Patents by Inventor Takaho Yoshida

Takaho Yoshida 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: 10217602
    Abstract: High expectations are placed on aberration correctors to increase the resolving power of charged particle devices. Meanwhile, a far more complicated configuration and higher mechanical precision assembly in comparison to prior art aberration correctors are necessary in charged particle beam optical devices that use low-energy electron beams. A complex electromagnetic quadrupole part employed in the aberration corrector preferably has the forward extremities of the poles provided in a vacuum near an electron beam path and excitation coils disposed outside the vacuum, and this necessitates a structure that can achieve both electrical insulation and vacuum sealing for each of these poles. Such structural complexity generally conflicts with improving mechanical assembly precision.
    Type: Grant
    Filed: July 3, 2015
    Date of Patent: February 26, 2019
    Assignee: HITACHI HIGH-TECHNOLOGIES CORPORATION
    Inventor: Takaho Yoshida
  • Publication number: 20170162362
    Abstract: High expectations are placed on aberration correctors to increase the resolving power of charged particle devices. Meanwhile, a far more complicated configuration and higher mechanical precision assembly in comparison to prior art aberration correctors are necessary in charged particle beam optical devices that use low-energy electron beams. A complex electromagnetic quadrupole part employed in the aberration corrector preferably has the forward extremities of the poles provided in a vacuum near an electron beam path and excitation coils disposed outside the vacuum, and this necessitates a structure that can achieve both electrical insulation and vacuum sealing for each of these poles. Such structural complexity generally conflicts with improving mechanical assembly precision.
    Type: Application
    Filed: July 3, 2015
    Publication date: June 8, 2017
    Inventor: Takaho YOSHIDA
  • Patent number: 9484182
    Abstract: The present invention provides a method and apparatus for correcting an aberration in a charged-particle-beam device. The apparatus includes a charged-particle-beam source, a charged-particle optical system that irradiates a specimen with charged particles emitted from the charged-particle-beam source, an aberration corrector that corrects an aberration of the charged-particle optical system, a control unit that controls the charged-particle optical system and the aberration corrector, a through-focus imaging unit that obtains plural Ronchigrams in which a focal position of the charged-particle optical system is changed, and an aberration calculation unit that divides the obtained Ronchigram into plural local areas, and calculates the amount of the aberration based on line focuses detected in the local areas.
    Type: Grant
    Filed: August 7, 2013
    Date of Patent: November 1, 2016
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Hisanao Akima, Takaho Yoshida
  • Patent number: 9224574
    Abstract: Beam scanning for obtaining a scanned image is performed by an aberration corrector, which is an aberration measured lens, and a scanning coil disposed above an objective lens, instead of a scanning coil ordinarily placed on the objective lens. Thus, distortion with an aberration of an aberration measured lens is scanned on the surface of a sample, and then a scanned image is formed from a scattered electron beam, a transmission electron beam, or a reflected/secondary electron beam that is generated by the scan, achieving a scanning aberration information pattern equivalent to a conventional Ronchigram. Such means is a feature of the present invention.
    Type: Grant
    Filed: November 4, 2011
    Date of Patent: December 29, 2015
    Assignee: HITACHI HIGH-TECHNOLOGIES CORPORATION
    Inventors: Takaho Yoshida, Hisanao Akima
  • Publication number: 20150235801
    Abstract: In aberration measurement, a focus or an inclination angle of a beam is changed to extract a characteristic amount from plural images of an electron microscope, so that an aberration coefficient indicating the size and direction of aberration is obtained. However, when the aberration is extremely large, the electron microscope images are greatly distorted, which causes difficulties in extraction of the feature amount.
    Type: Application
    Filed: August 7, 2013
    Publication date: August 20, 2015
    Inventors: Hisanao Akima, Takaho Yoshida
  • Patent number: 8866078
    Abstract: Disclosed is a scanning transmission type electron microscope provided with a scanning transmission electron microscope provided with an aberration corrector 805 for correcting the aberration of an electron-optical system that irradiates electron beams to a sample (808); a bright field image detector (813) for detecting electron beams that have transmitted through the sample; a camera (814); and an information processing apparatus (703) for processing signals detected by the detectors.
    Type: Grant
    Filed: May 16, 2011
    Date of Patent: October 21, 2014
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Hisanao Akima, Takaho Yoshida
  • Publication number: 20130256531
    Abstract: Beam scanning for obtaining a scanned image is performed by an aberration corrector, which is an aberration measured lens, and a scanning coil disposed above an objective lens, instead of a scanning coil ordinarily placed on the objective lens. Thus, distortion with an aberration of an aberration measured lens is scanned on the surface of a sample, and then a scanned image is formed from a scattered electron beam, a transmission electron beam, or a reflected/secondary electron beam that is generated by the scan, achieving a scanning aberration information pattern equivalent to a conventional Ronchigram. Such means is a feature of the present invention.
    Type: Application
    Filed: November 4, 2011
    Publication date: October 3, 2013
    Applicant: HITACHI HIGH-TECHNOLOGIES CORPORATION
    Inventors: Takaho Yoshida, Hisanao Akima
  • Publication number: 20130099117
    Abstract: Disclosed is a scanning transmission type electron microscope provided with a scanning transmission electron microscope provided with an aberration corrector 805 for correcting the aberration of an electron-optical system that irradiates electron beams to a sample (808); a bright field image detector (813) for detecting electron beams that have transmitted through the sample; a camera (814); and an information processing apparatus (703) for processing signals detected by the detectors.
    Type: Application
    Filed: May 16, 2011
    Publication date: April 25, 2013
    Inventors: Hisanao Akima, Takaho Yoshida
  • Patent number: 8035086
    Abstract: To provide an aberration correction configuration that can realize both an aberration correction function for a long focus and an aberration correction function for a short focus. While having a conventional aberration correction apparatus configuration that has two rotationally symmetric lenses arranged between two multipole lenses, three rotationally symmetric lenses are disposed between an objective lens and a multipole lens instead of the conventional arrangement in which two rotationally symmetric lenses are disposed therebetween. When using the objective lens with a long focal length, aberrations are corrected using two rotationally symmetric lenses among three rotationally symmetric lenses disposed between the objective lens and the multipole lens. When using the objective lens with a short focal length, e.g.
    Type: Grant
    Filed: February 23, 2009
    Date of Patent: October 11, 2011
    Assignees: Hitachi, Ltd., Okinawa Institute of Science and Technology Promotion Corporation
    Inventors: Yoichi Hirayama, Takaho Yoshida
  • Patent number: 7825377
    Abstract: An electron beam apparatus with an aberration corrector using multipole lenses is provided. The electron beam apparatus has a scan mode for enabling the operation of the aberration corrector and a scan mode for disabling the operation of the aberration corrector and the operation of each of the aberration corrector, a condenser lens, and the like is controlled such that the object point of an objective lens does not change in either of the scan modes. If a comparison is made between the secondary electron images of a specimen in the two modes, the image scaling factor and the focus remain unchanged and evaluation and adjustment can be performed by distinctly recognizing only the effect of the aberration corrector. This reduces the time required to adjust an optical axis which has been long due to an axial alignment defect inherent in the aberration corrector and an axial alignment defect in a part other than the aberration corrector which are indistinguishably intermingled with each other.
    Type: Grant
    Filed: May 13, 2008
    Date of Patent: November 2, 2010
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Takeshi Kawasaki, Takaho Yoshida, Yoichi Ose, Hideo Todokoro
  • Patent number: 7732766
    Abstract: A crystal thin film is adopted as a specimen for measurement. A change in the contrast of crystal lattice fringes is measured under a condition that a diffracted wave and other wave are caused to interfere with each other. Thus, an information transfer limit of a transmission electron microscope can be measured quantitatively. Since the measurement is performed with a condition for interference restricted, the information transfer limit of the transmission electron microscope can be quantitatively assessed.
    Type: Grant
    Filed: October 26, 2007
    Date of Patent: June 8, 2010
    Assignee: Hitachi, Ltd.
    Inventor: Takaho Yoshida
  • Patent number: 7619218
    Abstract: When an accelerating voltage and operating distance are changed, an excitation current and a pole voltage of an aberration corrector must also be changed. Moreover, different multipole voltages or currents must be added individually for each pole in order to superpose multipoles.
    Type: Grant
    Filed: January 29, 2007
    Date of Patent: November 17, 2009
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Tomonori Nakano, Takaho Yoshida
  • Publication number: 20090242786
    Abstract: To provide an aberration corrector that guarantees freedom in designing a coma-free plane transfer portion even when the mechanical configuration of the aberration corrector is already decided, and has a flexible adjustment margin regarding the corrector exterior. The aberration corrector causes an electron beam trajectory emanating from a specimen plane (physical surface of objective lens) to be incident in parallel with a multipole lens (HEX1 18), and causes an electron beam trajectory emanating from an objective-lens coma-free plane or a minimum plane of a fifth-order aberration (objective lens center) to form an image on a center plane of a multipole lens of the 4f system. Thus, antisymmetric transfer is performed between two multipole lenses (HEX1 18, HEX2 19) to correct a spherical aberration in the 4f system, and a coma-free plane or a minimum plane of a fifth-order aberration is transferred to suppress occurrence of coma aberrations or fifth-order aberrations. (See FIG.
    Type: Application
    Filed: March 2, 2009
    Publication date: October 1, 2009
    Inventors: Takaho Yoshida, Yoichi Hirayama
  • Publication number: 20090230317
    Abstract: To provide an aberration correction configuration that can realize both an aberration correction function for a long focus and an aberration correction function for a short focus. While having a conventional aberration correction apparatus configuration that has two rotationally symmetric lenses arranged between two multiple lenses, three rotationally symmetric lenses are disposed between an objective lens and a multiple lens instead of the conventional arrangement in which two rotationally symmetric lenses are disposed therebetween. When using the objective lens with a long focal length, aberrations are corrected using two rotationally symmetric lenses among three rotationally symmetric lenses disposed between the objective lens and the multiple lens. When using the objective lens with a short focal length, e.g.
    Type: Application
    Filed: February 23, 2009
    Publication date: September 17, 2009
    Inventors: Yoichi Hirayama, Takaho Yoshida
  • Patent number: 7531799
    Abstract: A scanning electron microscope includes an electron gun to generate an electron beam, and an electron optical system directing the electron beam to a specimen. The electron optical system includes an objective lens that converges the electron beam to a surface of the specimen, an aberration corrector disposed between the electron gun and the objective lens so as to at least compensate for aberration caused by the objective lens, and a tilter which tilts electron beam to be incident into the aberration corrector. The aberration corrector further compensates for aberration caused by the tilter.
    Type: Grant
    Filed: May 22, 2007
    Date of Patent: May 12, 2009
    Inventors: Takeshi Kawasaki, Takaho Yoshida, Tomonori Nakano
  • Publication number: 20090008551
    Abstract: An electron beam apparatus with an aberration corrector using multipole lenses is provided. The electron beam apparatus has a scan mode for enabling the operation of the aberration corrector and a scan mode for disabling the operation of the aberration corrector and the operation of each of the aberration corrector, a condenser lens, and the like is controlled such that the object point of an objective lens does not change in either of the scan modes. If a comparison is made between the secondary electron images of a specimen in the two modes, the image scaling factor and the focus remain unchanged and evaluation and adjustment can be performed by distinctly recognizing only the effect of the aberration corrector. This reduces the time required to adjust an optical axis which has been long due to an axial alignment defect inherent in the aberration corrector and an axial alignment defect in a part other than the aberration corrector which are indistinguishably intermingled with each other.
    Type: Application
    Filed: May 13, 2008
    Publication date: January 8, 2009
    Inventors: Takeshi Kawasaki, Takaho Yoshida, Yoichi Ose, Hideo Todokoro
  • Patent number: 7375323
    Abstract: An electron beam apparatus with an aberration corrector using multipole lenses is provided. The electron beam apparatus has a scan mode for enabling the operation of the aberration corrector and a scan mode for disabling the operation of the aberration corrector and the operation of each of the aberration corrector, a condenser lens, and the like is controlled such that the object point of an objective lens does not change in either of the scan modes. If a comparison is made between the secondary electron images of a specimen in the two modes, the image scaling factor and the focus remain unchanged and evaluation and adjustment can be performed by distinctly recognizing only the effect of the aberration corrector. This reduces the time required to adjust an optical axis which has been long due to an axial alignment defect inherent in the aberration corrector and an axial alignment defect in a part other than the aberration corrector which are indistinguishably intermingled with each other.
    Type: Grant
    Filed: January 22, 2007
    Date of Patent: May 20, 2008
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Takeshi Kawasaki, Takaho Yoshida, Yoichi Ose, Hideo Todokoro
  • Publication number: 20080099677
    Abstract: A crystal thin film is adopted as a specimen for measurement. A change in the contrast of crystal lattice fringes is measured under a condition that a diffracted wave and other wave are caused to interfere with each other. Thus, an information transfer limit of a transmission electron microscope can be measured quantitatively. Since the measurement is performed with a condition for interference restricted, the information transfer limit of the transmission electron microscope can be quantitatively assessed.
    Type: Application
    Filed: October 26, 2007
    Publication date: May 1, 2008
    Inventor: Takaho YOSHIDA
  • Patent number: 7319225
    Abstract: A transmission electron microscope has a means for inputting a spatial size or distance d desired to be observed by the operator, calculates high contrast of an image based on this value and an observing condition which can reduce the influence of a false image superimposed, and desirably modulates an accelerating voltage of the electron microscope based thereon.
    Type: Grant
    Filed: February 17, 2006
    Date of Patent: January 15, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Hiroto Kasai, Takaho Yoshida
  • Publication number: 20070221860
    Abstract: A scanning electron microscope includes an electron gun to generate an electron beam, and an electron optical system directing the electron beam to a specimen. The electron optical system includes an objective lens that converges the electron beam to a surface of the specimen, an aberration corrector disposed between the electron gun and the objective lens so as to at least compensate for aberration caused by the objective lens, and a tilter which tilts electron beam to be incident into the aberration corrector. The aberration corrector further compensates for aberration caused by the tilter.
    Type: Application
    Filed: May 22, 2007
    Publication date: September 27, 2007
    Inventors: Takeshi Kawasaki, Takaho Yoshida, Tomonori Nakano