A charged particle beam system can include a vacuum chamber, a specimen holder for holding a specimen within the vacuum chamber, and a charged particle column. The charged particle column can include a charged particle source for producing a beam of charged particles along an optical axis and a magnetic immersion lens for focusing the beam of charged particles. The magnetic immersion lens can include a first lens pole disposed adjacent a first surface of the specimen, an excitation coil surrounding the first lens pole, and a counterpole disposed adjacent a second surface of the specimen, the counterpole including one or more magnets disposed on the counterpole.

A particle beam generator for a particle beam device may be operated. A liquid metal may be provided from a container of a particle source to an emission device of the particle source and a first heating cycle for cleaning the particle source performed, which may comprise supplying a heating current to a heating device arranged at the emission device using a current supply unit, heating the emission device during a heating time period, measuring a value of a voltage drop at the heating device and/or at the current supply unit and adjusting at least one of: the heating current and the heating time period using the current supply unit, depending on the measured value of the voltage drop. A second heating cycle for cleaning the particle source may include using at least one of: the adjusted heating current and the adjusted heating time period, for heating the emission device.

A particle beam generator for a particle beam device may be operated. A liquid metal may be provided from a container of a particle source to an emission device of the particle source and a first heating cycle for cleaning the particle source performed, which may comprise supplying a heating current to a heating device arranged at the emission device using a current supply unit, heating the emission device during a heating time period, measuring a value of a voltage drop at the heating device and/or at the current supply unit and adjusting at least one of: the heating current and the heating time period using the current supply unit, depending on the measured value of the voltage drop. A second heating cycle for cleaning the particle source may include using at least one of: the adjusted heating current and the adjusted heating time period, for heating the emission device.

A particle beam system and, such as a multi-beam particle microscope, can have a current intensity of individual particle beams that is flexibly set over large value ranges without structural modifications. The particle beam system can include a condenser lens system, a pre-multi-lens array with a specific pre-counter electrode and a pre-multi-aperture plate, and a multi-lens array. The system can includes a controller to supply adjustable excitations to the condenser lens system and the pre-counter electrode so that the charged particles are incident on the pre-multi-aperture plate in telecentric manner.

A particle beam system and, such as a multi-beam particle microscope, can have a current intensity of individual particle beams that is flexibly set over large value ranges without structural modifications. The particle beam system can include a condenser lens system, a pre-multi-lens array with a specific pre-counter electrode and a pre-multi-aperture plate, and a multi-lens array. The system can includes a controller to supply adjustable excitations to the condenser lens system and the pre-counter electrode so that the charged particles are incident on the pre-multi-aperture plate in telecentric manner.

Disclosed is a charged particle optical apparatus. The charged particle optical apparatus has a liner electrode in a first vacuum zone. The liner electrode is used to generate an electrostatic objective lens field. The apparatus has a second electrode which surrounds at least a section of the primary particle beam path. The section extends in the first vacuum zone and downstream of the liner electrode. A third electrode is provided having a differential pressure aperture through which the particle beam path exits from the first vacuum zone. A particle detector is configured for detecting emitted particles, which are emitted from the object and which pass through the differential pressure aperture of the third electrode. The liner electrode, the second and third electrodes are operable at different potentials relative to each other.

Disclosed is a charged particle optical apparatus. The charged particle optical apparatus has a liner electrode in a first vacuum zone. The liner electrode is used to generate an electrostatic objective lens field. The apparatus has a second electrode which surrounds at least a section of the primary particle beam path. The section extends in the first vacuum zone and downstream of the liner electrode. A third electrode is provided having a differential pressure aperture through which the particle beam path exits from the first vacuum zone. A particle detector is configured for detecting emitted particles, which are emitted from the object and which pass through the differential pressure aperture of the third electrode. The liner electrode, the second and third electrodes are operable at different potentials relative to each other.

The device includes a beam source for generating an electron beam, a beam guiding tube passed through an objective lens, an objective lens for generating a magnetic field in the vicinity of the specimen to focus the particles of the particle beam on the specimen, a control electrode having a potential for providing a retarding field to the particle beam near the specimen to reduce the energy of the particle beam when the beam collides with the specimen, a deflection system including a plurality of deflection units situated along the optical axis for deflecting the particle beam to allow scanning on the specimen with large area, at least one of the deflection units located in the retarding field of the beam, the remainder of the deflection units located within the central bore of the objective lens, and a detection unit to capture secondary electron (SE) and backscattered electrons (BSE).

The device includes a beam source for generating an electron beam, a beam guiding tube passed through an objective lens, an objective lens for generating a magnetic field in the vicinity of the specimen to focus the particles of the particle beam on the specimen, a control electrode having a potential for providing a retarding field to the particle beam near the specimen to reduce the energy of the particle beam when the beam collides with the specimen, a deflection system including a plurality of deflection units situated along the optical axis for deflecting the particle beam to allow scanning on the specimen with large area, at least one of the deflection units located in the retarding field of the beam, the remainder of the deflection units located within the central bore of the objective lens, and a detection unit to capture secondary electron (SE) and backscattered electrons (BSE).

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.