Patents by Inventor Michihiro Sakai

Michihiro Sakai 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: 8872139
    Abstract: A settling time acquisition method includes writing at least one reference pattern formed by at least one shot of a charged particle beam, writing an evaluation pattern, which has been formed by combination of the first and second shots of a charged particle beam shaped to first and second patterns of different sizes and whose width size is the same as that of the reference pattern, while changing, concerning beam shaping of the second shot, a settling time of a DAC amplifier, wherein writing is performed for each settling time, measuring the width size of the reference pattern, measuring the width size of the evaluation pattern for each settling time, calculating, for each settling time, a difference between the width sizes of the reference and evaluation patterns, and acquiring a settling time from each settling time of the DAC amplifier when the difference is not exceeding a threshold value.
    Type: Grant
    Filed: March 14, 2014
    Date of Patent: October 28, 2014
    Assignee: NuFlare Technology, Inc.
    Inventors: Rieko Nishimura, Michihiro Sakai
  • Publication number: 20140284500
    Abstract: A settling time acquisition method includes writing at least one reference pattern formed by at least one shot of a charged particle beam, writing an evaluation pattern, which has been formed by combination of the first and second shots of a charged particle beam shaped to first and second patterns of different sizes and whose width size is the same as that of the reference pattern, while changing, concerning beam shaping of the second shot, a settling time of a DAC amplifier, wherein writing is performed for each settling time, measuring the width size of the reference pattern, measuring the width size of the evaluation pattern for each settling time, calculating, for each settling time, a difference between the width sizes of the reference and evaluation patterns, and acquiring a settling time from each settling time of the DAC amplifier when the difference is not exceeding a threshold value.
    Type: Application
    Filed: March 14, 2014
    Publication date: September 25, 2014
    Applicant: NuFlure Technology, Inc.
    Inventors: Rieko NISHIMURA, Michihiro SAKAI
  • Patent number: 8076649
    Abstract: A charged particle beam writing apparatus includes a stage on which a target object is placed; an emitting unit configured to emit a charged particle beam to the stage side; a blocking unit arranged between the emitting unit and the stage and configured to block the charged particle beam emitted; a deflector having electrodes through which a current flows by applying a voltage and configured to deflect the charged particle beam passing between the electrodes onto the blocking unit by applying a predetermined voltage across the electrodes; an optical axis adjusting unit configured to correct optical axis deviation of the charged particle beam generated by continuously repeating irradiation (beam-ON) of the charged particle beam on a target object and blocking (beam-OFF) of the beam by applying a two-step voltage to the deflector; and a control unit configured to control the optical axis adjusting unit such that an amount of the optical axis deviation is corrected.
    Type: Grant
    Filed: March 3, 2010
    Date of Patent: December 13, 2011
    Assignee: NuFlare Technology, Inc.
    Inventors: Michihiro Sakai, Ryoichi Kakehi, Kiyoshi Hattori
  • Publication number: 20100224789
    Abstract: A charged particle beam writing apparatus includes a stage on which a target object is placed; an emitting unit configured to emit a charged particle beam to the stage side; a blocking unit arranged between the emitting unit and the stage and configured to block the charged particle beam emitted; a deflector having electrodes through which a current flows by applying a voltage and configured to deflect the charged particle beam passing between the electrodes onto the blocking unit by applying a predetermined voltage across the electrodes; an optical axis adjusting unit configured to correct optical axis deviation of the charged particle beam generated by continuously repeating irradiation (beam-ON) of the charged particle beam on a target object and blocking (beam-OFF) of the beam by applying a two-step voltage to the deflector; and a control unit configured to control the optical axis adjusting unit such that an amount of the optical axis deviation is corrected.
    Type: Application
    Filed: March 3, 2010
    Publication date: September 9, 2010
    Applicant: NuFlare Technology, Inc.
    Inventors: Michihiro Sakai, Ryoichi Kakehi, Kiyoshi Hattori