Abstract: A method of determining a brightness (Br) of a charged particle beam (11) focused by a focusing lens (120) toward a sample (10) in a charged particle beam imaging device (100) is described. The method includes (a) taking one or more images (hf, 1 . . . N) of the sample with the charged particle beam imaging device; (b) retrieving one or more beam profiles (gf, 1 . . . N) of the charged particle beam from the one or more images; and (c) determining the brightness (Br) of the charged particle beam (11) based on at least the one or more beam profiles (gf, g1 . . . N), a probe current (Ip) of the charged particle beam, and a landing potential (LE) of the charged particle beam. Optionally, the brightness (Br) determined as above can be used for determining a size (Dvirt) of a source (105) of the charged particle beam (11). Further, a charged particle beam imaging device (100) configured for any of the methods described herein is provided.

Abstract: A magnetic multipole device for influencing a charged particle beam propagating along an optical axis is provided. The magnetic multipole device includes a first magnetic deflector for deflecting the charged particle beam in an x-direction with a plurality of first saddle coils; and a second magnetic deflector for deflecting the charged particle beam in a y-direction perpendicular to the x-direction with a plurality of second saddle coils. The first and second saddle coils are arranged around the optical axis in a 12-pole magnetic corrector structure with 12 poles provided at uniformly spaced angular intervals. The 12-pole magnetic corrector structure is configured to exert a beam correction field of a magnetic 12-pole corrector on the charged particle beam. Further provided are a charged particle beam apparatus with a magnetic multipole device and a method of influencing a charged particle beam propagating along an optical axis with a magnetic multipole device as described herein.

Abstract: It is provided a current measurement module 100 for measuring a current of a primary charged particle beam 123 of a charged particle beam device, the current measurement module 100 including a detection unit 160 configured for detecting secondary and/or backscattered charged particles 127 released on impingement of the primary charged particle beam 123 on a conductive surface 142 of a beam dump 140 of the charged particle beam device.

Abstract: A method of determining aberrations of a charged particle beam (11) focused by a focusing lens (120) toward a sample (10) in a charged particle beam system is described. The method includes: (a) taking one or more images of the sample at one or more defocus settings to provide one or more taken images (h1...N); (b) simulating one or more images of the sample taken at the one or more defocus settings based on a set of beam aberration coefficients (iC) and a focus image of the sample to provide one or more simulated images; (c) comparing the one or more taken images and the one or more simulated images for determining a magnitude (Ri) of a difference therebetween; and (d) varying the set of beam aberration coefficients (iC) to provide an updated set of beam aberration coefficients (i+1C) and repeating (b) and (c) using the updated set of beam aberration coefficients (i+1C) in an iterative process for minimizing said magnitude (Ri).

Abstract: A method of determining aberrations of a charged particle beam (11) focused by a focusing lens (120) with a given numerical aperture (NA) toward a sample (10) in a charged particle beam system is described. The method includes: (a.) simulating, based at least on the given numerical aperture (NA), one or more beam cross sections at one or more first defocus settings for each of two or more different values of a first beam aberration coefficient (C1) of a set of beam aberration coefficients (C1 . . . n), to provide a plurality of first simulated beam cross sections; (b.) extracting two or more values of a first aberration characteristic (˜C1) that is related to the first beam aberration coefficient (C1) from the plurality of first simulated beam cross sections; (c.) determining a first dependency between the first beam aberration coefficient (C1) and the first aberration characteristic (˜C1); (d.

Abstract: A method of determining a beam convergence of a charged particle beam (11) focused by a focusing lens (120) toward a sample (10) in a charged particle beam system (100) is provided. The method includes (a) taking one or more images of the sample when the sample is arranged at one or more defocus distances from a respective beam focus of the charged particle beam; (b) retrieving one or more beam cross sections from the one or more images; (c) determining one or more beam widths from the one or more beam cross sections; and (d) calculating at least one beam convergence value based on the one or more beam widths and the one or more defocus distances. Further, a charged particle beam system for imaging and/or inspecting a sample that is configured for any of the methods described herein is provided.

Abstract: It is provided a charged particle beam manipulation device for a plurality of charged particle beamlets, the charged particle beam manipulation device including a lens having a main optical axis, the lens including at least a first array of multipoles, each multipole of the first array of multipoles configured to compensate for a lens deflection force on a respective charged particle beamlet of the plurality of charged particle beamlets, the lens deflection force being a deflection force produced by the lens on the respective charged particle beamlet towards the main optical axis of the lens.

Abstract: An electron microscope (100) is described. The electron microscope comprises an electron source (110) for generating an electron beam, a condenser lens (130) for collimating the electron beam downstream of the electron source, and an objective lens (140) for focusing the electron beam onto a specimen (16). The electron source comprises a cold field emitter with an emission tip (112), an extractor electrode (114) for extracting the electron beam (105) from the cold field emitter for propagation along an optical axis (A), the extractor electrode having a first opening (115) configured as a first beam limiting aperture, a first cleaning arrangement (121) for cleaning the emission tip (112) by heating the emission tip, and a second cleaning arrangement (122) for cleaning the extractor electrode (114) by heating the extractor electrode. Further described is a method of operating such an electron microscope.

Abstract: A method of determining a beam convergence of a charged particle beam (11) focused by a focusing lens (120) toward a sample (10) in a charged particle beam system (100) is provided. The method includes (a) taking one or more images of the sample when the sample is arranged at one or more defocus distances from a respective beam focus of the charged particle beam; (b) retrieving one or more beam cross sections from the one or more images; (c) determining one or more beam widths from the one or more beam cross sections; and (d) calculating at least one beam convergence value based on the one or more beam widths and the one or more defocus distances. Further, a charged particle beam system for imaging and/or inspecting a sample that is configured for any of the methods described herein is provided.

Abstract: A method of determining aberrations of a charged particle beam (11) focused by a focusing lens (120) toward a sample (10) in a charged particle beam system is described. The method includes: (a) taking one or more images of the sample at one or more defocus settings to provide one or more taken images (h1...N); (b) simulating one or more images of the sample taken at the one or more defocus settings based on a set of beam aberration coefficients (iC) and a focus image of the sample to provide one or more simulated images; (c) comparing the one or more taken images and the one or more simulated images for determining a magnitude (Ri) of a difference therebetween; and (d) varying the set of beam aberration coefficients (iC) to provide an updated set of beam aberration coefficients (i+1C) and repeating (b) and (c) using the updated set of beam aberration coefficients (i+1C) in an iterative process for minimizing said magnitude (Ri).

Abstract: Provided is an aberration corrector having a plurality of magnetic poles including a first magnetic pole and further magnetic poles, a ring that magnetically connects the plurality of magnetic poles with one another, the ring having a constant spacing to at least the first magnetic pole, a plurality of magnetic field modulators including a first magnetic field modulator and further magnetic field modulators, and a plurality of guides including a first guide and further guides; wherein the first magnetic field modulator includes a soft magnetic material, wherein the first magnetic field modulator is disposed in a first position, the first position being one of the following: adjacent to a first air gap separating the first magnetic pole and the ring, or at an inner ring surface or radially outward of the inner ring surface along an axis of the first magnetic pole, and wherein the first guide constrains the first magnetic field modulator to positions along a first axis substantially parallel to or coincident wi

Abstract: A method of influencing a charged particle beam (11) propagating along an optical axis (A) is described. The method includes: guiding the charged particle beam (11) through at least one opening (102) of a multipole device (100, 200) that comprises a first multipole (110, 210) with four or more first electrodes (111, 211) and a second multipole (120, 220) with four or more second electrodes (121, 221) arranged in the same sectional plane, the first electrodes and the second electrodes being arranged alternately around the at least one opening (102); and at least one of exciting the first multipole to provide a first field distribution for influencing the charged particle beam in a first manner, and exciting the second multipole to provide a second field distribution for influencing the charged particle beam in a second manner.

Abstract: A charged particle beam apparatus for inspecting a specimen with a plurality of beamlets is described. The charged particle beam apparatus includes a charged particle beam emitter (105) for generating a charged particle beam (11) propagating along an optical axis (A) and a multi-beamlet generation- and correction-assembly (120), including a first multi-aperture electrode (121) with a first plurality of apertures for creating the plurality of beamlets from the charged particle beam, at least one second multi-aperture electrode (122) with a second plurality of apertures of varying diameters for the plurality of beamlets for providing a field curvature correction, and a plurality of multipoles (123) for individually influencing each of the plurality of beamlets, wherein the multi-beamlet generation- and correction-assembly (120) is configured to focus the plurality of beamlets to provide a plurality of intermediate beamlet crossovers.

Abstract: A charged particle beam apparatus (100) is described. The charged particle beam apparatus includes a first vacuum region (121) in which a charged particle beam emitter (105) for emitting a charged particle beam (102) along an optical axis (A) is arranged, a second vacuum region (122) downstream of the first vacuum region and separated from the first vacuum region by a first gas separation wall (132) with a first differential pumping aperture (131), wherein the first differential pumping aperture (131) is configured as a first beam limiting aperture for the charged particle beam (102); and a third vacuum region (123) downstream of the second vacuum region and separated from the second vacuum region by a second gas separation wall (134) with a second differential pumping aperture (133), wherein the second differential pumping aperture (133) is configured as a second beam limiting aperture for the charged particle beam (102).

Abstract: A method of operating a charged particle beam device is disclosed, including focusing a charged particle beam onto a sample with an objective lens assembly; passing a reflected light beam through a bore of the objective lens assembly to an interferometer; and interferometrically determining a z-position of the sample with the interferometer. A charged particle beam device is disclosed, including a charged particle beam generator which has a charged particle source. A charged particle path for the charged particle beam extends through a bore of an objective lens assembly toward a sample stage. An interferometer is arranged to receive a reflected light beam which passes through the bore of the objective lens assembly.

Abstract: A charged particle beam device for imaging and/or inspecting a sample is described. The charged particle beam device includes a beam emitter for emitting a primary charged particle beam; a retarding field device for retarding the primary beam before impinging on the sample, the retarding field device including an objective lens and a proxy electrode; and a first detector for off-axial backscattered particles between the proxy electrode and the objective lens. The charged particle beam device is adapted for guiding the primary beam along an optical axis to the sample for releasing signal particles. The proxy electrode includes one opening allowing a passage of the primary charged particle beam and of the signal particles, wherein the one opening is sized to allow a passage of charged particles backscattered from the sample at angles from 0° to 20° or above relative to the optical axis. Further, a method for imaging and/or inspecting a sample with a charged particle beam device is described.

Abstract: A charged particle gun for a charged particle beam device is described. The charged particle gun includes a gun housing; an emitter provided in the gun housing, the emitter being configured to emit a charged particle beam along an axis; an emitter power supply connected to the emitter; a trapping electrode provided in the gun housing, the trapping electrode at least partially surrounding the axis; a trapping power supply connected to the trapping electrode; and a shielding element shielding an electrostatic field of the trapping electrode from the axis during operation of the gun housing.

Abstract: A charged particle beam device for imaging and/or inspecting a sample is described.

Abstract: An electrode arrangement for acting on a charged particle beam in a charged particle beam apparatus is described. The electrode arrangement includes a first electrode with a first opening for the charged particle beam; a first spacer element positioned in a first recess provided in the first electrode on a first electrode side for aligning the first electrode relative to a second electrode, the first spacer element having a first blind hole; a first conductive shield provided in the first blind hole; and a contact assembly protruding from the first electrode into the first blind hole for ensuring an electrical contact between the first electrode and the first conductive shield. Further, a contact assembly for such an electrode arrangement, a charged particle beam device with such an electrode arrangement, as well as a method of reducing an electrical field strength in an electrode arrangement are described.

Abstract: A beam blanking device for a multi-beamlet charged particle beam apparatus is provided. The beam blanking device includes a first blanking unit, a second blanking unit and a third blanking unit. The first blanking unit includes a first blanking electrode and a first aperture. The second blanking unit includes a second blanking electrode and a second aperture. The third blanking unit includes a third blanking electrode and a third aperture. The beam blanking device includes a common electrode forming a first counter electrode for the first blanking electrode, a second counter electrode for the second blanking electrode and a third counter electrode for the third blanking electrode. The first blanking unit, the second blanking unit and the third blanking unit are arranged in a planar array and define a plane of the planar array.