A method of operating a multi-beam particle beam system includes: generating a multiplicity of particle beams such that they each pass through multipole elements that are either intact or defective; focusing the particle beams in a predetermined plane; determining excitations for the deflection elements of the multipole elements; exciting the deflection elements of the multipole elements that are intact with the determined excitations; modifying the determined excitations for the deflection elements of the multipole elements that are defective; and exciting the deflection elements of the defective multipole elements with the modified excitations. Modifying the determined excitations includes adding corrective excitations to the determined excitations. The corrective excitations are the same for all deflection elements of the defective multipole element.

A method comprising the irradiation of a wafer by an ion beam that passes through an implantation filter, the ion beam being electrostatically deviated in a first direction and a second direction in order to move the ion beam over the wafer, and the implantation filter being moved in the second direction to match the movement of the ion beam.

A multi-beam apparatus for observing a sample with high resolution and high throughput is proposed. In the apparatus, a source-conversion unit forms plural and parallel images of one single electron source by deflecting plural beamlets of a parallel primary-electron beam therefrom, and one objective lens focuses the plural deflected beamlets onto a sample surface and forms plural probe spots thereon. A movable condenser lens is used to collimate the primary-electron beam and vary the currents of the plural probe spots, a pre-beamlet-forming means weakens the Coulomb effect of the primary-electron beam, and the source-conversion unit minimizes the sizes of the plural probe spots by minimizing and compensating the off-axis aberrations of the objective lens and condenser lens.

A multi-beam apparatus for observing a sample with high resolution and high throughput is proposed. In the apparatus, a source-conversion unit changes a single electron source into a virtual multi-source array, a primary projection imaging system projects the array to form plural probe spots on the sample, and a condenser lens adjusts the currents of the plural probe spots. In the source-conversion unit, the image-forming means is on the upstream of the beamlet-limit means, and thereby generating less scattered electrons. The image-forming means not only forms the virtual multi-source array, but also compensates the off-axis aberrations of the plurality of probe spots.

A charged-particle source for emission of electrons or other electrically charged particles comprises, located between the emitter electrode having an emitter surface and a counter electrode, at least two adjustment electrodes; a pressure regulator device is configured to control the gas pressure in the source space at a pre-defined pressure value. In a first cleaning mode of the particle source, applying a voltage between the emitter and counter electrodes directs gas particles towards the counter electrode, generating secondary electrons which ionize particles of the gas in the source space, and electrostatic potentials are applied to at least some of the adjustment electrodes, generating an electric field directing the ionized gas particles onto the emitter surface.

A charged particle beam device includes a deflection unit that deflects a charged particle beam released from a charged particle source to irradiate a sample, a reflection plate that reflects secondary electrons generated from the sample, and a control unit that controls the deflection unit based on an image generated by detecting the secondary electrons reflected from the reflection plate. The deflection unit includes an electromagnetic deflection unit that electromagnetically scans with the charged particle beam by a magnetic field and an electrostatic deflection unit that electrostatically scans with the charged particle beam by an electric field. The control unit controls the electromagnetic deflection unit and the electrostatic deflection unit, superimposes an electromagnetic deflection vector generated by the electromagnetic scanning and an electrostatic deflection vector generated by the electrostatic scanning, and controls at least a trajectory of the charged particle beam.

A beam splitter for generating a plurality of charged particle beamlets from a charged particle source is disclosed. The beam splitter includes a plurality of beamlet deflectors, which each pass a beamlet along an optical axis. Each beamlet deflector includes a low order element and a corresponding high order element. Each low order element has fewer electrodes than each corresponding high order element; and each low order element is one of a plurality of low order elements; and each corresponding high order element is one of a plurality of high order elements.

A low voltage scanning electron microscope is disclosed, which includes: an electron source configured to generate an electron beam; an electron beam accelerator configured to accelerate the electron beam; a compound objective lens configured to converge the electron beams accelerated by the electron beam accelerator; a deflection device arranged between the inner wall of the magnetic lens and the optical axis of the electron beam and configured to deflect the electron beam; a detection device comprising a first sub-detection device for receiving secondary and backscattered electrons from the specimen, a second sub-detection device for receiving backscattered electrons, and a control device for changing the trajectories of the secondary electrons and the backscattered electrons; an electrostatic lens comprising the second sub-detection device, a specimen stage, and a control electrode for reducing the moving speed of the electron beam and changing the moving directions of the secondary and the backscattered electrons.

A low voltage scanning electron microscope is disclosed, which includes: an electron source configured to generate an electron beam; an electron beam accelerator configured to accelerate the electron beam; a compound objective lens configured to converge the electron beams accelerated by the electron beam accelerator; a deflection device arranged between the inner wall of the magnetic lens and the optical axis of the electron beam and configured to deflect the electron beam; a detection device comprising a first sub-detection device for receiving secondary and backscattered electrons from the specimen, a second sub-detection device for receiving backscattered electrons, and a control device for changing the trajectories of the secondary electrons and the backscattered electrons; an electrostatic lens comprising the second sub-detection device, a specimen stage, and a control electrode for reducing the moving speed of the electron beam and changing the moving directions of the secondary and the backscattered electrons.

According to one embodiment, provided is a deflection sensitivity calculation method for calculating deflection sensitivity of a deflector in an electron beam irradiation apparatus that irradiates an irradiation object on a stage with an electron beam by causing the deflector to deflect the electron beam, the deflection sensitivity calculation method including: irradiating an area that covers an adjustment plate with an electron beam by scanning a deflection parameter that controls deflection of the deflector in a predetermined width; detecting a current value detected from the adjustment plate; forming an image corresponding to the detected current value, a number of pixels of the image being known; calculating the number of pixels of a portion corresponding to the adjustment plate in the formed image; and calculating the deflection sensitivity of the deflector.