Abstract

A multi-beam particle microscope having an improved aberration correction unit comprising a sequence of electrode arrays comprising a first pair of electrode arrays. The first pair has first and second electrode arrays. The first electrode and second electrode arrays each has a multiplicity of geometry-based correction electrodes each having n-fold rotational symmetry about the optical axis for multipole field generation. Each of the geometry-based correction electrodes is controllable individually via exactly one feed line. The geometry-based correction electrodes in the first electrode array are rotated relative to associated geometry-based correction electrodes in the second electrode array in relation to the optical axis. The controller is designed to control the multiplicity of geometry-based correction electrodes of the first electrode array and of the second electrode array of the aberration correction unit individually for an aberration correction.

IPC Classes  ?

• H01J 37/153 - Electron-optical or ion-optical arrangements for the correction of image defects, e.g. stigmators
• H01J 37/12 - Lenses electrostatic
• H01J 37/14 - Lenses magnetic
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

A monolithic multi-aperture plate and an improved manufacturing method for a monolithic multi-aperture plate for forming a plurality of electron beams for a multi-beam electron beam system are described. The monolithic multi-aperture plate consists of a monolithically constructed element with individual functional planes, a plurality of apertures and an embedded structured metal layer for electrical connection. Apart from the plurality of apertures, the monolithic multi-aperture plate contains no cavities. The monolithic multi-aperture plate is designed for better performance and longer service life.

IPC Classes  ?

• H01J 37/09 - DiaphragmsShields associated with electron- or ion-optical arrangementsCompensation of disturbing fields

Abstract

A method for determining the image sharpness of a particle-optical image with an improved image sharpness criterion is disclosed. For this purpose, for an image data set, intensity gradients in different directions are evaluated. For the gradient images generated relative to different directions, a respective variance (Vi) per gradient image is calculated, wherein averaging from a plurality of direction-related variance values is carried out internally per gradient image. The minimum variance (Vmin), which represents a measure of the image sharpness, is ascertained from the variance values calculated per gradient image. This image sharpness criterion can also be used for an automated adjustment of imaging particle beam systems.

IPC Classes  ?

• G06T 7/00 - Image analysis

Abstract

A method for imaging of semiconductor samples with reduced charging effects and a multi-beam charged particle beam system configured for imaging of semiconductor samples with reduced charging effects comprises adjusting the kinetic energy of primary charged particles to a low energy transition energy, where charging of a material composition is minimized. The system and method include for example a monitoring system and optimization of the kinetic energy to minimize charging effects.

IPC Classes  ?

• H01J 37/317 - Electron-beam or ion-beam tubes for localised treatment of objects for changing properties of the objects or for applying thin layers thereon, e.g. ion implantation
• H01J 37/02 - Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof Details
• H01J 37/22 - Optical or photographic arrangements associated with the tube
• H01J 37/24 - Circuit arrangements not adapted to a particular application of the tube and not otherwise provided for
• H01J 37/26 - Electron or ion microscopesElectron- or ion-diffraction tubes
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

Charged particle beam devices, e.g., for repair tasks, are subject to disturbances. A sensor output of one or more sensors is used to compensate the disturbances, e.g., while executing a manipulation mode for repairing defects on a lithography mask.

IPC Classes  ?

• H01J 37/24 - Circuit arrangements not adapted to a particular application of the tube and not otherwise provided for
• H01J 37/20 - Means for supporting or positioning the object or the materialMeans for adjusting diaphragms or lenses associated with the support

Abstract

A multi-beam charged particle system and a method of operating a multi-beam charged particle system can provide improved image contrast. The multi-beam charged particle system comprises a filter element or an active array element in a detection system, which can provide improved, anisotropic image contrast. The disclosure can be applied for applications of multi-beam charged particle system, where higher desired beam uniformity and throughput may be relevant.

IPC Classes  ?

• H01J 37/153 - Electron-optical or ion-optical arrangements for the correction of image defects, e.g. stigmators
• H01J 37/073 - Electron guns using field emission, photo emission, or secondary emission electron sources
• H01J 37/09 - DiaphragmsShields associated with electron- or ion-optical arrangementsCompensation of disturbing fields
• H01J 37/14 - Lenses magnetic
• H01J 37/244 - DetectorsAssociated components or circuits therefor

Abstract

A multiple particle beam system has an arrangement comprising a pre-aperture module and a micro-optical unit module. The pre-aperture module comprises a carrier plate with a first set comprising at least two multi-aperture arrays which are identical and thus have the same action, and have the same number of apertures, the same shape and size of the apertures and the same arrangement of the apertures and thus can be exchanged one for another. A mechanism for arranging the carrier plate in the particle-optical beam path makes it possible, in the event of damage to the active multi-aperture array in particular owing to x-ray radiation, to exchange multi-aperture arrays that have the same action. The micro-optical unit module, which is arranged downstream of the pre-aperture module in the particle-optical beam path, can be thereby better protected against x-ray radiation that occurs, and can have a longer service life.

IPC Classes  ?

• H01J 37/09 - DiaphragmsShields associated with electron- or ion-optical arrangementsCompensation of disturbing fields
• H01J 37/20 - Means for supporting or positioning the object or the materialMeans for adjusting diaphragms or lenses associated with the support
• H01J 37/26 - Electron or ion microscopesElectron- or ion-diffraction tubes

Abstract

A particle beam system includes: a multi-beam particle source configured to generate a multiplicity of particle beams; an imaging optical unit configured to image an object plane in particle-optical fashion into an image plane and direct the multiplicity of particle beams on the image plane; and a field generating arrangement configured to generate electric and/or magnetic deflection fields of adjustable strength in regions close to the object plane. The particle beams are deflected in operation by the deflection fields through deflection angles that depend on the strength of the deflection fields.

IPC Classes  ?

• H01J 37/317 - Electron-beam or ion-beam tubes for localised treatment of objects for changing properties of the objects or for applying thin layers thereon, e.g. ion implantation
• H01J 37/14 - Lenses magnetic
• H01J 37/147 - Arrangements for directing or deflecting the discharge along a desired path

Abstract

A multi-beam particle microscope comprising a particle source configured to emit charged particles, and a multi-aperture arrangement configured to generate a first field of a multiplicity of charged first individual particle beams from the charged particles. A beam tube portion is arranged between the particle source and the multi-aperture arrangement. A condenser lens system with a magnetic lens can be arranged in the region of the beam tube portion. The beam tube portion comprises pure titanium or a titanium alloy, or the beam tube portion consists of pure titanium or a titanium alloy. The permeability coefficient of the pure titanium or of the titanium alloy is 1.0005 or less, such as 1.00005 or less. This can help make it possible to generate individual particle beams of better quality.

IPC Classes  ?

• H01J 37/16 - VesselsContainers
• H01J 37/09 - DiaphragmsShields associated with electron- or ion-optical arrangementsCompensation of disturbing fields
• H01J 37/14 - Lenses magnetic
• H01J 37/147 - Arrangements for directing or deflecting the discharge along a desired path
• H01J 37/244 - DetectorsAssociated components or circuits therefor
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

A particle-optical arrangement includes a magnet arrangement for separating a primary and a secondary particle-optical beam path. The magnet arrangement includes: a first magnetic field region through which the primary particle-optical beam path and the second particle-optical beam path pass, for the separation of the primary particle-optical beam path and the secondary particle-optical beam path from one another; a second magnetic field region arranged in the primary particle-optical beam path and not arranged in the secondary particle-optical beam path; and a third magnetic field region arranged in the primary particle-optical beam path and not arranged in the secondary particle-optical beam path.

IPC Classes  ?

• H01J 37/147 - Arrangements for directing or deflecting the discharge along a desired path
• H01J 37/26 - Electron or ion microscopesElectron- or ion-diffraction tubes

Abstract

A method for voltage contrast imaging, for example on a semiconductor sample, uses a corpuscular multi-beam microscope with a multiplicity of individual corpuscular beams in a grid arrangement. The method includes sweeping the multiplicity of individual corpuscular beams over a sample having at least one electrically chargeable structure, and charging the sample with a first quantity of first corpuscular beams of the corpuscular multi-beam microscope. The method also includes determining a voltage contrast at the at least one electrically chargeable structure of the sample with a second quantity of second corpuscular beams of the corpuscular multi-beam microscope.

IPC Classes  ?

• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams
• H01J 37/02 - Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof Details

Abstract

A multi-beam charged particle system and a method of operating a multi-beam charged particle system with reduced impact of charging is provided. A surface charge is reduced by filtering individual beamlets of the plurality of primary beamlets, thereby limiting a scanning image acquisition with high resolution to a region of interest and reducing a charging of surface areas outside of the region of interest. A multi-beam charged particle beam system therefor comprises filtering means such as masking blades, a deflector array, or a multi-aperture lens array.

IPC Classes  ?

• H01J 37/04 - Arrangements of electrodes and associated parts for generating or controlling the discharge, e.g. electron-optical arrangement, ion-optical arrangement
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

Various examples pertain to frame-aggregation for multiple images (1051, 1052, 1053, 154) multi-beam raster scanning microscopes. Image registration parameters can be assessed and adjusted, if required. This yields better image registration, resulting in a better quality of the overall composite image.

IPC Classes  ?

• G06T 7/30 - Determination of transform parameters for the alignment of images, i.e. image registration
• G06T 5/50 - Image enhancement or restoration using two or more images, e.g. averaging or subtraction

Abstract

Techniques of post-processing a frame-aggregation sequence of images acquired using a charged particle microscope are disclosed. A filter is applied to regulate an impact of each image of the sequence of images onto an aggregate image. In an example, one or more images at a beginning of the sequence are discarded, i.e., do not affect the aggregate image at all. This helps to reduce charging artifacts and obtaining an aggregate image having an improved image quality.

IPC Classes  ?

• G06T 5/50 - Image enhancement or restoration using two or more images, e.g. averaging or subtraction

Abstract

The invention relates to a method for producing a micro-optical unit for a multiple particle beam system, comprising the following steps: (a) providing a first plate of the micro-optical unit that is electrically conductive; (b) providing a second plate of the micro-optical unit that is electrically conductive; (c) creating a plate stack comprising stacks of the first plate of the micro-optical unit and the second plate of the micro-optical unit one above the other, wherein the first plate of the micro-optical unit and the second plate of the micro-optical unit are fixed relative to one another in the plate stack and are electrically insulated from one another; and (d) drilling through the entire created plate stack comprising at least the first plate and the second plate of the micro-optical unit, and thereby creating both a first number of apertures in the first plate of the micro-optical unit and a second number of apertures in the second plate of the micro-optical unit.

IPC Classes  ?

• H01J 37/10 - Lenses

Abstract

A multi-beam charged particle system with a secondary electron imaging system and a method of operation of the multi-beam charged particle system is provided, which is configured for a compensation of imaging or pupil aberrations over a large range of landing energies of primary charged particles. With the disclosed system and methods, a systematic approach to compensation of imaging or pupil aberrations of a secondary electron imaging system is enabled. The invention can be applied for wafer inspection with multi-beam charged particle system.

IPC Classes  ?

• H01J 37/153 - Electron-optical or ion-optical arrangements for the correction of image defects, e.g. stigmators
• H01J 37/244 - DetectorsAssociated components or circuits therefor

Abstract

A multi-beam charged particle system and a method of operating a multi-beam charged particle system with reduced impact of charging is provided. Surface charge present on a surface of a sample, which are for example generated during a first image scanning operation, is compensated during a second scanning operation in mirror mode for charge compensation.

IPC Classes  ?

• H01J 37/02 - Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof Details

Abstract

A multi-beam charged particle system can have reduced field curvature. The multi-beam charged particle system can comprise a charged particle mirror element for compensating a field curvature of charged particle imaging elements. The charged particle mirror element can be configured for generating during use a virtual reflection surface of curved shape for reflecting primary charged particles. The disclosure can be applied for applications of multi-beam charged particle system, where higher beam uniformity and throughput are desired.

IPC Classes  ?

• H01J 37/22 - Optical or photographic arrangements associated with the tube
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

A multi-beam charged particle beam system includes a multi-beam forming unit with a lower sensitivity to secondary electrons, scattered charge particles and x-ray radiation. Thereby, a plurality of primary charged particle beamlets can be generated with higher precision and with a longer lifetime of a multi-beam forming unit. The system and method are applicable for an inspection of samples, for example for wafer or mask inspection.

IPC Classes  ?

• H01J 37/09 - DiaphragmsShields associated with electron- or ion-optical arrangementsCompensation of disturbing fields
• H01J 37/26 - Electron or ion microscopesElectron- or ion-diffraction tubes

Abstract

An improvement to a multipole array for a multi-beam system is provided. At least one of an improvement regarding better evacuation, less contamination risk and increased manipulation range is achieved by at least one improvement means comprising rounded edges within vacuum gaps, deep pockets formed in conducting material, and electrodes within vacuum gaps for generating repelling or attracting forces to charged particles.

IPC Classes  ?

• H01J 37/147 - Arrangements for directing or deflecting the discharge along a desired path
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

A method is disclosed for operating a multiple particle beam system with improved performance, said multiple particle beam system operating with a plurality of first individual charged particle beams. The plurality of first individual particle beams are imaged on an object in a raster arrangement and guided over the object by means of a collective scan deflector arranged in a crossover region of the first individual particle beams. The method includes the following steps: defining a first operating point (A_1) of the multiple particle beam system comprising a first beam current (l_1); ascertaining a best first global focusing (Fg_1), by means of which the plurality of first individual particle beams can be imaged on the object at the first operating point (A_1); ascertaining a first global offset (d_1) from the best first global focusing (Fg_1) on the basis of the first beam current (l_1); ascertaining a first global detuned focusing (F_detune_1) on the basis of the first global offset (d_1); and raster scanning the object with the plurality of first individual particle beams at the first operating point (A_1) with the first global detuned focusing (F_detune_1) for a performance increase. The first global offset is determined during a calibration method wherein the digital images obtained during a focus series of a reference object are analysed to ascertain a best global focus location using two algorithms, one optimizing the sharpness and the other optimizing the contrast gradient.

IPC Classes  ?

• H01J 37/21 - Means for adjusting the focus
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

A monolithic multi-aperture plate for forming a plurality of electron beams for a multi-beam electron beam system is described. The monolithic multi-aperture plate consists of a monolithically constructed element having individual functional planes and having a plurality of apertures. Apart from the plurality of apertures, the monolithic multi-aperture plate contains no cavities. The monolithic multi-aperture plate is designed for better performance and longer service life.

IPC Classes  ?

• H01J 37/12 - Lenses electrostatic
• H01J 37/147 - Arrangements for directing or deflecting the discharge along a desired path
• H01J 37/317 - Electron-beam or ion-beam tubes for localised treatment of objects for changing properties of the objects or for applying thin layers thereon, e.g. ion implantation

Abstract

A multi-beam charged particle beam system and a method of operating a multi-beam charged particle beam system with higher precision are configured for a determination of an assignment of secondary electron focus spot to a plurality of sets of detection elements. The system and method are further configured to adjust the assignment and for a calibration of a monitoring method and system for monitoring the assignment. The system and method are applicable for an inspection of samples, for example for wafer or mask inspection.

IPC Classes  ?

• H01J 37/317 - Electron-beam or ion-beam tubes for localised treatment of objects for changing properties of the objects or for applying thin layers thereon, e.g. ion implantation
• H01J 37/147 - Arrangements for directing or deflecting the discharge along a desired path
• H01J 37/21 - Means for adjusting the focus
• H01J 37/244 - DetectorsAssociated components or circuits therefor
• H01J 37/26 - Electron or ion microscopesElectron- or ion-diffraction tubes
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

A method for operating a multi-beam particle microscope in an inspection mode of operation and an associated multi-beam particle microscope are disclosed, wherein a detection unit comprises an image generation detection region with fixedly assigned detection channels and an adjustment detection region with additional detection channels. The fixedly assigned detection channels and the additional detection channels are in the same detection plane. Based on signals obtained via the additional detection channels, it is possible to correct an incidence position of the secondary beams on the detection unit in real time, to be precise independently of the specific structure of the detection unit.

IPC Classes  ?

• H01J 37/26 - Electron or ion microscopesElectron- or ion-diffraction tubes
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

For aligning magnetic lenses in a multi-beam particle microscope, an electrically controllable mechanical alignment and fixing mechanism with an actuator system is provided for at least one global alignable magnetic lens. The mechanism is configured to mechanically align and mechanically fix a position of the at least one alignable magnetic lens in the particle optical beam path in a plane orthogonal to the optical axis of the multi-beam particle microscope. A controller is configured to electrically control the electrically controllable mechanical alignment and fixing mechanism.

IPC Classes  ?

• H01J 37/02 - Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof Details
• H01J 37/14 - Lenses magnetic
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

What is disclosed is a particle-optical arrangement for providing a primary particle-optical beam path for a plurality of first individual particle beams which, emanating from a multi-beam particle generator, are directed at an object positionable in an object plane of the arrangement, and a secondary particle-optical beam path for a plurality of second individual particle beams which emanate from the object. The particle-optical arrangement has a magnet arrangement having a first magnetic field region through which the primary particle-optical beam path and the second particle-optical beam path pass, for the separation of the primary particle-optical beam path and the secondary particle-optical beam path from one another. The magnet arrangement furthermore has a second magnetic field region arranged in the primary particle-optical beam path and not arranged in the secondary particle-optical beam path, the second magnetic field region being arranged upstream of the first magnetic field region in relation to the primary particle-optical beam path and the first magnetic field region and the second magnetic field region deflecting the primary particle-optical beam path in different directions. The first magnetic field region has an exit inclination σ1 ≠ 0°, wherein the exit inclination σ1 is defined as the angle by which the alignment of the exit region deviates from the normal to the particle-optical axis Z of the primary particle-optical beam path.

IPC Classes  ?

• H01J 37/153 - Electron-optical or ion-optical arrangements for the correction of image defects, e.g. stigmators
• H01J 37/147 - Arrangements for directing or deflecting the discharge along a desired path
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

The invention relates to a multi-beam particle beam system (1) having a better resolution and a faster recording speed. To this end, an electrostatic booster lens (112) is arranged in an upper focal plane of the objective lens (102) level with the crossover region of the primary particle beams. The electrostatic booster lens (112) is used to significantly increase the kinetic energy of the primary beams (3) in the crossover region (108) in a targeted manner, which is why the Coulomb interaction between the charged particles is reduced.

IPC Classes  ?

• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams
• H01J 37/12 - Lenses electrostatic

Abstract

A valve for a charged particle beam microscope comprises: a valve seat comprising an opening; and a valve member comprising a valve member body and a sealing ring on a first surface of the valve member body. The valve member is movable between a first position where the sealing ring seals around the opening and a second position where the valve member is spaced apart from the opening. The valve member further comprises an electrically conducting shielding member extending at least at a side surface of the valve member body facing the opening in the second position.

IPC Classes  ?

• H01J 37/18 - Vacuum locks
• H01J 37/09 - DiaphragmsShields associated with electron- or ion-optical arrangementsCompensation of disturbing fields

Abstract

A multiple particle beam system is disclosed, in particular a multi- beam particle microscope, comprising the following: a magnetic lens through which a plurality of individual charged particle beams pass; and a controller configured to control, in particular dynamically control, the magnetic lens. The magnetic lens comprises a coil (701), a winding body (702), especially with a cooling line arrangement, and a pole shoe. The coil is arranged around the winding body and the winding body is designed as a hollow body through which the plurality of individual particle beams pass. The coil, together with the winding body, is arranged within the pole shoe. The pole shoe has an opening through which a magnetic field created by the magnetic lens emerges from the pole shoe and interacts with the plurality of individual particle beams in order to obtain a lens effect. The winding body is electrically conductive and has an interruption (710), by means of which the electrical conductivity of the winding body is interrupted in the circumferential direction around the particle-optical axis. A creation of electrical eddy currents in the winding body around the particle-optical axis is reduced when the magnetic lens is controlled dynamically. As a result, the magnetic lens of the multiple particle beam system can be controlled dynamically with a large bandwidth up to 1500 Hz.

IPC Classes  ?

• H01J 37/141 - Electromagnetic lenses
• H01J 37/21 - Means for adjusting the focus
• H01F 5/02 - Coils wound on non-magnetic supports, e.g. formers

Abstract

The invention discloses multiple automated mechanical adjustment methods for a particle beam column. By way of example, a beam generator, a condenser lens system, a detection system and an objective lens system are thus able to be adjusted quickly and precisely. The mechanical adjustment methods may be combined with electrical adjustment methods.

IPC Classes  ?

• H01J 37/147 - Arrangements for directing or deflecting the discharge along a desired path
• H01J 37/18 - Vacuum locks
• H01J 37/22 - Optical or photographic arrangements associated with the tube

Abstract

A multi-beam particle microscope can reduce particle beam-induced traces on a sample at which a high voltage is present. The occurrence of additional residual gas in the sample chamber is reduced using a specific objective lens cable and/or a specific sample stage cable, which are specifically shielded.

IPC Classes  ?

• G01N 23/2251 - Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups , or by measuring secondary emission from the material using electron or ion microprobes using incident electron beams, e.g. scanning electron microscopy [SEM]
• H01J 37/09 - DiaphragmsShields associated with electron- or ion-optical arrangementsCompensation of disturbing fields
• H01J 37/10 - Lenses

Abstract

A multi-beam charged particle system and a method of operating a multi-beam charged particle system with improved throughput is provided. The multi-beam charged particle system is configured for executing a series of image acquisitions at a series of inspection sites and for determining an adjustment of an image acquisition at a subsequent inspection from previous image acquisitions at previous inspection sites. The invention can be applied to multi-beam charged particle beam system for high-throughput wafer inspection tasks.

IPC Classes  ?

• H01J 37/05 - Electron- or ion-optical arrangements for separating electrons or ions according to their energy
• H01J 37/22 - Optical or photographic arrangements associated with the tube
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams
• H01J 37/153 - Electron-optical or ion-optical arrangements for the correction of image defects, e.g. stigmators

Abstract

A multi-beam generating unit of a multi-beam charged particle imaging system can exhibit reduced sensitivity to drift and extended lifetime. Drifts due to x-ray irradiation and thermal loads can be minimized by a combination of at least one of a shielding element, a cooling member, or an architecture and method for operating an active multi-aperture element. A lifetime can be improved by annealing methods of an active multi-aperture element or a microelectronic device forming for example a voltage supply unit.

IPC Classes  ?

• H01J 37/09 - DiaphragmsShields associated with electron- or ion-optical arrangementsCompensation of disturbing fields
• H01J 37/12 - Lenses electrostatic
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

A multi-beam charged particle microscope system, having a mirror mode of operation, can be operated to record a stack of images in a mirror imaging mode. The stack of images comprises at least two images of two different settings of at least on multi-aperture element, for example a focus stack, which allows the multi-beam charged particle microscope system to be inspected and recalibrated thoroughly. Related methods computer program products are disclosed.

IPC Classes  ?

• H01J 37/147 - Arrangements for directing or deflecting the discharge along a desired path
• H01J 37/10 - Lenses
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

A multi-beam charged particle system and a method of operating a multi-beam charged particle system with improved image contrast is provided. The multi-beam charged particle system is configured for selecting a first and a second, different image acquisition property, and for acquiring a first image and a second image of a surface of a wafer with a plurality of primary charged particle beamlets. The multi-beam charged particle system is configured image processing of the first and the second images to obtain at least one processed image. The invention can be applied for applications of multi-beam charged particle system, where higher requirements on beam uniformity and throughput are necessary.

IPC Classes  ?

• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams
• H01J 37/244 - DetectorsAssociated components or circuits therefor

Abstract

A method includes operating a multiple particle beam system at different working points. The numerical aperture can be set for each of the working points in such a way that the resolution of the multiple particle beam system is optimal. In the process, the beam pitch between adjacent individual particle beams on the sample to be scanned is kept constant as a boundary condition. There are no mechanical reconfigurations of the system whatsoever for the purposes of varying the numerical aperture.

IPC Classes  ?

• H01J 37/317 - Electron-beam or ion-beam tubes for localised treatment of objects for changing properties of the objects or for applying thin layers thereon, e.g. ion implantation
• H01J 37/10 - Lenses
• H01J 37/145 - Combinations of electrostatic and magnetic lenses
• H01J 37/147 - Arrangements for directing or deflecting the discharge along a desired path
• H01J 37/26 - Electron or ion microscopesElectron- or ion-diffraction tubes
• H01J 37/302 - Controlling tubes by external information, e.g. programme control

Abstract

A multi-beam particle microscope having a quickly replaceable particle source is disclosed. To this end, the multi-beam particle microscope comprises a specific double seal-off and column separation module. By means of this double seal-off and column separation module, a replacement module with a particle source can be replaced quicker and potentially sensitive constituent parts of the particle optics of the multi-beam particle microscope can be protected from contamination.

IPC Classes  ?

• H01J 37/26 - Electron or ion microscopesElectron- or ion-diffraction tubes
• H01J 37/16 - VesselsContainers
• H01J 37/18 - Vacuum locks
• H01J 37/067 - Replacing parts of gunsMutual adjustment of electrodes

Abstract

A multi-beam particle microscope with an improved micro-optical unit for generating the multiplicity of individual beams is disclosed. The improved micro-optical unit comprises means for setting and maintaining an unchanging imaging property of the multiplicity of individual beams. In one example, the improved micro-optical unit comprises at least one measuring apparatus used to sense a change in length, a change in distance, a contamination or degradation of a component of the micro-optical unit during operation. A multi-beam particle microscope comprises a control unit which establishes an effect on at least one individual beam from a change in length, a change in distance, a contamination or degradation of the component. A multi-beam particle microscope also comprises a compensation element for compensating the effect on the at least one individual beam. According to a method for operating a multi-beam particle microscope, a remaining service life of the multi-beam particle microscope which meets a demand in respect of a wafer inspection is also established.

IPC Classes  ?

• H01J 37/04 - Arrangements of electrodes and associated parts for generating or controlling the discharge, e.g. electron-optical arrangement, ion-optical arrangement
• H01J 37/26 - Electron or ion microscopesElectron- or ion-diffraction tubes
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

A method for operating a multi-beam particle beam microscope includes: scanning a multiplicity of particle beams over an object; directing electron beams emanating from impingement locations of the particle beams at the object onto an electron converter; detecting first signals generated by impinging electrons in the electron converter via a plurality of detection elements of a first detection system during a first time period; detecting second signals generated by impinging electrons in the electron converter via a plurality of detection elements of a second detection system during a second time period; and assigning to the impingement locations the signals which were detected via the detection elements of the first detection system during the first time period, for example on the basis of the detection signals which were detected via the detection elements of the second detection system during the second time period.

IPC Classes  ?

• H01J 37/244 - DetectorsAssociated components or circuits therefor
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

Techniques are disclosed that enable determining values of one or more imaging parameters that characterize in an imaging subsystem of a multi-beam scanning electron imaging system. For instance, a distortion model can be determined for each imaging subsystem. An optical transfer function can be determined for each imaging subsystem. For determining the values of the one or more imaging parameters, multiple pairs of test images (281, 282) are acquired that both depict certain structures (51) of a sample.

IPC Classes  ?

• H01J 37/22 - Optical or photographic arrangements associated with the tube
• H01J 37/26 - Electron or ion microscopesElectron- or ion-diffraction tubes
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

A multi-beam charged particle microscope configured determines and compensates wave front aberrations. With a variation element, the wave-front aberration amplitudes are indirectly determined and transformed in normalized sensitivity units. It is possible to compensate the wave-front aberrations with a compensation element which is different from the variation element. The normalized sensitivity units can for example be determined an improved calibration method.

IPC Classes  ?

• H01J 37/153 - Electron-optical or ion-optical arrangements for the correction of image defects, e.g. stigmators

Abstract

A multi-beam charged particle system with a secondary electron imaging system is provided, which is configured for a dynamic compensation of charging effects. The multi-beam charged particle system comprises an improved cross-over detection system and a cross-over actuation mechanism, which are both connected to a contrast control module. With the system, a closed-loop control of an intensity distribution of a plurality of secondary electron beamlets within a cross-over or pupil plane is enabled. The invention can be applied for wafer inspection with multi-beam charged particle system.

IPC Classes  ?

• H01J 37/21 - Means for adjusting the focus
• H01J 37/244 - DetectorsAssociated components or circuits therefor
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams
• H01J 37/09 - DiaphragmsShields associated with electron- or ion-optical arrangementsCompensation of disturbing fields
• H01J 37/10 - Lenses
• H01J 37/145 - Combinations of electrostatic and magnetic lenses
• H01J 37/147 - Arrangements for directing or deflecting the discharge along a desired path

Abstract

The following are disclosed: a method for designing a multi-beam particle microscope and a multi-beam particle microscope operating with a multiplicity of charged individual particle beams and imaging the latter into an object plane and comprising a plurality of path trajectory correction plates. Each of the path trajectory correction plates has a multiplicity of apertures for the multiplicity of individual particle beams and exactly one settable correction voltage is applied to each of the path trajectory correction plates during the operation of the multi-beam particle microscope. A path trajectory correction plate is fixedly assigned to an operating parameter of the multi-beam particle microscope. When designing the path trajectory correction plates, the apertures in the path trajectory correction plates are adapted in view of shape and size such that operating parameter-related path deviations of all individual particle beams can be corrected.

IPC Classes  ?

• H01J 37/153 - Electron-optical or ion-optical arrangements for the correction of image defects, e.g. stigmators
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

A multi-beam generator for a charged-particle multi-beam system is provided, comprising a stack of multi-aperture plates with at least a first multi-lens array for long range focal length variation and a second multi-lens array for short range focal length variation. Aperture diameters of the second plate 352,362 in the first multi-lens array vary to encode a pre-compensation of a spherically curved image field in an object plane of the multi-beam system. Optionally, aperture diameters in the second multi-lens array vary to encode a pre-compensation of a residual image field error in the object plane which is not pre-compensated by the first multi-lens array. The control unit of the multi-beam generator provides driving voltages Ul, U2 to the first and second lens arrays based on the current working point of the charged-particle multi-beam system.

IPC Classes  ?

• H01J 37/153 - Electron-optical or ion-optical arrangements for the correction of image defects, e.g. stigmators
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

Various examples of the disclosure generally pertain to closed-loop control of one or more parameters of a multi-beam charged particle imaging system, e.g., a multi beam scanning electron microscope, mSEM. A pattern of secondary beamlets can be stabilized. A focal position can be stabilized. According to examples, fast algorithms are facilitated by a field-programmable gated array, FPGA, logic.

IPC Classes  ?

• H01J 37/244 - DetectorsAssociated components or circuits therefor
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

A method for defect detection in a sample, such as in a semiconductor sample, includes the following steps: providing a reference image of the sample; providing a sample image generated via a particle beam inspection system, wherein the sample image comprises a rotation with respect to the reference image; dividing the sample image into sample image regions; dividing the reference image into reference image regions, wherein each sample image region is assigned one reference image region to form an image region pair; identifying in each image region pair a structure that is present both in the sample image region and also in the associated reference image region of the image region pair; registering the sample image regions by correcting a lateral offset of the identified structure in each sample image region on the basis of the location of the identified structure in the respectively associated reference image region, as a result of which corrected sample image regions are formed; and comparing each corrected sample image region pixel by pixel with the respectively associated reference image region for defect detection.

IPC Classes  ?

• G06T 7/00 - Image analysis
• G06T 7/33 - Determination of transform parameters for the alignment of images, i.e. image registration using feature-based methods
• H01J 37/22 - Optical or photographic arrangements associated with the tube

Abstract

A multi-beam particle beam system comprises a particle beam source for creating a beam of charged particles, and a beam splitter for splitting the beam into a bundle of particle beams. The beam splitter comprises a multi-aperture plate having openings. A particle optical unit is provided to focus each of the particle beams in an object plane. A correction optical unit is provided for compensating for at least one aberration of the particle optical unit and comprises three or five hexapod elements and a plurality of round lens elements. The hexapod elements are successively arranged between the particle source and the multi-aperture plate in the beam path. A round lens element is arranged between each pair of hexapod elements arranged directly in succession in the beam path.

IPC Classes  ?

• H01J 37/10 - Lenses
• H01J 37/147 - Arrangements for directing or deflecting the discharge along a desired path
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

A method for operating a multi-beam particle microscope in a contrast operating mode, comprises: irradiating an object with a multiplicity of charged first individual particle beams, each first individual particle beam irradiating a separate individual field region of the object in a scanning fashion; collecting second individual particle beams emerging or emanating from the object due to the first individual particle beams; defocused projecting the second individual particle beams onto detection regions of a detection unit so that the second individual particle beams emerging or emanating from two different individual field regions are projected onto different detection regions, a plurality of detection channels being assigned to each detection region, the detection channels each encoding angle information and/or direction information of the second individual particle beams when starting from the object; and generating individual images of each individual field region based on data obtained via signals from each detection region.

IPC Classes  ?

• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams
• H01J 37/244 - DetectorsAssociated components or circuits therefor

Abstract

A system includes a multi-beam particle microscope for imaging a 3D sample layer by layer, and a computer system with a multi-tier architecture is disclosed. The multi-tier architecture can allow for an optimized image processing by gradually reducing the amount of parallel processing speed when data exchange between different processing systems and/or of data originating from different detection channels takes place. A method images a 3D sample layer by layer. A computer program product includes a program code for carrying out the method.

IPC Classes  ?

• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams
• H01J 37/26 - Electron or ion microscopesElectron- or ion-diffraction tubes

Abstract

A multi-beam particle microscope can provide improved beam current control. Excess electrons discharged from one or just a few regions of an absorber layer provided on a multi-aperture array can be measured via an ammeter. The measured currents can be used as controlled variables in a closed loop control. The measurement can be large-area and low-noise. The multi-aperture array can be specifically structured to also realize a direction sensitive detection, for example via a quadrant detector or a tertial detector.

IPC Classes  ?

• H01J 37/24 - Circuit arrangements not adapted to a particular application of the tube and not otherwise provided for
• H01J 37/10 - Lenses
• H01J 37/244 - DetectorsAssociated components or circuits therefor

Abstract

A multi-beam charged particle beam system with a secondary electron imaging system is provided, which is configured for a dynamic compensation of charging effects of a sample over a large range of landing energies of primary charged particles. The multi-beam charged particle beam system is of reduced complexity and comprises one fast electrostatic lens element and one second means for compensation of charging effects. The second means can be a second fast electrostatic lens element or a position actuator. The invention can be applied for wafer inspection with multi-beam charged particle beam system.

IPC Classes  ?

• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams
• H01J 37/12 - Lenses electrostatic
• H01J 37/141 - Electromagnetic lenses
• H01J 37/145 - Combinations of electrostatic and magnetic lenses
• H01J 37/244 - DetectorsAssociated components or circuits therefor

Abstract

A method for analyzing disturbing influences in a multi-beam particle microscope which operates using a plurality of individual charged particle beams arranged in a raster arrangement includes the following steps: providing an object; stationary scanning the object at a first position via the plurality of the individual particle beams during a predetermined irradiation time T, as a result of which latent structures are formed on the object; raster scanning the object comprising the first position with the formed latent structures via the plurality of the individual particle beams; and analyzing the latent structures.

IPC Classes  ?

• H01J 37/147 - Arrangements for directing or deflecting the discharge along a desired path
• H01J 37/04 - Arrangements of electrodes and associated parts for generating or controlling the discharge, e.g. electron-optical arrangement, ion-optical arrangement
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams
• H01J 37/304 - Controlling tubes by information coming from the objects, e.g. correction signals
• H01J 37/317 - Electron-beam or ion-beam tubes for localised treatment of objects for changing properties of the objects or for applying thin layers thereon, e.g. ion implantation

Abstract

A multi-beam particle microscope having an improved aberration correction unit for individually correcting one or more aberrations is disclosed. In this case, the aberration correction unit has a sequence of electrode arrays comprising at least one first pair of electrode arrays, wherein the first pair has a first electrode array and a second electrode array, wherein the first electrode array and the second electrode array each have a multiplicity of geometry-based correction electrodes each having n-fold rotational symmetry about the optical axis for multipole field generation, wherein each of the geometry- based correction electrodes is controllable individually by means of exactly one feed line, wherein the geometry-based correction electrodes in the first electrode array are rotated relative to associated geometry-based correction electrodes in the second electrode array in relation to the optical axis; and wherein the controller is designed to control the multiplicity of geometry-based correction electrodes of the first electrode array and of the second electrode array of the aberration correction unit individually for an aberration correction.

IPC Classes  ?

• H01J 37/153 - Electron-optical or ion-optical arrangements for the correction of image defects, e.g. stigmators

Abstract

A multi-beam generation unit for a multi-beam system has larger individual focusing power for each of a plurality of primary charged particle beamlets. The multi-beam generation unit comprises an active terminating multi-aperture plate. The terminating multi-aperture plate can be used for a larger focusing range for an individual stigmatic focus spot adjustment of each beamlet of a plurality of primary charged particle beamlets.

IPC Classes  ?

• H01J 37/317 - Electron-beam or ion-beam tubes for localised treatment of objects for changing properties of the objects or for applying thin layers thereon, e.g. ion implantation
• H01J 37/09 - DiaphragmsShields associated with electron- or ion-optical arrangementsCompensation of disturbing fields
• H01J 37/12 - Lenses electrostatic
• H01J 37/153 - Electron-optical or ion-optical arrangements for the correction of image defects, e.g. stigmators
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams
• H01J 37/30 - Electron-beam or ion-beam tubes for localised treatment of objects

Abstract

A method for imaging of semiconductor samples with reduced charging effects and a multi-beam charged particle beam system configured for imaging of semiconductor samples with reduced charging effects is provided. The reduced charging effect is achieved by adjusting the kinetic energy of primary charged particles to a low energy transition energy, where charging of a material composition is minimized. The system and method include for example a monitoring system and optimization of the kinetic energy to minimize charging effects.

IPC Classes  ?

• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

A method for operating a multi-beam particle microscope which operates using a plurality of individual charged particle beams, wherein the method includes the following steps: measuring the beam current; determining a deviation of the measured beam current from a nominal beam current; decomposing the determined deviation into a drift component and into a high-frequency component; and controlling the high-frequency component of the beam current via a first closed-loop beam current control mechanism and/or compensating an effect of the high-frequency component on a recording quality of the multi-beam particle microscope using different mechanism than a closed-loop beam current control mechanism. An electrostatic control lens arranged in the beam generating system between extractor and anode can be used as first closed-loop beam current control mechanism. Adapting an extractor voltage of the beam generating system can be avoided.

IPC Classes  ?

• H01J 37/24 - Circuit arrangements not adapted to a particular application of the tube and not otherwise provided for
• H01J 37/12 - Lenses electrostatic
• H01J 37/26 - Electron or ion microscopesElectron- or ion-diffraction tubes

Abstract

A multi-beam charged particle system and a method of operating a multi-beam charged particle system can provide improved image contrast. The multi-beam charged particle system comprises a filter element or an active array element in a detection system, which can provide improved, anisotropic image contrast. The disclosure can be applied for applications of multi-beam charged particle system, where higher requirements on beam uniformity and throughput may be relevant.

IPC Classes  ?

• H01J 37/317 - Electron-beam or ion-beam tubes for localised treatment of objects for changing properties of the objects or for applying thin layers thereon, e.g. ion implantation
• H01J 37/12 - Lenses electrostatic

Abstract

A multi -beam charged particle system and a method of operating a multi-beam charged particle system can provide improved image contrast. The multi-beam charged particle system comprises a filter element or an active array element in a detection system, which can provide improved, anisotropic image contrast. The disclosure can be applied for applications of multi-beam charged particle system, where higher requirements on beam uniformity and throughput may be relevant.

IPC Classes  ?

• H01J 37/244 - DetectorsAssociated components or circuits therefor

Abstract

RRRR ≤ 1.00005. This measure makes it possible to generate individual particle beams of better quality.

IPC Classes  ?

• H01J 37/09 - DiaphragmsShields associated with electron- or ion-optical arrangementsCompensation of disturbing fields
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

Charged particle beam devices, e.g., for repair tasks, are subject to disturbances. A sensor output of one or more sensors is used to compensate the disturbances, e.g., while executing a manipulation mode for repairing defects on a lithography mask.

IPC Classes  ?

• H01J 37/317 - Electron-beam or ion-beam tubes for localised treatment of objects for changing properties of the objects or for applying thin layers thereon, e.g. ion implantation
• H01J 37/26 - Electron or ion microscopesElectron- or ion-diffraction tubes
• H01J 37/302 - Controlling tubes by external information, e.g. programme control
• H01J 37/304 - Controlling tubes by information coming from the objects, e.g. correction signals

Abstract

A multi-beam charged particle inspection system and a method of operating a multi-beam charged particle inspection system for wafer inspection with high throughput and with high resolution and high reliability comprise a mechanism for reduction and compensation of a scanning induced aberration, such as a scanning distortion of a collective multi-beam raster scanner for beamlets propagating at an angle with respect to the optical axis of the multi-beam charged particle inspection system.

IPC Classes  ?

• H01J 37/153 - Electron-optical or ion-optical arrangements for the correction of image defects, e.g. stigmators
• H01J 37/147 - Arrangements for directing or deflecting the discharge along a desired path
• H01J 37/20 - Means for supporting or positioning the object or the materialMeans for adjusting diaphragms or lenses associated with the support
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

Multi-beam effects which reduce the accuracy, or the speed of a wafer inspection are corrected dependent on an inspection position using an improved multi-beam system and a wafer inspection method using the multi-beam system. The multi-beam system comprises a mechanism for influencing and homogenising an extraction field dependent on the inspection position, for example dependent on a distance from a wafer edge.

IPC Classes  ?

• H01J 37/153 - Electron-optical or ion-optical arrangements for the correction of image defects, e.g. stigmators
• H01J 37/244 - DetectorsAssociated components or circuits therefor
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

A multi-beam charged particle system and a method of setting a working distance WD of the multi beam charged particle system are provided. With the method, the working distance is adjusted while the imaging performance of a wafer inspection task is maintained by computing parameter values of components from predetermined calibration parameter values. The method can allow a relatively fast wafer inspection task even with a wafer stage with a fixed z-position parallel to an optical axis of the multi-beam charged particle system.

IPC Classes  ?

• H01J 37/317 - Electron-beam or ion-beam tubes for localised treatment of objects for changing properties of the objects or for applying thin layers thereon, e.g. ion implantation
• H01J 37/304 - Controlling tubes by information coming from the objects, e.g. correction signals

Abstract

A particle-optical arrangement, in particular a multi-beam particle microscope, with a magnet arrangement for separating a primary and a secondary particle-optical beam path is disclosed. The magnet arrangement has: a first magnetic field region through which the primary particle-optical beam path and the second particle-optical beam path pass, for the separation of the primary particle-optical beam path and the secondary particle-optical beam path from one another; a second magnetic field region arranged in the primary particle-optical beam path and not arranged in the secondary particle-optical beam path, the second magnetic field region being arranged upstream of the first magnetic field region in relation to the primary particle-optical beam path and the first magnetic field region and the second magnetic field region substantially deflecting the primary particle-optical beam path in different directions; a third magnetic field region arranged in the primary particle-optical beam path and not arranged in the secondary particle-optical beam path, the third magnetic field region being arranged upstream of the second magnetic field region in relation to the primary particle-optical beam path and the first and the third magnetic field region substantially deflecting the primary particle-optical beam path in the same direction. An entrance direction of the primary particle-optical beam path into the third magnetic field region and an exit direction of the primary particle-optical beam path from the first magnetic field region are parallel to one another and without an offset.

IPC Classes  ?

• H01J 37/04 - Arrangements of electrodes and associated parts for generating or controlling the discharge, e.g. electron-optical arrangement, ion-optical arrangement
• H01J 37/147 - Arrangements for directing or deflecting the discharge along a desired path
• H01J 37/21 - Means for adjusting the focus
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

A multi-beam charged particle system (1) is provided with reduced field curvature. The multi-beam charged particle system comprises a charged particle mirror element (700) for compensating a field curvature of charged particle imaging elements (102, 103.1, 103.2). The charged particle mirror element may be configured for generating during use a virtual reflection surface (1321) of curved shape for reflecting primary charged particles (3.1-3.3). The invention can be applied for applications of a multi-beam charged particle system, where higher requirements on beam uniformity and throughput are necessary.

IPC Classes  ?

• H01J 37/153 - Electron-optical or ion-optical arrangements for the correction of image defects, e.g. stigmators
• H01J 3/16 - Mirrors

Abstract

A multi-beam charged particle beam system and a method of operating a multi-beam charged particle beam system with higher precision is provided. The improvement relates to a multi-beam forming unit with a lower sensitivity to secondary electrons, scattered charge particles and x-ray radiation. Thereby, a plurality of primary charged particle beamlets can be generated with higher precision and with a longer lifetime of a multi-beam forming unit. The system and method is applicable for an improved inspection of samples, for example for wafer or mask inspection.

IPC Classes  ?

• H01J 37/09 - DiaphragmsShields associated with electron- or ion-optical arrangementsCompensation of disturbing fields

Abstract

A method for operating a multi-beam particle microscope in an inspection mode of operation and an associated multi-beam particle microscope are disclosed. A detection unit comprises an image generation detection region with fixedly assigned detection channels and an adjustment detection region with additional detection channels. The fixedly assigned detection channels (235) and the additional detection channels (235') are provided in the same detection plane (211). On the basis of signals obtained by means of the additional detection channels, it is possible to correct an incidence position of the secondary beams on the detection unit in real time, to be precise independently of the specific structure of the detection unit.

IPC Classes  ?

• H01J 37/244 - DetectorsAssociated components or circuits therefor
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

A multi-beam charged particle beam system and a method of operating a multi-beam charged particle beam system with higher precision is provided. The system and method is configured for an improved determination of an assignment of secondary electron focus spot to a plurality of sets of detection elements. The system and method is further configured to adjust the assignment and for a calibration of a monitoring method and system for monitoring the assignment. The system and method is applicable for an improved inspection of samples, for example for wafer or mask inspection.

IPC Classes  ?

• H01J 37/26 - Electron or ion microscopesElectron- or ion-diffraction tubes

Abstract

An improved alignment for magnetic lenses in a multi-beam particle microscope is disclosed. For this purpose, an electrically controllable mechanical alignment and fixing means with an actuator system is provided for at least one in particular global alignable magnetic lens, said means being configured to mechanically align and mechanically fix a position of the at least one alignable magnetic lens in the particle optical beam path in a plane orthogonal to the optical axis of the multi-beam particle microscope, and provision is made of a controller configured to electrically control the electrically controllable mechanical alignment and fixing means.

IPC Classes  ?

• H01J 37/02 - Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof Details
• H01J 37/14 - Lenses magnetic
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

The invention relates to a multi-beam particle microscope for reducing particle beam-induced traces on a sample at which a high voltage is present. The occurrence of additional residual gas in the sample chamber is reduced by the use of a specific objective lens cable and/or a specific sample stage cable, which are specifically shielded.

IPC Classes  ?

• H01J 37/248 - Components associated with high voltage supply

Abstract

A multi-beam charged particle microscope (1), comprising: at least a first collective raster scanner (110) for collectively scanning a plurality of J primary charged particle beamlets (3) over a plurality of J image subfields (31.mn); a detection unit (200) comprising a detector for detecting a plurality of J secondary electron beamlets (9), each corresponding to one of the J image subfields (31. mn); and a control (800, 820) comprising: a scan control unit (930) connected to the first collective raster scanner (110) and configured for controlling during use a raster scanning operation of the plurality of J primary charged beamlets (3) with the first collective raster scanner (110), a kernel generating unit (812) configured for generating during use a space variant filter kernel (910) for space variant distortion correction of the image subfield (31.mn), and an image data acquisition unit (810), its operation being synchronized with the operation of the detector, the scan control unit (930) and the kernel generating unit, wherein the image data acquisition unit (110) comprises for each of the J image subfields: - an analogue to digital converter (811) for converting during use an analogue data stream received from the detector into a digital data stream describing the image subfield (31.mn), - a hardware filter unit (813) that is configured to receive the digital data stream and that is configured for carrying out during use a convolution of a segment (32) of the image subfield (31.mn) with the space variant filter kernel (910), thus generating a distortion-corrected data stream, and - an image memory (814) configured for storing the distortion-corrected data stream as a 2D representation of the image subfield (31.mn).

IPC Classes  ?

• H01J 37/22 - Optical or photographic arrangements associated with the tube

Abstract

Disclosed is a multi-beam generating unit of a multi-beam charged particle imaging system with reduced sensitivity to drift and extended lifetime. Drifts due to x-ray irradiation and thermal loads are minimized by a combination of at least one of a shielding element, a cooling member, or an improved architecture and method for operating an active multi-aperture element. A lifetime is further improved by annealing methods of an active multi-aperture element or a microelectronic device forming for example a voltage supply unit.

IPC Classes  ?

• H01J 37/24 - Circuit arrangements not adapted to a particular application of the tube and not otherwise provided for
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams
• H01J 37/244 - DetectorsAssociated components or circuits therefor

Abstract

A multiple particle beam microscope and an associated method can provide a fast autofocus around an adjustable working distance. A system can have one or more fast autofocus correction lenses for adapting, in high-frequency fashion, the focusing, the position, the landing angle and the rotation of individual particle beams upon incidence on a wafer surface during the wafer inspection. Fast autofocusing in the secondary path of the particle beam system can be implemented in analogous fashion. An additional increase in precision can be attained via fast aberration correction mechanism in the form of deflectors and/or stigmators.

IPC Classes  ?

• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams
• H01J 37/21 - Means for adjusting the focus
• H01J 37/153 - Electron-optical or ion-optical arrangements for the correction of image defects, e.g. stigmators
• H01J 37/147 - Arrangements for directing or deflecting the discharge along a desired path
• H01J 37/145 - Combinations of electrostatic and magnetic lenses
• H01J 37/26 - Electron or ion microscopesElectron- or ion-diffraction tubes

Abstract

The invention relates to a multi-beam charged particle microscope system with a mirror mode of operation, a method for operating a multi-beam charged particle microscope system with a mirror mode of operation and an associated computer program product. The multi-beam charged particle microscope system can be operated to record a stack of images in a mirror imaging mode. The stack of images comprises at least two images of two different settings of at least on multi-aperture element, for example a focus stack, which allows the multi-beam charged particle microscope system to be inspected and recalibrated thoroughly.

IPC Classes  ?

• H01J 37/26 - Electron or ion microscopesElectron- or ion-diffraction tubes
• H01J 37/29 - Reflection microscopes

Abstract

A method for operating a multi-beam particle beam microscope includes: scanning a multiplicity of particle beams over an object; directing electron beams emanating from impingement locations of the particle beams at the object onto an electron converter; detecting first signals generated by impinging electrons in the electron converter via a plurality of detection elements of a first detection system during a first time period; detecting second signals generated by impinging electrons in the electron converter via a plurality of detection elements of a second detection system during a second time period; and assigning to the impingement locations the signals which were detected via the detection elements of the first detection system during the first time period, for example on the basis of the detection signals which were detected via the detection elements of the second detection system during the second time period.

IPC Classes  ?

• H01J 37/244 - DetectorsAssociated components or circuits therefor
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

A multiple particle beam system comprises a magnetic immersion lens and a detection system. A cross-over of the second individual particle beams is provided in the secondary path between the beam switch and the detection system, and a contrast aperture with a central cutout for cutting out the secondary beams is arranged in the region of the cross-over. A contrast correction lens system with a first magnetic contrast correction lens is arranged between the objective lens and the contrast aperture. The contrast correction lens system is configured to generate a magnetic field with an adjustable strength and correct beam tilts of the secondary beams in the cross-over in relation to the optical axis of the multiple particle beam system. It is possible to obtain a more uniform contrast for different individual images and the contrast can be improved overall.

IPC Classes  ?

• H01J 37/147 - Arrangements for directing or deflecting the discharge along a desired path
• H01J 37/244 - DetectorsAssociated components or circuits therefor
• H01J 37/143 - Permanent magnetic lenses

Abstract

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.

IPC Classes  ?

• H01J 37/26 - Electron or ion microscopesElectron- or ion-diffraction tubes
• H01J 37/22 - Optical or photographic arrangements associated with the tube
• H01J 37/147 - Arrangements for directing or deflecting the discharge along a desired path
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams
• H01J 37/244 - DetectorsAssociated components or circuits therefor

Abstract

A multi-beam charged particle microscope configured for an improved method of determining and compensating of wave front aberrations is provided. With a variation element, the wave-front aberration amplitudes are indirectly determined and transformed in normalized sensitivity units. With the invention, it is possible to compensate the wave-front aberrations with a compensation element which is different to the variation element. The normalized sensitivity units can for example be determined an improved calibration method.

IPC Classes  ?

• H01J 37/153 - Electron-optical or ion-optical arrangements for the correction of image defects, e.g. stigmators

Abstract

The invention relates to a method for operating a multi-beam particle microscope in a contrast operating mode, comprising the following steps: irradiating an object with a plurality of charged first individual particle beams, each first individual particle beam irradiating a separate individual field area of the object in a rasterising manner; collecting second individual particle beams, which exit the object or emanate from the object because of the first individual particle beams; projecting the second individual particle beams in a defocused manner onto detection areas of a detection unit such that the second individual particle beams exiting or emanating from two different individual field areas are projected onto different detection areas, a plurality of detection channels being assigned to each detection area, and the detection channels each encoding angle information and/or direction information of the second individual particle beams when starting from the object; and generating individual images of each of the individual field areas on the basis of data which is or has been obtained by means of signals from each of the detection areas and their respectively assigned detection channels.

IPC Classes  ?

• H01J 37/244 - DetectorsAssociated components or circuits therefor
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

A particle beam system includes a multi-source system. The multi-source system comprises an electron emitter array as a particle multi-source. The inhomogeneous emission characteristics of the various emitters in this multi-source system are correctable, or pre-correctable for subsequent particle-optical imaging, via particle-optical components that are producible via MEMS technology. A beam current of the individual particle beams is adjustable in the multi-source system.

IPC Classes  ?

• H01J 37/09 - DiaphragmsShields associated with electron- or ion-optical arrangementsCompensation of disturbing fields
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams
• H01J 37/21 - Means for adjusting the focus
• H01J 37/14 - Lenses magnetic
• H01J 37/147 - Arrangements for directing or deflecting the discharge along a desired path
• H01J 37/153 - Electron-optical or ion-optical arrangements for the correction of image defects, e.g. stigmators
• H01J 37/073 - Electron guns using field emission, photo emission, or secondary emission electron sources

Abstract

A multi-beam generation unit for a multi-beam system is provided with larger individual focusing power for each of a plurality of primary charged particle beamlets. The multi-beam generation unit comprise an active terminating multi-aperture plate. The terminating multi- aperture plate can be used for a larger focusing range for an individual stigmatic focus spot adjustment of each beamlet of a plurality of primary charged particle beamlets.

IPC Classes  ?

• H01J 37/04 - Arrangements of electrodes and associated parts for generating or controlling the discharge, e.g. electron-optical arrangement, ion-optical arrangement
• H01J 37/09 - DiaphragmsShields associated with electron- or ion-optical arrangementsCompensation of disturbing fields
• H01J 37/12 - Lenses electrostatic

Abstract

A multi-beam charged particle inspection system and a method of operating a multi-beam charged particle inspection system for wafer inspection can provide high throughput with high resolution and high reliability. The method and the multi-beam charged particle beam inspection system can be configured to extract from a plurality of sensor data a set of control signals to control the multi-beam charged particle beam inspection system and thereby maintain the imaging specifications including a movement of a wafer stage during the wafer inspection task.

IPC Classes  ?

• H01J 37/317 - Electron-beam or ion-beam tubes for localised treatment of objects for changing properties of the objects or for applying thin layers thereon, e.g. ion implantation
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams
• H01J 37/244 - DetectorsAssociated components or circuits therefor

Abstract

The invention discloses a method for defect detection in a sample, in particular in a semiconductor sample, including the following steps: providing a reference image of the sample; providing a sample image generated by means of a particle beam inspection system, wherein the sample image comprises a rotation with respect to the reference image; dividing the sample image into sample image regions; dividing the reference image into reference image regions, wherein each sample image region is assigned one reference image region to form an image region pair; identifying in each image region pair a structure that is present both in the sample image region and also in the associated reference image region of the image region pair; registering the sample image regions by correcting a lateral offset of the identified structure in each sample image region on the basis of the location of the identified structure in the respectively associated reference image region, as a result of which corrected sample image regions are formed; and comparing each corrected sample image region pixel by pixel with the respectively associated reference image region for defect detection.

IPC Classes  ?

• G06T 7/00 - Image analysis

Abstract

A multi-beam particle microscope with improved beam current control is disclosed. Excess electrons discharged from one or just a few regions of an absorber layer provided on a multi- aperture array are measured by means of an ammeter. The measured currents are used as controlled variables in a closed loop control. The measurement is large-area and low-noise. The multi-aperture array can be specifically structured to also realize a direction sensitive detection, for example by means of a quadrant detector or a tertial detector.

IPC Classes  ?

• H01J 37/09 - DiaphragmsShields associated with electron- or ion-optical arrangementsCompensation of disturbing fields
• H01J 37/244 - DetectorsAssociated components or circuits therefor
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

A method for operating a multi-beam particle microscope which operates using a plurality of individual charged particle beams, said method including the following steps: measuring the beam current; determining a deviation of the measured beam current from a nominal beam current; decomposing the determined deviation into a drift component and into a high-frequency component; and controlling the high-frequency component of the beam current by means of a first closed-loop beam current control means and/or compensating an effect of the high-frequency component on a recording quality of the multi-beam particle microscope using different means than a closed-loop beam current control means. An electrostatic control lens arranged in the beam generating system between extractor and anode can be used as first closed-loop beam current control means, as a result of which it is not necessary to adapt an extractor voltage of the beam generating system.

IPC Classes  ?

• H01J 37/09 - DiaphragmsShields associated with electron- or ion-optical arrangementsCompensation of disturbing fields
• H01J 37/244 - DetectorsAssociated components or circuits therefor
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

A method for analyzing disturbing influences in a multi-beam particle microscope which operates using a plurality of individual charged particle beams arranged in a raster arrangement, wherein the method includes the following steps: providing an object; stationary scanning the object at a first position by means of the plurality of the individual particle beams during a predetermined irradiation time T, as a result of which latent structures are formed on the object; raster-scanning the object comprising the first position with the formed latent structures by means of the plurality of the individual particle beams; and analyzing the latent structures.

IPC Classes  ?

• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams
• H01J 37/26 - Electron or ion microscopesElectron- or ion-diffraction tubes

Abstract

A method includes: providing position data for a plurality of areas on the sample which are to be inspected; providing a first raster arrangement of the plurality of individual particle beams, with a single field of view on the sample assigned to each individual particle beam; defining the position of a nominal scanning area in each single field of view in relation to the first raster arrangement, with the dimensions of the nominal scanning area smaller than the complete single field of view; determining an individual position deviation between a nominal scanning area and the area to be inspected for the at least one individual particle beam; changing the first raster arrangement based on the determined individual position deviation to produce a second raster arrangement of the plurality of individual particle beams; and area-wise scanning the sample using the plurality of individual particle beams in the second raster arrangement.

IPC Classes  ?

• H01J 37/26 - Electron or ion microscopesElectron- or ion-diffraction tubes
• H01J 37/153 - Electron-optical or ion-optical arrangements for the correction of image defects, e.g. stigmators
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams

Abstract

A particle beam system includes a multiple beam particle source to generate a multiplicity of charged individual particle beams, and a multi-pole lens sequence with first and second multi-pole lens arrays. The particle beam system also includes a controller to control the multi-pole lenses of the multi-pole lens sequence so related groups of multi-pole lenses of the multi-pole lens sequence through which the same individual particle beam passes in each case altogether exert an individually adjustable and focussing effect on the respective individual particle beam passing therethrough.

IPC Classes  ?

• H01J 37/141 - Electromagnetic lenses
• H01J 37/21 - Means for adjusting the focus
• H01J 37/153 - Electron-optical or ion-optical arrangements for the correction of image defects, e.g. stigmators

Abstract

A multi-beam charged particle inspection system and a method of operating a multi-beam charged particle inspection system for wafer inspection with high throughput and with high resolution and high reliability is provided. The method and the multi-beam charged particle beam inspection system comprises means for reduction and compensation of a scanning induced aberration, such as a scanning distortion of a collective multi-beam raster scanner for beamlets propagating at an angle with respect to the optical axis of the multi-beam charged particle inspection system.

IPC Classes  ?

• H01J 37/147 - Arrangements for directing or deflecting the discharge along a desired path
• H01J 37/153 - Electron-optical or ion-optical arrangements for the correction of image defects, e.g. stigmators

Abstract

Certain improvements of multi-beam raster units such as multi-beam generating units and multi-beam deflector units of a multi-beam charged particle microscopes are provided. The improvements include design, fabrication and adjustment of multi-beam raster units including apertures of specific shape and dimensions. The improvements can enable multi-beam generation and multi-beam deflection or stigmation with higher precision. The improvements can be relevant for routine applications of multi-beam charged particle microscopes, for example in semiconductor inspection and review, where high reliability and high reproducibility and low machine-to-machine deviations are desirable.

IPC Classes  ?

• H01J 37/147 - Arrangements for directing or deflecting the discharge along a desired path
• H01J 37/09 - DiaphragmsShields associated with electron- or ion-optical arrangementsCompensation of disturbing fields

Abstract

Multi-beam effects which reduce the accuracy, or the speed of a wafer inspection are corrected dependent on an inspection position using an improved multi-beam system and an improved wafer inspection method using the multi-beam system. To this end, the improved multi-beam system comprises means for influencing and homogenising an extraction field dependent on the inspection position, for example dependent on a distance from a wafer edge.

IPC Classes  ?

• H01J 37/153 - Electron-optical or ion-optical arrangements for the correction of image defects, e.g. stigmators
• H01J 37/244 - DetectorsAssociated components or circuits therefor
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams
• H01J 37/29 - Reflection microscopes

Abstract

A multi-beam charged particle system and a method of setting a working distance WD of the multi beam charged particle system is provided. With the method, the working distance is adjusted while the imaging performance of a wafer inspection task is maintained by computing parameter values of components from predetermined calibration parameter values. The method allows a fast wafer inspection task even with a wafer stage with a fixed z- position parallel to an optical axis of the multi-beam charged particle system.

IPC Classes  ?

• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams
• H01J 37/21 - Means for adjusting the focus
• H01J 37/22 - Optical or photographic arrangements associated with the tube
• H01J 37/05 - Electron- or ion-optical arrangements for separating electrons or ions according to their energy
• H01J 37/244 - DetectorsAssociated components or circuits therefor

Abstract

A multi-beam charged particle microscope and a method of operating a multi-beam charged particle microscope for wafer inspection with high throughput and with high resolution and high reliability are provided. The method of operation and the multi-beam charged particle beam microscope comprises a mechanism for a synchronized scanning operation and image acquisition by a plurality of charged particle beamlets according a selected scan program, wherein the selected scan program can be selected according an inspection task from different scan programs.

IPC Classes  ?

• H01J 37/22 - Optical or photographic arrangements associated with the tube
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams
• H01J 37/147 - Arrangements for directing or deflecting the discharge along a desired path
• H01J 37/244 - DetectorsAssociated components or circuits therefor
• H01J 37/26 - Electron or ion microscopesElectron- or ion-diffraction tubes

Abstract

A particle beam system, such as a multi-beam particle microscope, includes a multi-beam deflection device and a beam stop. The multi-beam deflection device is arranged in the particle-optical beam path downstream of the multi-beam generator and upstream of the beam switch of the particle beam system. The multi-beam deflection device serves collectively blanks a multiplicity of charged individual particle beams. These impinge on a beam stop, which is arranged in the particle-optical beam path level with a site at which a particle beam diameter is reduced or is at a minimum. By way of example, such sites are the cross-over plane of the individual particle beams or an intermediate image plane. Associated methods for operating the particle beam system and associated computer program products are disclosed.

IPC Classes  ?

• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams
• H01J 37/04 - Arrangements of electrodes and associated parts for generating or controlling the discharge, e.g. electron-optical arrangement, ion-optical arrangement
• H01J 37/147 - Arrangements for directing or deflecting the discharge along a desired path
• H01J 37/244 - DetectorsAssociated components or circuits therefor
• H01J 37/317 - Electron-beam or ion-beam tubes for localised treatment of objects for changing properties of the objects or for applying thin layers thereon, e.g. ion implantation

Abstract

A method for voltage contrast imaging, for example on a semiconductor sample, uses a corpuscular multi-beam microscope with a multiplicity of individual corpuscular beams in a grid arrangement. The method includes sweeping the multiplicity of individual corpuscular beams over a sample having at least one electrically chargeable structure, and charging the sample with a first quantity of first corpuscular beams of the corpuscular multi-beam microscope. The method also includes determining a voltage contrast at the at least one electrically chargeable structure of the sample with a second quantity of second corpuscular beams of the corpuscular multi-beam microscope.

IPC Classes  ?

• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams
• H01J 37/02 - Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof Details

Abstract

A multiple particle beam microscope and an associated method set a desired focal plane with an optical resolution and set a telecentric irradiation with the plurality of the primary beams. A method determines an optimal setting plane, into which an object surface is brought. Further, a system provides an improved resolution and telecentric irradiation for a large number of primary beams. Targeted selection and targeted individual influencing of individual primary beams and/or a mechanism means for influencing the plurality of primary beams in collective fashion can be implemented.

IPC Classes  ?

• H01J 37/21 - Means for adjusting the focus
• G01N 21/95 - Investigating the presence of flaws, defects or contamination characterised by the material or shape of the object to be examined
• H01J 37/26 - Electron or ion microscopesElectron- or ion-diffraction tubes

Abstract

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.

IPC Classes  ?

• H01J 37/145 - Combinations of electrostatic and magnetic lenses
• H01J 37/10 - Lenses
• H01J 37/147 - Arrangements for directing or deflecting the discharge along a desired path
• H01J 37/26 - Electron or ion microscopesElectron- or ion-diffraction tubes
• H01J 37/302 - Controlling tubes by external information, e.g. programme control
• H01J 37/317 - Electron-beam or ion-beam tubes for localised treatment of objects for changing properties of the objects or for applying thin layers thereon, e.g. ion implantation

Abstract

A method includes operating a multiple particle beam system at different working points. The numerical aperture can be set for each of the working points in such a way that the resolution of the multiple particle beam system is optimal. In the process, the beam pitch between adjacent individual particle beams on the sample to be scanned is kept constant as a boundary condition. There are no mechanical reconfigurations of the system whatsoever for the purposes of varying the numerical aperture.

IPC Classes  ?

• H01J 37/317 - Electron-beam or ion-beam tubes for localised treatment of objects for changing properties of the objects or for applying thin layers thereon, e.g. ion implantation
• H01J 37/10 - Lenses
• H01J 37/145 - Combinations of electrostatic and magnetic lenses
• H01J 37/147 - Arrangements for directing or deflecting the discharge along a desired path
• H01J 37/26 - Electron or ion microscopesElectron- or ion-diffraction tubes
• H01J 37/302 - Controlling tubes by external information, e.g. programme control

Abstract

A charged particle beam system includes a charged particle source that generates a first charged particle beam and a multi beam generator that generates a plurality of charged particle beamlets from an incoming first charged particle beam. Each individual beamlet is spatially separated from other beamlets. The charged particle beam system also includes an objective lens that focuses incoming charged particle beamlets in a first plane so that a first region in which a first individual beamlet impinges in the first plane is spatially separated from a second region in which a second individual beamlet impinges in the first plane. The charged particle beam system also includes a projection system and a detector system including a plurality of individual detectors. The projection system images interaction products leaving the first region within the first plane due to impinging charged particles onto a first detector and images interaction products leaving the second region in the first plane onto a second detector.

IPC Classes  ?

• H01J 37/14 - Lenses magnetic
• H01J 37/05 - Electron- or ion-optical arrangements for separating electrons or ions according to their energy
• H01J 37/147 - Arrangements for directing or deflecting the discharge along a desired path
• H01J 37/21 - Means for adjusting the focus
• H01J 37/244 - DetectorsAssociated components or circuits therefor
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams
• H01J 37/06 - Electron sourcesElectron guns

Abstract

The invention relates to a multiple particle beam microscope and an associated method with a fast autofocus around an adjustable working distance. Proposed is a system having one or more fast autofocus correction lenses for adapting, in high-frequency fashion, the focusing, the position, the landing angle and the rotation of individual particle beams upon incidence on a wafer surface during the wafer inspection. Fast autofocusing in the secondary path of the particle beam system can be implemented in analogous fashion. An additional increase in precision can be attained by means of fast aberration correction means in the form of deflectors and/or stigmators.

IPC Classes  ?

• H01J 37/21 - Means for adjusting the focus
• H01J 37/26 - Electron or ion microscopesElectron- or ion-diffraction tubes
• H01J 37/28 - Electron or ion microscopesElectron- or ion-diffraction tubes with scanning beams