Patents by Inventor Tsubasa NANAO

Tsubasa NANAO 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: 11804360
    Abstract: The present invention quickly calculates values of optimal excitation parameters which are set in lenses in multiple stages. A multi charged particle beam adjustment method includes forming a multi charged particle beam, calculating, for each of lenses in two or more stages disposed corresponding to object lenses in two or more stages, a first rate of change and a second rate of change in response to change in at least an excitation parameter, the first rate of change being a rate of change in a demagnification level of a beam image of the multi charged particle beam, the second rate of change being a rate of change in a rotation level of the beam image, and calculating a first amount of correction to the excitation parameter of each of the lenses based on an amount of correction to the demagnification level and the rotation level of the beam image, the first rate of change, and the second rate of change.
    Type: Grant
    Filed: November 4, 2020
    Date of Patent: October 31, 2023
    Assignee: NuFlare Technology, Inc.
    Inventors: Tsubasa Nanao, Hirofumi Morita, Takanao Touya
  • Patent number: 11740546
    Abstract: In one embodiment, a multi charged particle beam writing apparatus includes an objective lens adjusting focus positions of multiple beams, an astigmatism correction element correcting astigmatism of the multiple beams, an inspection aperture allowing one of the multiple beams to pass therethrough, a deflector deflecting the multiple beams and causing the multiple beams to scan over the inspection aperture, a current detector detecting beam currents of the individual multiple beams after passing through the inspection aperture, a beam image formation unit forming a beam image based on the detected beam currents, a feature amount calculation unit generating a first waveform and a second waveform by adding brightnesses of the beam image in a first direction and in a second direction, and calculating a first and a second feature amounts from the first and the second waveforms, and a parameter calculation unit calculating an exciting parameter that is to be set for the astigmatism correction element based on the f
    Type: Grant
    Filed: March 7, 2022
    Date of Patent: August 29, 2023
    Assignee: NuFlare Technology, Inc.
    Inventors: Tsubasa Nanao, Hiroshi Matsumoto
  • Publication number: 20230005711
    Abstract: The present invention quickly calculates values of optimal excitation parameters which are set in lenses in multiple stages. A multi charged particle beam adjustment method includes forming a multi charged particle beam, calculating, for each of lenses in two or more stages disposed corresponding to object lenses in two or more stages, a first rate of change and a second rate of change in response to change in at least an excitation parameter, the first rate of change being a rate of change in a demagnification level of a beam image of the multi charged particle beam, the second rate of change being a rate of change in a rotation level of the beam image, and calculating a first amount of correction to the excitation parameter of each of the lenses based on an amount of correction to the demagnification level and the rotation level of the beam image, the first rate of change, and the second rate of change.
    Type: Application
    Filed: November 4, 2020
    Publication date: January 5, 2023
    Applicant: NuFlare Technology, Inc.
    Inventors: Tsubasa NANAO, Hirofumi MORITA, Takana TOUYA
  • Publication number: 20220359156
    Abstract: The mark position is measured with a multi-beam with high accuracy. A multi charged particle beam writing method includes forming a multi-beam (30a-30e) in which charged particle beams are arranged with a predetermined pitch, irradiating a mark (M) with beams in an on-beam region while shifting irradiation positions of the charged particle beams by sequentially changing the on-beam region in which beams in a partial region of the multi-beam (30a-30e) are set to ON, the mark (M) being provided at a predetermined position and having a width greater than the predetermined pitch, detecting a reflected charged particle signal from the mark (M), and calculating a position of the mark (M), and adjusting the irradiation positions of the multi-beam based on the calculated position of the mark (M), and writing a pattern.
    Type: Application
    Filed: July 15, 2022
    Publication date: November 10, 2022
    Applicant: NuFlare Technology, Inc.
    Inventors: Tsubasa NANAO, Osamu IIZUKA
  • Publication number: 20220299861
    Abstract: In one embodiment, a multi charged particle beam writing apparatus includes an objective lens adjusting focus positions of multiple beams, an astigmatism correction element correcting astigmatism of the multiple beams, an inspection aperture allowing one of the multiple beams to pass therethrough, a deflector deflecting the multiple beams and causing the multiple beams to scan over the inspection aperture, a current detector detecting beam currents of the individual multiple beams after passing through the inspection aperture, a beam image formation unit forming a beam image based on the detected beam currents, a feature amount calculation unit generating a first waveform and a second waveform by adding brightnesses of the beam image in a first direction and in a second direction, and calculating a first and a second feature amounts from the first and the second waveforms, and a parameter calculation unit calculating an exciting parameter that is to be set for the astigmatism correction element based on the f
    Type: Application
    Filed: March 7, 2022
    Publication date: September 22, 2022
    Applicant: NuFlare Technology, Inc.
    Inventors: Tsubasa NANAO, Hiroshi MATSUMOTO
  • Patent number: 10490388
    Abstract: A multibeam-focus adjusting method in a charged-particle-beam lithography apparatus that draws a pattern by irradiating a sample with multibeams having a plurality of beam lines through a plurality of lines of opening portions provided on an aperture member, the method adjusting a focus of the multibeams and including: acquiring a rotation angle of the beam lines with respect to an end edge of a mark provided at a predetermined position; determining selection beams to be used for adjustment among the multibeams based on the acquired rotation angle; and adjusting a focus of the multibeams based on reflected electrons acquired by irradiating the mark with the selection beams and scanning the mark in a direction orthogonal to the end edge of the mark.
    Type: Grant
    Filed: October 17, 2017
    Date of Patent: November 26, 2019
    Assignee: NUFLARE TECHNOLOGY, INC.
    Inventor: Tsubasa Nanao
  • Patent number: 10388488
    Abstract: In one embodiment, a multi charged particle beam drawing apparatus includes an emitter emitting a charged particle beam, a shaping aperture array in which a plurality of first openings are formed, and which receives irradiation of the charged particle beam in an area including the plurality of first openings, and forms a multi-beam by allowing part of the charged particle beam to pass through a corresponding one of the plurality of first openings, a blanking aperture array in which a plurality of second openings are formed, through each of which a beam is passed, corresponding to part of the multi-beam which has passed through the plurality of first openings, the plurality of second openings each including a blanker that performs blanking deflection of a beam, and a movement controller moving the shaping aperture array or the blanking aperture array, and adjusting space between the shaping aperture array and the blanking aperture array.
    Type: Grant
    Filed: May 30, 2018
    Date of Patent: August 20, 2019
    Assignee: NuFlare Technology, Inc.
    Inventors: Hirofumi Morita, Osamu Iizuka, Tsubasa Nanao
  • Patent number: 10157723
    Abstract: In one embodiment, a multi charged particle beam writing apparatus includes an emitter that emits a charged particle beam, an aperture plate in which a plurality of openings are formed and that forms multiple beams by allowing the charged particle beam to pass through the plurality of openings, a blanking plate provided with a plurality of blankers that each perform blanking deflection on a corresponding beam included in the multiple beams, a stage on which a substrate irradiated with the multiple beams, a detector that detects a reflection charged particle from the substrate, feature amount calculation circuitry that calculates a feature amount of an aperture image based on a detection value of the detector, and aberration correction circuitry that corrects aberration of the charged particle beam based on the feature amount.
    Type: Grant
    Filed: August 1, 2017
    Date of Patent: December 18, 2018
    Assignee: NuFlare Technology, Inc.
    Inventors: Tsubasa Nanao, Yukitaka Shimizu
  • Publication number: 20180350552
    Abstract: In one embodiment, a multi charged particle beam drawing apparatus includes an emitter emitting a charged particle beam, a shaping aperture array in which a plurality of first openings are formed, and which receives irradiation of the charged particle beam in an area including the plurality of first openings, and forms a multi-beam by allowing part of the charged particle beam to pass through a corresponding one of the plurality of first openings, a blanking aperture array in which a plurality of second openings are formed, through each of which a beam is passed, corresponding to part of the multi-beam which has passed through the plurality of first openings, the plurality of second openings each including a blanker that performs blanking deflection of a beam, and a movement controller moving the shaping aperture array or the blanking aperture array, and adjusting space between the shaping aperture array and the blanking aperture array,
    Type: Application
    Filed: May 30, 2018
    Publication date: December 6, 2018
    Applicant: NuFlare Technology, Inc.
    Inventors: Hirofumi MORITA, Osamu Iizuka, Tsubasa Nanao
  • Patent number: 10042261
    Abstract: In one embodiment, a method of aperture alignment for a multi charged particle beam writing apparatus includes irradiating a shaping aperture member with a charged particle beam while changing an incident direction, detecting a current for each of the incident directions of the charged particle beam, producing a current distribution map based on the incident direction and the current, and moving the shaping aperture member or a blanking aperture member based on the current distribution map to align the shaping aperture member with the blanking aperture member.
    Type: Grant
    Filed: November 2, 2016
    Date of Patent: August 7, 2018
    Assignee: NuFlare Technology, Inc.
    Inventor: Tsubasa Nanao
  • Publication number: 20180108511
    Abstract: A multibeam-focus adjusting method in a charged-particle-beam lithography apparatus that draws a pattern by irradiating a sample with multibeams having a plurality of beam lines through a plurality of lines of opening portions provided on an aperture member, the method adjusting a focus of the multibeams and including: acquiring a rotation angle of the beam lines with respect to an end edge of a mark provided at a predetermined position; determining selection beams to be used for adjustment among the multibeams based on the acquired rotation angle; and adjusting a focus of the multibeams based on reflected electrons acquired by irradiating the mark with the selection beams and scanning the mark in a direction orthogonal to the end edge of the mark.
    Type: Application
    Filed: October 17, 2017
    Publication date: April 19, 2018
    Applicant: NUFLARE TECHNOLOGY, INC.
    Inventor: Tsubasa NANAO
  • Publication number: 20180040453
    Abstract: In one embodiment, a multi charged particle beam writing apparatus includes an emitter that emits a charged particle beam, an aperture plate in which a plurality of openings are formed and that forms multiple beams by allowing the charged particle beam to pass through the plurality of openings, a blanking plate provided with a plurality of blankers that each perform blanking deflection on a corresponding beam included in the multiple beams, a stage on which a substrate irradiated with the multiple beams, a detector that detects a reflection charged particle from the substrate, feature amount calculation circuitry that calculates a feature amount of an aperture image based on a detection value of the detector, and aberration correction circuitry that corrects aberration of the charged particle beam based on the feature amount.
    Type: Application
    Filed: August 1, 2017
    Publication date: February 8, 2018
    Applicant: NuFlare Technology, Inc.
    Inventors: Tsubasa NANAO, Yukitaka Shimizu
  • Publication number: 20170146910
    Abstract: In one embodiment, a method of aperture alignment for a multi charged particle beam writing apparatus includes irradiating a shaping aperture member with a charged particle beam while changing an incident direction, detecting a current for each of the incident directions of the charged particle beam, producing a current distribution map based on the incident direction and the current, and moving the shaping aperture member or a blanking aperture member based on the current distribution map to align the shaping aperture member with the blanking aperture member.
    Type: Application
    Filed: November 2, 2016
    Publication date: May 25, 2017
    Applicant: NUFLARE TECHNOLOGY, INC.
    Inventor: Tsubasa NANAO