onto an object. The method includes the steps of mounting masks having the same aperture to the at least two exposure columns; scanning, in each of the at least two exposure columns, the charged-particle beam over an area containing a mark on a surface substantially at the same height as the object after passing the charged-particle beam through the same aperture; obtaining, in each of the at least two exposure columns, a signal waveform corresponding to the scan by detecting charged particles scattered by the mark; and comparing the signal waveform between the at least two exposure columns.
    Type: Grant
    Filed: May 28, 1998
    Date of Patent: October 24, 2000
    Assignee: Fujitsu Limited
    Inventors: Akio Yamada, Satoru Sagou, Hitoshi Watanabe, Satoru Yamazaki, Kiichi Sakamoto, Manabu Ohno, Kenichi Kawakami, Katsuhiko Kobayashi
  • Method of detecting a deficiency in a charged-particle-beam exposure mask
    Patent number: 5830612
    Abstract: A method of detecting deficiency of an aperture used in a charged-particle-beam exposure process employing at least two exposure columns is disclosed, where each of the two exposure columns passes a charged-particle beam through the aperture formed through a mask to shape a cross section of the charged-particle beam before exposing the charged-particle beam onto an object. The method includes the steps of mounting masks having the same aperture to the at least two exposure columns; scanning, in each of the at least two exposure columns, the charged-particle beam over an area containing a mark on a surface substantially at the same height as the object after passing the charged-particle beam through the same aperture; obtaining, in each of the at least two exposure columns, a signal waveform corresponding to the scan by detecting charged particles scattered by the mark; and comparing the signal waveform between the at least two exposure columns.
    Type: Grant
    Filed: September 11, 1996
    Date of Patent: November 3, 1998
    Assignee: Fujitsu Limited
    Inventors: Akio Yamada, Satoru Sagou, Hitoshi Watanabe, Satoru Yamazaki, Kiichi Sakamoto, Manabu Ohno, Kenichi Kawakami, Katsuhiko Kobayashi