Jeol Ltd.

The University of Tokyo

Yuji Kohno

Akiho Nakamura

Hidetaka Sawada

Naoya Shibata

Tatsuo Naruse

Norikazu Arima

Kazunori Somehara

There is provided an image processing method capable of generating an image representative of a magnetic field distribution. The method starts with acquiring phase images providing visualization of electromagnetic fields respectively in a plurality of columns. Then, each of the electromagnetic fields in the columns within the phase images is separated into magnetic field and electric field components. An image representative of a magnetic field distribution is created based on the separated magnetic field components. The step of separating each electromagnetic field includes separating the electromagnetic field in a first one of the columns into magnetic field and electric field components based on the electromagnetic field in a second one of the columns, the latter electromagnetic field having an electric field component oriented in the same direction as that in the first column.

Method and apparatus for image processing

A method of acquiring a dark-field image for a scanning transmission electron microscope is provided. The scanning transmission electron microscope includes a dark-field detector having an annular detection region which is capable of detecting electrons scattered at a specimen in a predetermined angular range, an objective lens, and an imaging lens group disposed at a stage following the objective lens. The method includes reducing an influence of a geometrical aberration on the electrons scattered in the predetermined angular range by shifting a focus of the imaging lens group from a diffraction plane of the objective lens.

Method of acquiring dark-field image

An image acquisition method is provided for use in an electron microscope for scanning a sample by an electron probe and acquiring a scanned image. The method includes the steps of: raster scanning a region of the sample under observation with the electron probe and obtaining a first scanned image; raster scanning the region under observation with the electron probe and obtaining a second scanned image; and superimposing the first and second scanned images over each other. In the step of obtaining the first scanned image, each one of scan lines is drawn with the electron probe in a first direction and then moved in a second direction perpendicular to the first direction. In the step of obtaining the second scanned image, each one of the scan lines is drawn with the electron probe in the first direction and then moved in a third direction opposite to the second direction.

Image acquisition method and electron microscope

There is provided a deflector that produces only a weak resulting combined hexapole field. The deflector () has first to sixth coils (-). The first to third coils (-) are equal in direction of energization. The fourth to sixth coils (-) are equal in direction of energization. The first coil () and fourth coil () are opposite in direction of energization. The first, third, fourth, and sixth coils () are equal in electromotive force. The second coil () is equal in electromotive force to the fifth coil () and twice the electromotive force of the first coil ().

Deflector and charged particle beam system

A method of controlling a transmission electron microscope includes: causing a first magnetic field lens to generate a first magnetic field and causing a second magnetic field lens to generate a second magnetic field; causing the magnetic field applying unit to generate a magnetic field of a direction along an optical axis on a specimen mounting surface; and changing excitations of the first excitation coil and the second excitation coil to correct a deviation of a focal length of an objective lens due to the magnetic field generated by the magnetic field applying unit.

Method of controlling transmission electron microscope and transmission electron microscope

A cold cathode field-emission electron gun includes: an emitter; an extraction electrode which extracts electrons from the emitter; and a biased electrode which is disposed closer to the emitter than the extraction electrode. A voltage applied to the biased electrode is variable.

Cold cathode field-emission electron gun, adjustment method for cold cathode field-emission electron gun, sharpening method for emitter, and electron microscope

There is provided a method of aberration measurement capable of reducing the effects of image drift. The novel method of aberration measurement is for use in an electron microscope. The method comprises the steps of: acquiring a first image that is a TEM (transmission electron microscope) image of a sample; scanning the illumination angle of an electron beam impinging on the sample and acquiring a second image by multiple exposure of a plurality of TEM images generated at different illumination angles; and calculating aberrations from the first and second images.

Method of aberration measurement and electron microscope

An aberration measurement method for an objective lens in an electron microscope including an objective lens which focuses an electron beam that illuminates a specimen, and a detector which detects an electron beam having passed through the specimen, includes: introducing a coma aberration to the objective lens; measuring an aberration of the objective lens before introducing the coma aberration to the objective lens; measuring an aberration of the objective lens after introducing the coma aberration to the objective lens; and obtaining a position of an optical axis of the objective lens on a detector plane of the detector based on measurement results of the aberration of the objective lens before and after introducing the coma aberration.

Aberration measurement method and electron microscope

Provided is a measurement method for measuring, in an electron microscope including a segmented detector having a detection plane segmented into a plurality of detection regions, a direction of each of the plurality of detection regions in a scanning transmission electron microscope (STEM) image, the measurement method including: shifting an electron beam EB incident on a sample S under a state where the detection plane is conjugate to a plane shifted from a diffraction plane to shift the electron beam EB on the detection plane, and measuring a shift direction of the electron beam EB on the detection plane with the segmented detector; and obtaining the direction of each of the plurality of detection regions in the STEM image from the shift direction.

Measurement method and electron microscope

There is provided an objective lens capable of reducing the effects of magnetic fields on a sample. The objective lens includes a first lens and a second lens. The lenses are arranged so that the component of the magnetic field of the first lens lying along the optical axis and the component of the magnetic field of the second lens lying along the optical axis cancel out each other at a sample placement surface. The first and second lenses each include an inner polepiece and an outer polepiece. The inner polepieces have front end portions, respectively. The outer polepieces have front end portions, respectively, which jut out toward the optical axis. The distances of the front end portions of the outer polepieces, respectively, from the sample placement surface are less than the distances of the front end portions of the inner polepieces, respectively, from the sample placement surface.

Objective lens and transmission electron microscope

There is provided an electron microscope capable of measuring aberration with high accuracy. The electron microscope () comprises: an electron beam source () for producing an electron beam (EB); an illumination lens system () for focusing the electron beam (EB) onto a sample (S); a scanner () for scanning the focused electron beam (EB) over the sample (S); an aperture stop () having a plurality of detection angle-limiting holes () for extracting rays of the electron beam (EB) having mutually different detection angles from the electron beam (EB) transmitted through the sample (S); and a detector () for detecting the rays of the electron beam (EB) passed through the aperture stop ().

Electron microscope and method of aberration measurement

An electron microscope is provided which can measure, with high sensitivity and high positional resolution, an amount of deflection of an electron beam occurring when it is transmitted through a sample. The electron microscope () is adapted to measure the amount of deflection of the electron beam (EB) when it is transmitted through the sample (S), and has an electron beam source () producing the electron beam (EB), an illumination lens system for focusing the electron beam (EB) onto the sample (S), an aperture () having an electron beam blocking portion () for providing a shield between a central portion (EB) and an outer peripheral portion (EB) of the cross section of the beam (EB) impinging on the sample (S), and a segmented detector () having a detection surface () for detecting the electron beam (EB) transmitted through the sample (S). The detection surface () is divided into a plurality of detector segments (D-D).

Electron microscope and measurement method

An electron microscope capable of measuring aberrations accurately is provided. The microscope is adapted to obtain scanning transmission electron (STEM) images by detecting electrons transmitted through a sample (S). The microscope () includes a segmented detector () having a detection surface () for detecting the electrons transmitted through the sample (S). The detection surface () is divided into detector segments (D-D) for detecting the electrons transmitted through the sample (S). The microscope () further includes an aperture plate () for limiting the active areas of the detector segments (D-D) on which the electrons impinge.

Electron microscope and method of measuring aberrations

A measurement method capable of easily measuring the directions of detector segments of a segmented detector relative to a scanning transmission electron microscope (STEM) image is provided. The measurement method is for use in an electron microscope equipped with the segmented detector having a detection surface divided into the detector segments. The measurement method is used to measure the directions of the detector segments relative to the STEM image. The method involves defocusing the STEM image to thereby cause a deviation of the STEM image and measuring the directions of the detector segments relative to the STEM image from the direction of the deviation of the STEM image (step S).

A multipole lens is provided which is for use in electron microscopy and which is simple in structure but capable of producing X- and Y-components of a quadrupole field and X- and Y-components of an octopole field. The multipole lens () comprises: first through twelfth polar elements (-to-); first through sixteenth coils (-to-); a first power supply (-) for supplying currents to the coils (----); a second power supply (-) for supplying currents to the coils (----); a third power supply (-) for supplying excitation currents to the coils (----); and a fourth power supply (-) for supplying excitation currents to the coils (----). The coils (--------) produce magnetic fields in a first direction. The coils (--------) produce magnetic fields in a direction opposite to the first direction.

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Tokyo, Japan

Yuji Kohno