Abstract: In a transmission electron microscope, an intermediate lens assembly receives a beam of electrons after leaving a primary lens and forms an image of a sample in a sample holder. The intermediate lens assembly comprises a first lens, a second lens, a first port in a first port plane and a second port in a second port plane. The first port and the second port receive a wave front manipulating device for manipulating the wave front of the beam. In a first mode, a controller controls the first and second lenses to direct the diffraction pattern into a second diffraction plane wherein the second diffraction plane is coincident with the first port plane. In a second mode, the controller controls the first and second lenses to direct the diffraction pattern into a third diffraction plane wherein the third diffraction plane is coincident with the second port plane.

Abstract: Systems, methods, and components of charged particle microscopes affording improved contrast in dose sensitive samples are described. A pole piece for an electron microscope can include a body, being substantially concentric with a central axis. The body can define an upper surface, substantially normal to the central axis, a lower surface, substantially normal to the central axis, a central aperture formed in the body from the upper surface to the lower surface. The central aperture can be substantially rotationally symmetrical about the central axis. The body can define a lateral surface, inclined relative to the central axis and tapering toward the upper surface and a plurality of lateral apertures formed in the body from the lateral surface to the central aperture. The plurality of lateral apertures can be arrayed substantially symmetrically about the central axis.

Abstract: Method and system for generating a diffraction image comprises acquiring multiple frames from a direct-detection detector responsive to irradiating a sample with an electron beam. Multiple diffraction peaks in the multiple frames are identified. A first dose rate of at least one diffraction peak in the identified diffraction peaks is estimated in the counting mode. If the first dose rate is not greater than a threshold dose rate, a diffraction image including the diffraction peak is generated by counting electron detection events. Values of pixels belonging to the diffraction peak are determined with a first set of counting parameter values corresponding to a first coincidence area. Values of pixels not belonging to any of the multiple diffraction peaks are determined using a second, set of counting parameter values corresponding to a second, different, coincidence area.

Abstract: Molecular structure of a crystal may be solved based on at least two diffraction tilt series acquired from a sample. The two diffraction tilt series include multiple diffraction patterns of at least one crystal of the sample acquired at different electron doses. In some examples, the two diffraction tilt series are acquired at different magnifications.

Abstract: Crystallographic information of crystalline sample can be determined from one or more three-dimensional diffraction pattern datasets generated based on diffraction patterns collected from multiple crystals. The crystals for diffraction pattern acquisition may be selected based on a sample image. At a location of each selected crystal, multiple diffraction patterns of the crystal are acquired at different angles of incidence by tilting the electron beam, wherein the sample is not rotated while the electron beam is directed at the selected crystal.

Abstract: Method and system for generating a diffraction image comprises acquiring multiple frames from a direct-detection detector responsive to irradiating a sample with an electron beam. Multiple diffraction peaks in the multiple frames are identified. A first dose rate of at least one diffraction peak in the identified diffraction peaks is estimated in the counting mode. If the first dose rate is not greater than a threshold dose rate, a diffraction image including the diffraction peak is generated by counting electron detection events. Values of pixels belonging to the diffraction peak are determined with a first set of counting parameter values corresponding to a first coincidence area. Values of pixels not belonging to any of the multiple diffraction peaks are determined using a second, set of counting parameter values corresponding to a second, different, coincidence area.

Abstract: Diffraction patterns of a sample at various tilt angles are acquired by irradiating a region of interest using a first charged particle beam. Sample images are acquired by irradiating the region of interest using a second charged particle beam. The first and second charged particle beams are formed by splitting charged particles generated by a charged particle source.

Abstract: Methods for using a dual beam microscope system to simultaneously process a sample and image the processed portions of the sample, according to the present disclosure include the initial steps of emitting a plurality of electrons toward the sample, splitting the plurality of electrons into two electron beams, and then modifying the focal properties of at least one of the electron beams such that the two electron beams have different focal planes. Once the two beams have different focal planes, the first electron beam is focused such that it acts as a STEM beam. The STEM beam is then used to process a region of the sample to induce a physical change (e.g., perform milling, deposition, charge adjustment, phase change, etc.).

Abstract: Methods for using a dual beam microscope system to simultaneously process a sample and image the processed portions of the sample, according to the present disclosure include the initial steps of emitting a plurality of electrons toward the sample, splitting the plurality of electrons into two electron beams, and then modifying the focal properties of at least one of the electron beams such that the two electron beams have different focal planes. Once the two beams have different focal planes, the first electron beam is focused such that it acts as a STEM beam. The STEM beam is then used to process a region of the sample to induce a physical change (e.g., perform milling, deposition, charge adjustment, phase change, etc.). The second electron beam is focused to act as a TEM beam to perform imaging of the region of the sample being processed.

Abstract: Diffraction patterns of a sample at various tilt angles are acquired by irradiating a region of interest using a first charged particle beam. Sample images are acquired by irradiating the region of interest using a second charged particle beam. The first and second charged particle beams are formed by splitting charged particles generated by a charged particle source.

Abstract: Methods and systems for implementing laser-based phase plate image contrast enhancement are disclosed herein. An example method at least includes forming at least one optical peak in a diffraction plane of an electron microscope, and directing an electron beam through the at least one optical peak at a first location, where the first location determines an amount of phase manipulation the optical peak imparts to an electron of the electron beam.

Abstract: Techniques of using a Transmission Charged Particle Microscope for diffraction pattern detection are disclosed. An example method including irradiating at least a portion of a specimen with a charged particle beam, using an imaging system to collect charged particles that traverse the specimen during said irradiation, and to direct them onto a detector configured to operate in a particle counting mode, using said detector to record a diffraction pattern of said irradiated portion of the specimen, recording said diffraction pattern iteratively in a series of successive detection frames, and during recording of each frame, using a scanning assembly for causing relative motion of said diffraction pattern and said detector, so as to cause each local intensity maximum in said pattern to trace out a locus on said detector.

Abstract: Molecular structure may be determined based on structure factors solved from the diffraction pattern and the electron microscopy image of the sample. In particular, the amplitudes of the structure factors may be determined based on intensities of diffraction peaks in the multiple diffraction patterns. The phases of the structure factors may be determined based on electron microscopy images and the intensities of the diffraction peaks.

Abstract: Molecular structure may be determined based on structure factors solved from the diffraction pattern and the electron microscopy image of the sample. In particular, the amplitudes of the structure factors may be determined based on intensities of diffraction peaks in the multiple diffraction patterns. The phases of the structure factors may be determined based on electron microscopy images and the intensities of the diffraction peaks.

Abstract: Methods and systems for implementing laser-based phase plate image contrast enhancement are disclosed herein. An example method at least includes forming at least one optical peak in a diffraction plane of an electron microscope, and directing an electron beam through the at least one optical peak at a first location, where the first location determines an amount of phase manipulation the optical peak imparts to an electron of the electron beam.

Abstract: Techniques of using a Transmission Charged Particle Microscope for diffraction pattern detection are disclosed. An example method including irradiating at least a portion of a specimen with a charged particle beam, using an imaging system to collect charged particles that traverse the specimen during said irradiation, and to direct them onto a detector configured to operate in a particle counting mode, using said detector to record a diffraction pattern of said irradiated portion of the specimen, recording said diffraction pattern iteratively in a series of successive detection frames, and during recording of each frame, using a scanning assembly for causing relative motion of said diffraction pattern and said detector, so as to cause each local intensity maximum in said pattern to trace out a locus on said detector.

Abstract: An x-ray source for computer tomography uses several sub-sources. An electron beam impacts the several sub-sources to achieve a high x-ray flux with high resolution. The several sub-sources produce a composite image, which is deconvolved to disentangle the composite image and render a useful image. The configuration of the several sub-sources can be optimized for a given specimen structure.

Abstract: Techniques of using a Transmission Charged Particle Microscope for diffraction pattern detection are disclosed. An example method including irradiating at least a portion of a specimen with a charged particle beam, using an imaging system to collect charged particles that traverse the specimen during said irradiation, and to direct them onto a detector configured to operate in a particle counting mode, using said detector to record a diffraction pattern of said irradiated portion of the specimen, recording said diffraction pattern iteratively in a series of successive detection frames, and during recording of each frame, using a scanning assembly for causing relative motion of said diffraction pattern and said detector, so as to cause each local intensity maximum in said pattern to trace out a locus on said detector.

Abstract: A method of investigating a specimen using X-ray tomography, comprising (a) mounting the specimen to a specimen holder, (b) irradiating the specimen with a beam of X-rays along a first line of sight through the specimen, and (c) detecting a flux of X-rays transmitted through the specimen and forming a first image. Then (d) repeating the steps (b) and (c) for a series of different lines of sight through the specimen, thereby producing a corresponding series of images.

Abstract: A method of investigating a specimen using X-ray tomography, comprising (a) mounting the specimen to a specimen holder, (b) irradiating the specimen with a beam of X-rays along a first line of sight through the specimen, and (c) detecting a flux of X-rays transmitted through the specimen and forming a first image. Then (d) repeating the steps (b) and (c) for a series of different lines of sight through the specimen, thereby producing a corresponding series of images.