There is provided a charged particle beam system for reducing phase variations in a charged particle beam due to sixth order three-lobe aberration. The charged particle beam system (100) is equipped with an aberration corrector (30) for correcting aberrations in the optical system, and includes: an aberration measuring section (44) for measuring sixth order three-lobe aberration of sixth order geometric aberration, a computing section (46) for computing the magnitude of at least one of fourth order three-lobe aberration of fourth order geometric aberration and three-fold astigmatism of second order geometric aberration for reducing phase variations in the charged particle beam due to the sixth order three-lobe aberration on the basis of the measured sixth order three-lobe aberration, and a controller (48) for controlling the aberration corrector (30) to produce at least one of the fourth order three-lobe aberration and the three-fold astigmatism on the basis of the computed magnitude.

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. Further, a multipole device (100, 200) with a first multipole (110, 210) and a second multipole (120, 220) provided on the same substrate as well as a charged particle beam apparatus (500) with a multipole device (100, 200) are provided.

A multiple particle beam system with a mirror mode of operation, a method for operating a multiple particle beam system with a mirror mode of operation and an associated computer program product are disclosed. The multiple particle beam system can be operated in different mirror modes of operation which allow the multiple particle beam system to be inspected and recalibrated thoroughly. A detection system configured to operate in a first detection mode and/or in a second detection mode is used for the analysis.

An aberration corrector has two stages of dodecapole (12-pole) elements each of which has first through twelfth poles arranged in this order. Exciting coils of the (4n+1)th poles and the exciting coils of the (4n+4)th poles are connected with a first reversible power supply in series (where n=0, 1, 2) to produce magnetic fields which are identical in absolute value but mutually opposite in sense relative to the optical axis within a plane perpendicular to the axis. The exciting coils of the (4n+3)th poles and the exciting coils of the (4n+2)th poles are connected with a second reversible power supply in series to produce magnetic fields which are identical in absolute value but mutually opposite in sense relative to the optical axis within the plane perpendicular to the axis.

The present invention provides an electrode assembly comprising two or more electrodes arranged around a primary axis forming a non-cylindrical channel space. General electronic apparatus/device, particularly apparatus of charged-particle beam such as electron microscope, may use the electrode assembly to create an optimized pattern of electrical field within non-cylindrical channel space. When the electrode assembly is used as a beam deflector in a magnetic objective lens, the electrical field within the central channel space can be co-optimized with the magnetic field for reducing aberration(s) such as distortion, field curvature, astigmatism, and chromatic aberration, after the beam passes through the central channel space.

The method is for automatic astigmatism correction of a lens system. A first image of a first frequency spectrum in a microscope is provided. The first image of a view is not in focus. The first image is then imaged. A first roundness measure of a distribution and directions of intensities in the first image is determined. The lens is changed to a second stigmator setting to provide a second image of a second frequency spectrum. The second image of the view is not in focus. The second image is the same view as the first image of the view at the first stigmator setting. A second roundness measure of a distribution and directions of intensities in the second image is determined. The first roundness measure is compared with the second roundness measure. The image with the roundness measure indicating the roundest distribution is selected.

There are disclosed an aberration correction method and a charged particle beam system capable of correcting off-axis first order aberrations. The aberration correction method is for use in the charged particle beam system (100) equipped with an aberration corrector (30) which has plural stages of multipole elements (32a, 32b) and a transfer lens system (34) disposed between the multipole elements (32a, 32b). The method includes varying the excitation of the transfer lens system (34) and correcting off-axis first order aberrations.

A method of producing a corrected beam of charged particles for use in a charged-particle microscope, comprising the following steps: Providing a non-monoenergetic input beam of charged particles; Passing said input beam through an optical module comprising a series arrangement of: A stigmator, thereby producing an astigmatism-compensated, energy-dispersed intermediate beam with a particular monoenergetic line focus direction; A beam selector, comprising a slit that is rotationally oriented so as to match a direction of the slit to said line focus direction, thereby producing an output beam comprising an energy-discriminated portion of said intermediate beam.

Provided is a scanning electron microscope which can perform high-speed focus correction even when an electron beam having high energy is used. The scanning electron microscope includes an electron optical system including an electron source 100 that emits an electron beam and an objective lens 113, a sample stage 1025 which is disposed on a stage 115 and on which a sample 114 is placed, a backscattered electron detector 1023 which is disposed between the objective lens and the sample stage and is configured to detect backscattered electrons 1017 emitted due to interaction between the electron beam and the sample, a backscattered electron detection system control unit 138 which is provided corresponding to the backscattered electron detector and is configured to apply a voltage to the backscattered electron detector, and a device control calculation device 146. The objective lens has an opening in a stage direction, and the device control calculation device performs focus correction of the electron beam by controlling the voltage applied to the backscattered electron detector from the backscattered electron detection system control unit.

A secondary projection imaging system in a multi-beam apparatus is proposed, which makes the secondary electron detection with high collection efficiency and low cross-talk. The system employs one zoom lens, one projection lens and one anti-scanning deflection unit. The zoom lens and the projection lens respectively perform the zoom function and the anti-rotating function to remain the total imaging magnification and the total image rotation with respect to the landing energies and/or the currents of the plural primary beamlets. The anti-scanning deflection unit performs the anti-scanning function to eliminate the dynamic image displacement due to the deflection scanning of the plural primary beamlets.