Systems and methods for observing a sample in a multi-beam apparatus are disclosed. A charged particle optical system may include a deflector configured to form a virtual image of a charged particle source and a transfer lens configured to form a real image of the charged particle source on an image plane. The image plane may be formed at least near a beam separator that is configured to separate primary charged particles generated by the source and secondary charged particles generated by interaction of the primary charged particles with a sample. The image plane may be formed at a deflection plane of the beam separator. The multi-beam apparatus may include a charged-particle dispersion compensator to compensate dispersion of the beam separator. The image plane may be formed closer to the transfer lens than the beam separator, between the transfer lens and the charged-particle dispersion compensator.

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.

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.

Systems and methods for observing a sample in a multi-beam apparatus are disclosed. A charged particle optical system may include a deflector configured to form a virtual image of a charged particle source and a transfer lens configured to form a real image of the charged particle source on an image plane. The image plane may be formed at least near a beam separator that is configured to separate primary charged particles generated by the source and secondary charged particles generated by interaction of the primary charged particles with a sample. The image plane may be formed at a deflection plane of the beam separator. The multi-beam apparatus may include a charged-particle dispersion compensator to compensate dispersion of the beam separator. The image plane may be formed closer to the transfer lens than the beam separator, between the transfer lens and the charged-particle dispersion compensator.

The invention provides a multi-pole deflector for a charged particle beam, and a charged particle beam imaging apparatus. The deflector includes a plurality of poles, including at least two pairs of poles, each pole in each pair of poles including a main body constructed in the form of a circular arc-shaped section and a protrusion projecting from an radial inner side of the main body. respective two main bodies of each pair of poles are arranged concentrically and diametrically opposite, and the at least two pairs of poles at least partially encompass and delimit a through-hole thereamong, which opens axially and is configured to receive and to pass therethrough the charged particle beam; and the at least two pairs of poles cooperate to generate respective secondary deflection fields distributed within the through-hole and across an internal space defined within the through-hole, respectively, and the secondary deflection fields are synthesized by combination of vectors into a resultant deflection field of the deflector which is distributed within and across the through-hole and is configured to deflect the charged particle beam passing therethrough.

An electron-beam device includes a laser and a photocathode film. The photocathode film has a front side and a back side and emits a plurality of electron beamlets when illuminated from the back side using the laser. The electron-beam device also includes electrodes to extract the plurality of electron beamlets from the front side of the photocathode film and to control shapes of the plurality of electron beamlets.

The present disclosure aims at proposing a multi-beam irradiation device capable of correcting off-axis aberrations. In order to achieve the above object, a beam irradiation device is proposed, which includes a beam source which emits a plurality of beams; an objective lens (17) which focuses a beam on a sample; a first lens (16) which is arranged such that a lens main surface is positioned at an object point of the objective lens and deflects a plurality of incident beams toward an intersection point of a lens main surface of the objective lens and an optical axis; a second lens (15) which is arranged closer to a beam source side than the first lens and focuses the plurality of beams on a lens main surface of the first lens; and a third lens (14) which is arranged closer to the beam source side than the second lens and deflects the plurality of beams toward an intersection point of a lens main surface of the second lens and the optical axis.

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.

A multi-beam particle microscope includes a multi-beam particle source, an objective lens, a detector arrangement, and a multi-aperture plate with a multiplicity of openings. The multi-aperture plate is between the objective lens and the object plane. The multi-aperture plate includes a multiplicity of converters which convert backscattered electrons which are generated by primary particle beams at an object into electrons with a lower energy, which provide electrons that form electron beams detected by the detector arrangement.

An object of the present disclosure is to propose a charged particle beam device capable of appropriately evaluating and setting a beam aperture angle. As one aspect for achieving the above-described object, provided is a charged particle beam device which includes a plurality of lenses and controls the plurality of lenses so as to set a focus at a predetermined height of a sample and to adjust the beam aperture angle. The charged particle beam device generates a first signal waveform based on a detection signal obtained by scanning with the beam in a state where the focus is set at a first height that is a bottom portion of a pattern formed on the sample, calculates a feature amount of a signal waveform on a bottom edge of the pattern based on the first signal waveform, and calculates the beam aperture angle based on the calculated feature amount.