An electron beam apparatus addresses blanking issues resulting from sinking high-power heat onto an aperture diaphragm by evenly spreading heat on the aperture diaphragm. The apparatus can include an aperture diaphragm and a deflector that deflects the electron beam on the aperture diaphragm. The electron beam is directed at the aperture diaphragm in a pattern around the aperture. The pattern may be a circle, square, or polygon. The pattern also may include a variable locus relative to the aperture.

Applicants have found that energetic neutral particles created by a charged exchange interaction between high energy ions and neutral gas molecules reach the sample in a ion beam system using a plasma source. The energetic neutral create secondary electrons away from the beam impact point. Methods to solve the problem include differentially pumped chambers below the plasma source to reduce the opportunity for the ions to interact with gas.

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.

An ion generator includes an ion source control unit that controls a gas supply unit and a plasma excitation source in accordance with a current ion source condition and a new ion source condition to be employed subsequent to the current ion source condition, a retention time obtaining unit that obtains retention time for the current ion source condition, and a pre-treatment condition setting unit that sets a pre-treatment condition defining a pre-treatment for forming a surface layer region suitable for the new ion source condition on a plasma chamber inner wall based on the current ion source condition, the retention time, and the new ion source condition. The ion source control unit is configured to control the gas supply unit and the plasma excitation source in accordance with the pre-treatment condition when the current ion source condition is changed to the new ion source condition.

The present invention concerns a charged-particle multi-beamlet system that comprises a source of charged particles (301); a first multi-aperture plate (320) having plural apertures disposed in a charged particle beam path of the system downstream of the source; a first multi-aperture selector plate (313) having plural apertures; a carrier (340), wherein the first multi-aperture selector plate is mounted on the carrier; and an actuator (350) configured to move the carrier such that the first multi-aperture selector plate is disposed in the charged particle beam path of the system downstream of the source in a first mode of operation of the system, and such that the first multi-aperture selector plate is disposed outside of the charged particle beam path in a second mode of operation of the system. The source, the first multi-aperture plate and the carrier of the system are arranged such that a first number of charged particle beamlets is generated at a position downstream of both the first multi-aperture plate and the first multi-aperture selector plate in the first mode of operation, and that a second number of charged particle beamlets is generated at the position in the second mode of operation, wherein the first number of beamlets differs from the second number of beamlets.

A focused ion beam system is offered which can make a focal adjustment without relying on the structure of a sample while suppressing damage to the sample to a minimum. Also, a method of making this focal adjustment is offered. The focused ion beam system has an ion source for producing an ion beam, a lens system for focusing the beam onto the sample, a detector for detecting secondary electrons emanating from the sample, and a controller for controlling the lens system. The controller is operative to provide control such that the sample is irradiated with the ion beam without scanning the beam and that a focus of the ion beam is varied by varying the intensity of the objective lens during the ion beam irradiation. Also, the controller measures the intensity of a signal indicating secondary electrons emanating from the sample while the intensity of the objective lens is being varied. Furthermore, the controller makes a focal adjustment of the ion beam on the basis of the intensity of the objective lens obtained when the measured intensity of the signal indicating secondary electrons is minimal.

Aberration correction systems and charged particle microscope systems including the same. An apparatus can include a charged particle source and an optical column. The optical column can include a multipole condenser with one or more condenser quadrupole-generating elements and/or a multipole objective with a plurality of objective multipole elements. The plurality of objective multipole elements can include at least three quadrupole-generating elements and at least three octupole-generating elements configured to at least partially correct a spherical aberration of a charged particle beam. The optical column can be configured such that the charged particle beam enters the multipole objective with a non-circular beam profile and/or such that the charged particle beam is characterized by a non-circular beam profile through at least a portion of the multipole objective.

The invention relates to a transmission charged particle microscope comprising a charged particle beam source for emitting a charged particle beam, a sample holder for holding a sample, an illuminator for directing the charged particle beam emitted from the charged particle beam source onto the sample, and a control unit for controlling operations of the transmission charged particle microscope. As defined herein, the transmission charged particle microscope is arranged for operating in at least two modes that substantially yield a first magnification whilst keeping said diffraction pattern substantially in focus. Said at least two modes comprise a first mode having first settings of a final projector lens of a projecting system; and a second mode having second settings of said final projector lens.

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 and in flexibly varying observing conditions is proposed. The apparatus uses a movable collimating lens to flexibly vary the currents of the plural probe spots without influencing the intervals thereof, a new source-conversion unit to form the plural images of the single electron source and compensate off-axis aberrations of the plural probe spots with respect to observing conditions, and a pre-beamlet-forming means to reduce the strong Coulomb effect due to the primary-electron beam.