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.

An objective lens arrangement that may include a magnetic lens and an electrostatic lens. The magnetic lens may include one or more coils, an upper polepiece and a lower polepiece. The electrostatic lens may include an upper electrode, an internal lower electrode and an external lower electrode. A majority of the internal lower electrode may be surrounded by a majority of the external lower electrode. The upper electrode, the internal lower electrode, and the external lower electrode are arranged in a coaxial relationship along an optical axis of the objective lens arrangement. An area of a bottom aperture of the external lower electrode may not exceed an area of a bottom aperture of the internal lower electrode

An objective lens arrangement that may include a magnetic lens and an electrostatic lens. The magnetic lens may include one or more coils, an upper polepiece and a lower polepiece. The electrostatic lens may include an upper electrode, an internal lower electrode and an external lower electrode. A majority of the internal lower electrode may be surrounded by a majority of the external lower electrode. The upper electrode, the internal lower electrode, and the external lower electrode are arranged in a coaxial relationship along an optical axis of the objective lens arrangement. An area of a bottom aperture of the external lower electrode may not exceed an area of a bottom aperture of the internal lower electrode

An objective lens arrangement includes a first, second and third pole pieces, each being substantially rotationally symmetric. The first, second and third pole pieces are disposed on a same side of an object plane. An end of the first pole piece is separated from an end of the second pole piece to form a first gap, and an end of the third pole piece is separated from an end of the second pole piece to form a second gap. A first excitation coil generates a focusing magnetic field in the first gap, and a second excitation coil generates a compensating magnetic field in the second gap. First and second power supplies supply current to the first and second excitation coils, respectively. A magnetic flux generated in the second pole piece is oriented in a same direction as a magnetic flux generated in the second pole piece.

An objective lens arrangement includes a first, second and third pole pieces, each being substantially rotationally symmetric. The first, second and third pole pieces are disposed on a same side of an object plane. An end of the first pole piece is separated from an end of the second pole piece to form a first gap, and an end of the third pole piece is separated from an end of the second pole piece to form a second gap. A first excitation coil generates a focusing magnetic field in the first gap, and a second excitation coil generates a compensating magnetic field in the second gap. First and second power supplies supply current to the first and second excitation coils, respectively. A magnetic flux generated in the second pole piece is oriented in a same direction as a magnetic flux generated in the second pole piece.

A charged particle beam device includes: a charged particle source that emits a charged particle beam; a boosting electrode disposed between the charged particle source and a sample to form a path of the charged particle beam and to accelerate and decelerate the charged particle beam; a first pole piece that covers the boosting electrode; a second pole piece that covers the first pole piece; a first lens coil disposed outside the first pole piece and inside the second pole piece to form a first lens; a second lens coil disposed outside the second pole piece to form a second lens; and a control electrode formed between a distal end portion of the first pole piece and a distal end portion of the second pole piece to control an electric field formed between the sample and the distal end portion of the second pole piece.

A charged particle beam device includes: a charged particle source that emits a charged particle beam; a boosting electrode disposed between the charged particle source and a sample to form a path of the charged particle beam and to accelerate and decelerate the charged particle beam; a first pole piece that covers the boosting electrode; a second pole piece that covers the first pole piece; a first lens coil disposed outside the first pole piece and inside the second pole piece to form a first lens; a second lens coil disposed outside the second pole piece to form a second lens; and a control electrode formed between a distal end portion of the first pole piece and a distal end portion of the second pole piece to control an electric field formed between the sample and the distal end portion of the second pole piece.

An electron microscope system and a method of measuring an aberration of the electron microscope system are disclosed. A method of controlling an aberration of an electron microscope includes obtaining a dispersed energy distribution for electrons at a diffraction plane of the electron microscope and placing an aperture at a selected location of the dispersed energy distribution in the diffraction plane. The method measures displacement of an image of the aperture in an image plane of the electron microscope for the selected location of the aperture. The method determines an aberration coefficient of the electron microscope from the measured displacement and the selected location of the aperture and alters a parameter of an element of the electron microscope to control the aberration of the electron microscope based at least in part on the determined aberration coefficient.

An electron microscope system and a method of measuring an aberration of the electron microscope system are disclosed. A method of controlling an aberration of an electron microscope includes obtaining a dispersed energy distribution for electrons at a diffraction plane of the electron microscope and placing an aperture at a selected location of the dispersed energy distribution in the diffraction plane. The method measures displacement of an image of the aperture in an image plane of the electron microscope for the selected location of the aperture. The method determines an aberration coefficient of the electron microscope from the measured displacement and the selected location of the aperture and alters a parameter of an element of the electron microscope to control the aberration of the electron microscope based at least in part on the determined aberration coefficient.