Patents by Inventor Kenji Ohtoshi

Kenji Ohtoshi 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: 9653262
    Abstract: A method of measuring beam positions of multi charged particle beams includes acquiring a number of multi charged particle beams needed for the measurement reproducibility of a current amount to be within the range of an allowable value. The method further includes setting measurement points depending on a desired dimensional accuracy value in an irradiation region irradiated by the whole of the multi charged particle beams, and setting, for each of a plurality of measurement points, a beam region, including a measurement point of measurement points irradiated by a plurality of beams whose number is the number of beams needed for the measurement reproducibility in the multi charged particle beams. Further, the method includes measuring, for each of a plurality of measurement points, the position of a measurement point concerned in a plurality of measurement points by using a plurality of beams of a corresponding beam region.
    Type: Grant
    Filed: August 11, 2015
    Date of Patent: May 16, 2017
    Assignee: NuFlare Technology, Inc.
    Inventors: Osamu Iizuka, Kenji Ohtoshi
  • Patent number: 9472372
    Abstract: A charged particle beam writing apparatus includes a stage configured to mount a sample placed thereon; an electron optical column including a charged particle gun and deflector, wherein the charged particle gun is configured to emit a charged particle beam, and the deflector includes a plurality of deflecting electrodes configured to control a path of the charged particle beam; an ozone introducing mechanism configured to introduce ozone into the electron optical column; a first voltage supply unit configured to apply a deflection voltage to the plurality of deflecting electrodes to deflect the charged particle beam; and a second voltage supply unit configured to apply an identical negative DC voltage to the plurality of deflecting electrodes, wherein a negative voltage in which the deflection voltage and the negative DC voltage are added is applied to the plurality of deflecting electrodes while the sample is irradiated by the charged particle beam.
    Type: Grant
    Filed: July 14, 2015
    Date of Patent: October 18, 2016
    Assignee: NuFlare Technology, Inc.
    Inventors: Taku Yamada, Kaoru Tsuruta, Yasuyuki Taneda, Kenji Ohtoshi
  • Patent number: 9466461
    Abstract: According to one aspect of the present invention, a rotation angle measuring method of a multi-charged particle beam image includes two-dimensionally scanning a mark arranged on a stage in a multi-charged particle beam writing apparatus using, among multi-charged particle beams that can be used for exposure, a plurality of representative beams of which number is smaller than the number of beams constituting the multi-charged particle beams, creating a two-dimensional image of the plurality of representative beams based on signals obtained by two-dimensional scanning, and acquiring a rotation angle of the multi-charged particle beam image using the two-dimensional image.
    Type: Grant
    Filed: December 15, 2015
    Date of Patent: October 11, 2016
    Assignee: NuFlare Technology, Inc.
    Inventors: Osamu Iizuka, Kenji Ohtoshi
  • Publication number: 20160211111
    Abstract: According to one aspect of the present invention, a rotation angle measuring method of a multi-charged particle beam image includes two-dimensionally scanning a mark arranged on a stage in a multi-charged particle beam writing apparatus using, among multi-charged particle beams that can be used for exposure, a plurality of representative beams of which number is smaller than the number of beams constituting the multi-charged particle beams, creating a two-dimensional image of the plurality of representative beams based on signals obtained by two-dimensional scanning, and acquiring a rotation angle of the multi-charged particle beam image using the two-dimensional image.
    Type: Application
    Filed: December 15, 2015
    Publication date: July 21, 2016
    Applicant: NuFlare Technology, Inc.
    Inventors: Osamu IIZUKA, Kenji OHTOSHI
  • Publication number: 20160086764
    Abstract: A method of measuring beam positions of multi charged particle beams includes acquiring the number of beams of multi charged particle beams, needed for the measurement reproducibility of a current amount to be within the range of an allowable value, setting a plurality of measurement points depending on a desired dimensional accuracy value, in an irradiation region irradiated by the whole of the multi charged particle beams, setting, for each of a plurality of measurement points, a beam region, including a measurement point of a plurality of measurement points, irradiated by a plurality of beams whose number is the number of beams needed for the measurement reproducibility in the multi charged particle beams, and measuring, for each of a plurality of measurement points, the position of a measurement point concerned in a plurality of measurement points by using a plurality of beams of a corresponding beam region.
    Type: Application
    Filed: August 11, 2015
    Publication date: March 24, 2016
    Applicant: NuFlare Technology, Inc.
    Inventors: Osamu IIZUKA, Kenji OHTOSHI
  • Publication number: 20160020063
    Abstract: A charged particle beam writing apparatus includes a stage configured to mount a sample placed thereon; an electron optical column including a charged particle gun and deflector, wherein the charged particle gun is configured to emit a charged particle beam, and the deflector includes a plurality of deflecting electrodes configured to control a path of the charged particle beam; an ozone introducing mechanism configured to introduce ozone into the electron optical column; a first voltage supply unit configured to apply a deflection voltage to the plurality of deflecting electrodes to deflect the charged particle beam; and a second voltage supply unit configured to apply an identical negative DC voltage to the plurality of deflecting electrodes, wherein a negative voltage in which the deflection voltage and the negative DC voltage are added is applied to the plurality of deflecting electrodes while the sample is irradiated by the charged particle beam.
    Type: Application
    Filed: July 14, 2015
    Publication date: January 21, 2016
    Applicant: NuFlare Technology, Inc.
    Inventors: Taku Yamada, Kaoru Tsuruta, Yasuyuki Taneda, Kenji Ohtoshi
  • Patent number: 9190245
    Abstract: A charged particle beam writing apparatus includes an emission unit to emit a charged particle beam, a stage to mount thereon a target object to be written, an objective lens to focus the charged particle beam on a surface of the target object, a chamber to house the stage, a measurement unit to measure a partial pressure of a predetermined gas in the chamber in a state where a pressure inside the chamber is controlled to be lower than an atmospheric pressure, and an adjustment unit to adjust a focus position for focusing the charged particle beam on the target object, based on the partial pressure of the predetermined gas.
    Type: Grant
    Filed: January 28, 2015
    Date of Patent: November 17, 2015
    Assignee: NuFlare Technology, Inc.
    Inventors: Tomoo Motosugi, Takayuki Ohnishi, Kaoru Tsuruta, Kenji Ohtoshi
  • Publication number: 20150228455
    Abstract: A charged particle beam writing apparatus includes an emission unit to emit a charged particle beam, a stage to mount thereon a target object to be written, an objective lens to focus the charged particle beam on a surface of the target object, a chamber to house the stage, a measurement unit to measure a partial pressure of a predetermined gas in the chamber in a state where a pressure inside the chamber is controlled to be lower than an atmospheric pressure, and an adjustment unit to adjust a focus position for focusing the charged particle beam on the target object, based on the partial pressure of the predetermined gas.
    Type: Application
    Filed: January 28, 2015
    Publication date: August 13, 2015
    Applicant: NuFlare Technology, Inc.
    Inventors: Tomoo MOTOSUGI, Takayuki OHNISHI, Kaoru TSURUTA, Kenji OHTOSHI
  • Patent number: 8253112
    Abstract: A lithography apparatus includes a unit irradiating a charged particle beam; first and second aperture plate members configured to shape the beam; first and second coils configured to be arranged between the unit and the first aperture plate member, to temporarily deflect the beam, to change a direction of the beam after the temporarily deflecting, and to deflect the beam to a position where the beam passes through the first aperture plate member by the changing; a lens configured to be arranged between the first and second aperture plate members and to control a focal position of the beam having passed through the first aperture plate member; and a unit configured to calculate a difference between positions of the beam on the second aperture plate member obtained by different sets of amounts of deflection at a same focal position when a combination of one of focal positions of the beam controlled by the lens and one of sets of amounts of deflection of the beam obtained by the first and second coils is change
    Type: Grant
    Filed: June 23, 2009
    Date of Patent: August 28, 2012
    Assignee: Nuflare Technology, Inc.
    Inventors: Osamu Iizuka, Kenji Ohtoshi
  • Patent number: 8188443
    Abstract: A focusing method of a charged particle beam includes measuring a first set value to focus a beam on a position of a reference plane by using a lens coil, acquiring a first factor to change a set value of an electrostatic lens depending on a distance and a second factor to change a set value of the coil depending on a distance, measuring a level distribution of a target plane, correcting the first set value by using the second factor to correct a focal point position of the beam in the coil from the position of the reference plane to an intermediate level position of the level distribution of the target plane, and correcting a second set value of the lens depending on a level position of the target plane by using the first factor to correct a focal point position of the beam by the lens.
    Type: Grant
    Filed: March 6, 2008
    Date of Patent: May 29, 2012
    Assignee: NuFlare Technology, Inc.
    Inventors: Kenji Ohtoshi, Hitoshi Sunaoshi, Osamu Iizuka, Takahito Nakayama
  • Patent number: 8008631
    Abstract: A method of acquiring an offset deflection amount for a shaped beam, includes forming reference images of first and second figures which can be shaped by first and second aperture plates placed on a lithography apparatus, and a reference image of a mark; forming first and second convolution reference images based on the reference images of the mark and of the first and second figures; scanning over the mark with charged particle beams shaped into the first and second figures to acquire optical images of the first and second figures; forming first and second convolution synthesis images based on the first convolution reference image and respectively the optical images of the first and second figures; and calculating an offset deflection amount for the charged particle beam shaped into the second figure to match reference positions of the first and second figures based on center-of-gravity positions of the first and second convolution synthesis images.
    Type: Grant
    Filed: June 30, 2009
    Date of Patent: August 30, 2011
    Assignee: NuFlare Technology, Inc.
    Inventors: Takahito Nakayama, Kenji Ohtoshi, Osamu Iizuka, Shunji Shinkawa
  • Patent number: 7679068
    Abstract: A method of obtaining a deflection aberration correcting voltage. The method includes writing predetermined patterns at a plurality of focus height positions such that a dose is used as a variable. Dimensional variations of width sizes of the predetermined patterns written at the plurality of focus height positions such that the dose is used as the variable are measured. Further, effective resolutions of the written predetermined patterns are calculated by using the dimensional variations. The method further includes, on the basis of a focus height position at which a minimum effective resolution of the predetermined patterns is obtained, calculating a correcting voltage to correct deflection aberration and outputting the correcting voltage. The correcting voltage is used when a charged particle beam is deflected.
    Type: Grant
    Filed: December 28, 2006
    Date of Patent: March 16, 2010
    Assignee: NuFlare Technology, Inc.
    Inventors: Takashi Kamikubo, Shuichi Tamamushi, Hitoshi Sunaoshi, Kenji Ohtoshi, Rieko Nishimura
  • Publication number: 20100001203
    Abstract: A method of acquiring an offset deflection amount for a shaped beam, includes forming reference images of first and second figures which can be shaped by first and second aperture plates placed on a lithography apparatus; forming, using design data of a mark, a reference image of the mark; forming a first convolution reference image obtained by a convolution calculation of the reference image of the mark and the reference image of the first figure and a second convolution reference image obtained by a convolution calculation of the reference image of the mark and the reference image of the second figure; respectively scanning over the mark with charged particle beams having shaped into the first and second figures by using the first and second aperture plates to acquire optical images of the first and second figures; forming a first convolution synthesis image obtained by a convolution calculation of the first convolution reference image and the optical image of the first figure and a second convolution synth
    Type: Application
    Filed: June 30, 2009
    Publication date: January 7, 2010
    Applicant: NuFlare Technology, Inc.
    Inventors: Takahito Nakayama, Kenji Ohtoshi, Osamu Iizuka, Shunji Shinkawa
  • Publication number: 20090314950
    Abstract: A lithography apparatus includes a unit irradiating a charged particle beam; first and second aperture plate members configured to shape the beam; first and second coils configured to be arranged between the unit and the first aperture plate member, to temporarily deflect the beam, to change a direction of the beam after the temporarily deflecting, and to deflect the beam to a position where the beam passes through the first aperture plate member by the changing; a lens configured to be arranged between the first and second aperture plate members and to control a focal position of the beam having passed through the first aperture plate member; and a unit configured to calculate a difference between positions of the beam on the second aperture plate member obtained by different sets of amounts of deflection at a same focal position when a combination of one of focal positions of the beam controlled by the lens and one of sets of amounts of deflection of the beam obtained by the first and second coils is change
    Type: Application
    Filed: June 23, 2009
    Publication date: December 24, 2009
    Applicant: NuFlare Technology, Inc.
    Inventors: Osamu IIZUKA, Kenji Ohtoshi
  • Patent number: 7521689
    Abstract: A deflector for an equipment of electron beam lithography, the deflector including a plurality of control electrodes arranged symmetrically relative to the center axis of an irradiated electron beam, the electrodes configured to control the electron beam by applying voltages respectively, a plurality of molding substrates arranged symmetrically relative to the center axis of the electron beam configured to face outer peripheral surfaces of the plurality of control electrodes and a plurality of earth electrodes arranged respectively at the plurality of molding substrates. The deflector can suppress generation of cross talks with an improved accuracy of controlling an electron beam.
    Type: Grant
    Filed: February 5, 2007
    Date of Patent: April 21, 2009
    Assignee: NuFlare Technology, Inc.
    Inventors: Yoshimasa Sanmiya, Kenji Ohtoshi, Tetsuro Nishiyama
  • Patent number: 7476881
    Abstract: There is provided a charged beam drawing apparatus which includes main/sub two-stage deflectors, divides a main deflection drawing region on a sample into sub deflection drawing regions determined by the deflection width of the sub deflector, selects one of the sub deflection drawing regions by use of the main deflector and draws shots in the selected sub deflection drawing region by use of the sub deflector. A sub deflection driving unit includes a sub deflection sensitivity correction circuit, a sub deflection astigmatic correction circuit, an adder circuit which adds an output of the sub deflection sensitivity correction circuit and an output of the sub deflection astigmatic correction circuit, and a deflection amplifier which additionally applies an output of the adder circuit to the sub deflector.
    Type: Grant
    Filed: November 15, 2006
    Date of Patent: January 13, 2009
    Assignee: NuFlare Technology, Inc.
    Inventors: Kiyoshi Hattori, Kenji Ohtoshi, Tomohiro Iijima, Yoshiaki Onimaru, Hayato Kimura, Tateki Watanabe
  • Publication number: 20080217553
    Abstract: A focusing method of a charged particle beam includes measuring a first set value to focus a beam on a position of a reference plane by using a lens coil, acquiring a first factor to change a set value of an electrostatic lens depending on a distance and a second factor to change a set value of the coil depending on a distance, measuring a level distribution of a target plane, correcting the first set value by using the second factor to correct a focal point position of the beam in the coil from the position of the reference plane to an intermediate level position of the level distribution of the target plane, and correcting a second set value of the lens depending on a level position of the target plane by using the first factor to correct a focal point position of the beam by the lens.
    Type: Application
    Filed: March 6, 2008
    Publication date: September 11, 2008
    Applicant: NuFlare Technology, Inc.
    Inventors: Kenji Ohtoshi, Hitoshi Sunaoshi, Osamu Iizuka, Takahito Nakayama
  • Publication number: 20070181819
    Abstract: A deflector for an equipment of electron beam lithography, the deflector including a plurality of control electrodes arranged symmetrically relative to the center axis of an irradiated electron beam, the electrodes configured to control the electron beam by applying voltages respectively, a plurality of molding substrates arranged symmetrically relative to the center axis of the electron beam configured to face outer peripheral surfaces of the plurality of control electrodes and a plurality of earth electrodes arranged respectively at the plurality of molding substrates. The deflector can suppress generation of cross talks with an improved accuracy of controlling an electron beam.
    Type: Application
    Filed: February 5, 2007
    Publication date: August 9, 2007
    Applicant: NuFlare Technology, Inc.
    Inventors: Yoshimasa SANMIYA, Kenji Ohtoshi, Tetsuro Nishiyama
  • Publication number: 20070158576
    Abstract: A method of calculating a deflection aberration correcting voltage includes writing predetermined patterns at a plurality of focus height positions measuring dimensional variations of width sizes of the predetermined patterns written at the plurality of focus height positions, calculating effective resolutions of the written predetermined patterns by using the dimensional variations, and on the basis of a focus height position at which a minimum effective resolution of the predetermined patterns is obtained, calculating a correcting voltage to correct deflection aberration and output the correcting voltage, wherein the correcting voltage is used when a charged particle beam is deflected.
    Type: Application
    Filed: December 28, 2006
    Publication date: July 12, 2007
    Applicant: NuFlare Technology, Inc.
    Inventors: Takashi Kamikubo, Shuichi Tamamushi, Hitoshi Sunaoshi, Kenji Ohtoshi, Rieko Nishimura
  • Publication number: 20070114461
    Abstract: There is provided a charged beam drawing apparatus which includes main/sub two-stage deflectors, divides a main deflection drawing region on a sample into sub deflection drawing regions determined by the deflection width of the sub deflector, selects one of the sub deflection drawing regions by use of the main deflector and draws shots in the selected sub deflection drawing region by use of the sub deflector. A sub deflection driving unit includes a sub deflection sensitivity correction circuit, a sub deflection astigmatic correction circuit, an adder circuit which adds an output of the sub deflection sensitivity correction circuit and an output of the sub deflection astigmatic correction circuit, and a deflection amplifier which additionally applies an output of the adder circuit to the sub deflector.
    Type: Application
    Filed: November 15, 2006
    Publication date: May 24, 2007
    Inventors: Kiyoshi HATTORI, Kenji Ohtoshi, Tomohiro Iijima, Yoshiaki Onimaru, Hayato Kimura, Tateki Watanabe