公开(公告)号：US20210233741A1

公开(公告)日：2021-07-29

申请号：US17263017

申请日：2019-07-26

Applicant: RIKEN ,  UNIVERSITY PUBLIC CORPORATION OSAKA

Inventor： Ken Harada ,  Keiko Shimada ,  Shigeo Mori ,  Atsuhiro Kotani

IPC: H01J37/26 ,  H01J37/22 ,  G01N23/201 ,  H01J37/147 ,  H01J37/20 ,  H01J37/09 ,  H01J37/10

Abstract: An observation apparatus and method that avoids drawbacks of a Lorentz method and observes a weak scatterer or a phase object with in-focus, high resolution, and no azimuth dependency, by a Foucault method observation using a hollow-cone illumination that orbits and illuminates an incident electron beam having a predetermined inclination angle, an electron wave is converged at a position (height) of an aperture plate downstream of a sample and a bright field condition in which a direct transmitted electron wave of the sample passes through the aperture plate, a dark field condition in which the transmitted electron wave is shielded and a Schlieren condition in which approximately half of the transmitted wave is shielded as a boundary condition of both of the above conditions are controlled, and a spatial resolution of the observation image is controlled by selecting multiple diameters and shapes of the opening of the aperture plate.

公开(公告)号：US10948426B2

公开(公告)日：2021-03-16

申请号：US16094839

申请日：2017-04-06

Applicant: RIKEN

Inventor： Ken Harada ,  Keiko Shimada ,  Kodai Niitsu

IPC: G01N23/04 ,  H01J37/295 ,  G02B5/18 ,  H01J37/10 ,  H01J37/20 ,  H01J37/244 ,  H01J37/26

Abstract: The density difference of particle beam irradiation with two optical statuses is produced utilizing a diffraction effect, within the same field of vision, such that a diffraction grating manufactured with a material which passes through a particle beam is provided on the upper side of a specimen and on the lower side of the irradiation optical system. Further, a region wider than the opening region of the diffraction grating is irradiated with the particle beam to produce the density difference of the particle beam emitted to the specimen, by superposing the particle beam, Bragg-diffracted with the opening region, and the particle beam, transmitted through the outer peripheral part of the opening region without being diffracted, with each other, and emitting the beam to the specimen.

公开(公告)号：US11024482B2

公开(公告)日：2021-06-01

申请号：US16497738

申请日：2018-03-22

Applicant: RIKEN

Inventor： Ken Harada ,  Kodai Niitsu ,  Keiko Shimada

IPC: H01J37/22 ,  G03H1/00 ,  G03H1/04 ,  G03H1/16 ,  H01J37/20 ,  H01J37/295

Abstract: A lensless Fourier transform holography high accuracy reconstruction method using a charged particle beam apparatus which holds a sample on a diffraction surface of a diffraction grating provided on the downstream side of a traveling direction of the charged particle beam and which is formed of a material having permeability. The charged particle beam passed through the diffraction surface is image-formed, and the formed image is detected. An opening region of the diffraction grating is smaller than an irradiation region of the charged particle beam on the diffraction grating. Image data is obtained in a state where the irradiation region of the charged particle beam diffracted with the diffraction grating is within the irradiation region of the charged particle beam transmitted through the diffraction grating. Plural holograms obtained based on the image data are Fourier transformed and an intensity distribution image is displayed and stored.

公开(公告)号：US11551907B2

公开(公告)日：2023-01-10

申请号：US17263017

申请日：2019-07-26

Applicant: RIKEN ,  UNIVERSITY PUBLIC CORPORATION OSAKA

Inventor： Ken Harada ,  Keiko Shimada ,  Shigeo Mori ,  Atsuhiro Kotani

IPC: H01J37/26 ,  G01N23/201 ,  H01J37/09 ,  H01J37/10 ,  H01J37/147 ,  H01J37/20 ,  H01J37/22

Abstract: An observation apparatus and method that avoids drawbacks of a Lorentz method and observes a weak scatterer or a phase object with in-focus, high resolution, and no azimuth dependency, by a Foucault method observation using a hollow-cone illumination that orbits and illuminates an incident electron beam having a predetermined inclination angle, an electron wave is converged at a position (height) of an aperture plate downstream of a sample, and a bright field condition in which a direct transmitted electron wave of the sample passes through the aperture plate, a dark field condition in which the transmitted electron wave is shielded, and a Schlieren condition in which approximately half of the transmitted wave is shielded as a boundary condition of both of the above conditions are controlled, and a spatial resolution of the observation image is controlled by selecting multiple diameters and shapes of the opening of the aperture plate.

公开(公告)号：US10770264B2

公开(公告)日：2020-09-08

申请号：US16360812

申请日：2019-03-21

Applicant: RIKEN

Inventor： Yoh Iwasaki ,  Ken Harada ,  Keiko Shimada

IPC: H01J37/26 ,  H01J37/141 ,  H01J37/147

Abstract: An interference optical system unit includes at least one electromagnetic lens that forms an image of a charged particle beam, at least one charged particle beam biprism, and a support member for the electromagnetic lens and the charged particle beam biprism. The electromagnetic lens, the charged particle beam biprism, the support member, and a space to an image plane of the electromagnetic lens are integrally configured as one unit. The interference optical system unit is disposed to have an optical axis coaxialized with an optical axis of an imaging optical system of an upstream stage that is disposed on an upstream side of the unit in a flow direction of the charged particle beam. A focal length of the electromagnetic lens and a deflection angle of the charged particle beam given by the charged particle beam biprism are controlled to generate an interference fringe of the charged particle beam on the image plane of the electromagnetic lens.