Abstract: An electron optical module for providing an off-axial electron beam with a tunable coma, according to the present disclosure includes a structure positioned downstream of an electron source and an electron lens assembly positioned between the structure and the electron source. The structure generates a decelerating electric field, and is positioned to prevent the passage of electrons along the optical axis of the electron lens assembly. The electron optical module further includes a micro-lens that is not positioned on the optical axis of the electron lens assembly and is configured to apply a lensing effect to an off-axial election beam. Aberrations applied to the off-axial electron beam by the micro-lens and the electron lens assembly combine so that a coma of the off-axial beam has a desired value in a downstream plane.

Abstract: Systems and methods for reducing the buildup of charge during the investigation of samples using charged particle beams, according to the present disclosure include irradiating a first portion of a sample during a first time period, wherein the irradiating the first portion of the sample causes a gradual accumulation of net charge in the first portion of the sample, generating imaging data based on emissions resultant from irradiating the first portion of the sample, and then irradiating a second portion of a sample holder for a second time period. The methods may further includes iteratively repeating the irradiation of the first portion and the second portion during imaging of the sample region. When more than one region of interest on the sample is to be investigated, the method may also include continuing to image additional portions of the sample by iteratively irradiating a region of interest on the sample and a corresponding portion of the sample holder.

Abstract: Methods for using electron diffraction holography to investigate a sample, according to the present disclosure include the initial steps of emitting a plurality of electrons toward the sample, forming the plurality of electrons into a first electron beam and a second electron beam, and modifying the focal properties of at least one of the two beams such that the two beams have different focal planes. Once the two beams have different focal planes, the methods include focusing the first electron beam such that it has a focal plane at or near the sample, and focusing the second electron beam so that it is incident on the sample, and has a focal plane in the diffraction plane. An interference pattern of the first electron beam and the diffracted second electron beam is then detected in the diffraction plane, and then used to generate a diffraction holograph.

Abstract: An energy spectrometer with dynamic focus for a transmission electron microscope (TEM) is disclosed herein. An example energy spectrometer and TEM at least includes a charged particle column including a projection system arranged after a sample plane, the projection system is operated in a first configuration; an energy spectrometer coupled to the charged particle column to acquire one or more energy loss spectra. The energy spectrometer including a dispersive element, a bias tube, optics for magnifying the energy loss spectrum and for correcting aberrations, and a detector arranged conjugate to a spectrum plane of the energy spectrometer, wherein the energy spectrometer further includes an optical element electrically biased to refocus at least a portion of a spectrum onto the detector, and wherein the value of the electrical bias is at least partially based on the first configuration of the charged particle column.

Abstract: Systems for reducing the generation of thermal magnetic field noise in optical elements of microscope systems, are disclosed. Example microscopy optical elements having reduced Johnson noise generation according to the present disclosure comprises an inner core composed of an electrically isolating material, and an outer coating composed of an electrically conductive material. The product of the thickness of the outer coating and the electrical conductivity is less than 0.01??1. The outer coating causes a reduction in Johnson noise generated by the optical element of greater than 2×, 3×, or an order of magnitude or greater. In a specific example embodiment, the optical element is a corrector system having reduced Johnson noise generation. Such a corrector system comprises an outer magnetic multipole, and an inner electrostatic multipole. The inner electrostatic multipole comprises an inner core composed of an electrically isolating material and an outer coating composed of an electrically conductive material.

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: Methods for using electron diffraction holography to investigate a sample, according to the present disclosure include the initial steps of emitting a plurality of electrons toward the sample, forming the plurality of electrons into a first electron beam and a second electron beam, and modifying the focal properties of at least one of the two beams such that the two beams have different focal planes. Once the two beams have different focal planes, the methods include focusing the first electron beam such that it has a focal plane at or near the sample, and focusing the second electron beam so that it is incident on the sample, and has a focal plane in the diffraction plane. An interference pattern of the first electron beam and the diffracted second electron beam is then detected in the diffraction plane, and then used to generate a diffraction holograph.

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: An adjustable magnetic field free objective lens for a charged particle microscope is disclosed herein. An example charged particle microscope at least includes first and second optical elements arranged on opposing sides of a sample plane, a third optical element arranged around the sample plane, and a controller coupled to control the first, second and third optical elements. The controller coupled to excite the first and second optical elements to generate first and second magnetic lenses, the first and second magnetic lenses formed on opposing sides of the sample plane and oriented in the same direction, and excite the third optical element to generate a third magnetic lens at the sample plane that is oriented in an opposite direction, where a ratio of the excitation of the third optical element to the excitation of the first and second optical elements adjusts a magnetic field at the sample plane.

Abstract: Systems for reducing the generation of thermal magnetic field noise in optical elements of microscope systems, are disclosed. Example microscopy optical elements having reduced Johnson noise generation according to the present disclosure comprises an inner core composed of an electrically isolating material, and an outer coating composed of an electrically conductive material. The product of the thickness of the outer coating and the electrical conductivity is less than 0.01??1. The outer coating causes a reduction in Johnson noise generated by the optical element of greater than 2×, 3×, or an order of magnitude or greater. In a specific example embodiment, the optical element is a corrector system having reduced Johnson noise generation. Such a corrector system comprises an outer magnetic multipole, and an inner electrostatic multipole. The inner electrostatic multipole comprises an inner core composed of an electrically isolating material and an outer coating composed of an electrically conductive material.

Abstract: Methods for using a single electron microscope system for investigating a sample with TEM and STEM techniques include the steps of emitting electrons toward the sample, forming the electrons into a two beams, and then modifying the focal properties of at least one of the two beams such that they 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 that is focused at the sample, and the second electron beam is focused so that it acts as a TEM beam that is parallel beam when incident on the sample. Emissions resultant from the STEM beam and the TEM beam being incident on the sample can then be detected by a single detector or detector array and used to generate a TEM image and a STEM image.

Abstract: Systems for reducing the generation of thermal magnetic field noise in optical elements of microscope systems, are disclosed. Example microscopy optical elements having reduced Johnson noise generation according to the present disclosure comprises an inner core composed of an electrically isolating material, and an outer coating composed of an electrically conductive material. The product of the thickness of the outer coating and the electrical conductivity is less than 0.01??1. The outer coating causes a reduction in Johnson noise generated by the optical element of greater than 2×, 3×, or an order of magnitude or greater. In a specific example embodiment, the optical element is a corrector system having reduced Johnson noise generation. Such a corrector system comprises an outer magnetic multipole, and an inner electrostatic multipole. The inner electrostatic multipole comprises an inner core composed of an electrically isolating material and an outer coating composed of an electrically conductive material.

Abstract: An adjustable magnetic field free objective lens for a charged particle microscope is disclosed herein. An example charged particle microscope at least includes first and second optical elements arranged on opposing sides of a sample plane, a third optical element arranged around the sample plane, and a controller coupled to control the first, second and third optical elements. The controller coupled to excite the first and second optical elements to generate first and second magnetic lenses, the first and second magnetic lenses formed on opposing sides of the sample plane and oriented in the same direction, and excite the third optical element to generate a third magnetic lens at the sample plane that is oriented in an opposite direction, where a ratio of the excitation of the third optical element to the excitation of the first and second optical elements adjusts a magnetic field at the sample plane.

Abstract: Correctors for correcting two-fold, fifth-order parasitic aberrations in charged particle systems according to the present disclosure include a first corrective component that generates a first quadrupole field when a first excitation is applied to the first corrective component, and a second corrective component that generates a second quadrupole field when a second excitation is applied to the second corrective component. Correctors according to the present disclosure also include a quadrupole positioned between the second corrective component and the sample when used in the charged particle microscope system that generates a third quadrupole field. The third quadrupole field, in combination with at least the first quadrupole field and the second quadrupole field, corrects the fifth-order, two-fold aberrations when the charged particle microscope is in use.

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 for using electron diffraction holography to investigate a sample, according to the present disclosure include the initial steps of emitting a plurality of electrons toward the sample, forming the plurality of electrons into a first electron beam and a second electron beam, and modifying the focal properties of at least one of the two beams such that the two beams have different focal planes. Once the two beams have different focal planes, the methods include focusing the first electron beam such that it has a focal plane at or near the sample, and focusing the second electron beam so that it is incident on the sample, and has a focal plane in the diffraction plane. An interference pattern of the first electron beam and the diffracted second electron beam is then detected in the diffraction plane, and then used to generate a diffraction holograph.

Abstract: Methods and systems for investigating a sample using a dual beam bifocal charged particle microscope, according to the present disclosure include emitting a plurality of charged particles toward the sample, forming the plurality of charged particles into a first charged particle beam and a second charged particle beam, and modifying the focal properties of at least one of the first charged particle beam and the second charged particle beam. The focal properties of at least one of the first charged particle beam and the second charged particle beam is modified such that the corresponding focal planes of the first charged particle beam and the second charged particle beam are different.

Abstract: Methods for using a single electron microscope system for investigating a sample with TEM and STEM techniques include the steps of emitting electrons toward the sample, forming the electrons into a two beams, and then modifying the focal properties of at least one of the two beams such that they 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 that is focused at the sample, and the second electron beam is focused so that it acts as a TEM beam that is parallel beam when incident on the sample. Emissions resultant from the STEM beam and the TEM beam being incident on the sample can then be detected by a single detector or detector array and used to generate a TEM image and a STEM image.