Mesh Completeness Check

Abstract

To ease an issue that damages which a blocking element causes on a sample can be prevented only partially.SOLUTION: The present application relates to a method for characterizing a blocking element (C) of a particle beam device (100) for blocking the electric field between the position of a sample and a particle beam source (101). The method includes arranging means (S1, S2, and S3) for characterizing the blocking element on a side of the blocking element which faces the position of the sample.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] This application claims priority to German Patent Application DE 10 2022 209 644.4, "Mesh Integrity Check", filed with the German Patent and Trademark Office on September 14, 2022. In this regard, reference is made to the application DE 10 2022 209 644.4, the content of which is incorporated herein by reference.

[0002] The present invention relates to a method for characterizing a shielding element of a particle beam device, means for characterizing a shielding element, a particle beam device, and a corresponding computer program.

Background Art

[0003] Devices are known in which a particle beam from a particle beam source is directed towards a sample. For example, by supplying a particle beam, a sample during a process can be observed (e.g., by an electron microscope). However, the sample can also be irradiated by a particle beam in a particle beam induced process (e.g., particle beam induced etching and / or deposition).

[0004] Here, it is known to arrange a shielding element between the sample and the particle beam source. The shielding element can be used, for example, to spatially limit an electric field originating from the sample. For this reason, by arranging the shielding element at a certain distance (as close as possible) from the sample, the influence of the electric field on the incident particle beam can be kept low. In particular, when the particle beam has charged particles (e.g., electrons and / or ions), a shielding element can be used because it can interact with the electric field and this interaction can be spatially limited by the shielding element, so that, for example, uncontrolled beam deflection of the particle beam is minimized.

[0005] DE102020124307A describes an apparatus for analyzing and / or processing a sample with a particle beam. This apparatus has a shielding element for shielding the electric field generated by the charge accumulated in the sample, and this shielding element has a through-opening through which the particle beam passes to reach the sample.

[0006] However, the shielding element does not necessarily have to be in a suitable target state. For example, abnormalities from the target state can occur during normal operation in the assembly and / or maintenance of the apparatus. For example, the shielding element may have defects and / or deformations that can damage the sample. To avoid this, for example, inferring abnormalities by observing the shielding element with a particle beam is a procedure known so far. However, it is not possible to access all regions of the shielding element with a particle beam, which means that the shielding element cannot necessarily be analyzed accurately.

[0007] Therefore, with the existing methods, damage to the sample caused by the shielding element can only be partially prevented.

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Summary of the Invention

[0009] Therefore, an object of the present invention is to alleviate this problem.

[0010] This object is at least partially achieved by various aspects of the present invention.

[0011] A first aspect relates to a method for characterizing a shielding element of a particle beam apparatus for shielding an electric field between a sample position and a particle beam source. The method includes arranging means for characterizing the shielding element on a side of the shielding element facing the sample position.

[0012] In this way, the present invention can make the side of the shielding element facing the sample accessible and enable characterization of the shielding element.

[0013] The side of the shielding element facing the sample may also be referred to as the sample side. Also, in this specification, the side of the shielding element facing the particle beam source may also be referred to as the incident side of the shielding element since a particle beam from the particle beam source can be incident thereon.

[0014] Therefore, this method can enable advantageous characterization of the shielding element. For example, with previous techniques, at most only the surface of the incident side of the shielding element could be characterized (e.g., by image recording with a particle beam). However, an abnormality (e.g., a defect) on the incident side of the shielding element does not necessarily damage the sample during operation. For example, a defect on the incident side (e.g., a particle disposed on the incident side) is disposed between the shielding element and the particle beam source rather than between the sample and the shielding element, so there may be cases where it cannot mechanically affect the sample. For this reason, characterization of the incident side does not necessarily provide all the information necessary to determine whether the shielding element can damage the sample during operation. In the case of characterizing only the incident side, the characteristics of the sample side can only be determined to a certain extent by reconstruction. However, the shielding element may include sub-regions or be configured as a whole such that the sample side cannot be reconstructed. In this case, characterization of the incident side of the shielding element will be carried out "in the dark" regarding abnormalities on the sample side.

[0015] However, in reality, it is considered that the cause of damage to the sample is an abnormality on the surface of the shielding element on the sample side. This is because it can directly interact with the surface of the sample. First, since the surface of the shielding element on the sample side directly faces the surface of the sample, a direct interaction occurs. Second, during the operation of the particle beam apparatus, the shielding element is typically placed in the vicinity of the sample. This can spatially limit the influence of, for example, an electric field originating from the sample on the particle beam. However, due to the proximity, the sample is much more likely to be damaged or impaired by an abnormality on the sample side of the shielding element. For example, an abnormality on the sample side of the shielding element may include a defective site that can scrape the surface of the sample. Alternatively, a defective site of the shielding element may introduce unnecessary particles onto the surface of the sample.

[0016] The present invention can enable direct and / or complete characterization on the sample side. This is because the characterization means is arranged on the sample side and access to the surface of the shielding element on the sample side is not hindered. Therefore, highly reliable information regarding the sample side of the shielding element can be obtained.

[0017] For example, the characterization means can be statically arranged in the particle beam apparatus. For example, the characterization means can be fixed (or attached) in the particle beam apparatus so that the sample side of the shielding element can be characterized (for example, without separately shifting the characterization means).

[0018] For example, the arrangement can include the initial introduction of the characterization means into the particle beam apparatus. Thereafter, the characterization means can be further arranged in the particle beam apparatus so as to be at the position of the sample side of the shielding element.

[0019] The configuration can be carried out, for example, by positioning means (e.g., a positioner) on which the characterization means is placed and / or fixed. For example, the positioning means can comprise a sample holder and / or a stage that is spatially displaceable within the particle beam apparatus. Also, for example, it is possible to firmly incorporate the characterization means into the sample holder.

[0020] In one example, the method comprises at least partially characterizing, by means of the characterization means, the side of the shielding element that faces the sample position. Thereby, the surface of the sample side of the shielding element can be suitably characterized by the arrangement of the characterization means on the sample side. The arrangement and / or characterization can occur, for example, as part of a technical evaluation, maintenance measures, technical services, etc. of the particle beam apparatus.

[0021] As an example, characterizing includes capturing the topology of the shielding element, which is captured on the side of the shielding element that faces the sample position. For example, the topology can include the height profile of the sample side of the shielding element. The height profile can at least include, for example, a first height value related to a first (spatial) coordinate and a second height value related to a second (spatial) coordinate on the sample side of the shielding element. Accordingly, the height profile can further include at least three height values, at least four height values, at least five height values, and / or at least ten height values. In other examples, instead of the height profile, it is also possible to record only a single height value as the topology (e.g., the maximum value or the minimum value).

[0022] Also, capturing the topology can include, for example, interpolation and / or extrapolation of the captured height profile.

[0023] For example, capturing the topology can also include capturing a reference plane that can function as a reference plane for the topology.

[0024] In one example, characterizing includes determining an anomaly in the topology, at least in part based on the topology and a target state of the capture topology. For example, the capture topology can be compared to the target state of the topology. For example, the target state can include a characteristic topology (e.g., a characteristic height profile) in which an anomaly has been determined from the capture topology. For example, by comparing the course of the capture height profile to the course of the target state of the height profile, it can be determined whether a defect has changed the target course as an anomaly. For example, the defect can cause a non-characteristic (local) height and / or a non-characteristic (local) depression in the topology and can indicate that. Further, the target state can also include target values of the characteristic topology (e.g., maximum and / or minimum target values of the topology, target values of the height of the characteristic topology relative to a reference plane, etc.).

[0025] In one example, characterizing includes determining whether a shielding element extends into a sample position. The sample position can include the position of a sample (or its surface) in a particle beam apparatus, and this sample position is employed, for example, during processing and / or observation of the sample. Here, the sample position can correspond to the distance between the surface of the sample at the sample position and the shielding element. The extension into the sample position can include the shielding element extending onto the surface of the sample at the sample position, or extending into the plane reached by the surface of the sample at the sample position (or extending when the sample is inserted). If it is determined that the shielding element extends into the sample position, contact between the shielding element and the sample at the sample position is assumed. The determination of whether the shielding element extends into the sample position can be based at least in part on the capture topology. For example, the sample position (or the distance of the surface of the sample at the sample position from the shielding element) can be compared to the course of the topology.

[0026] Thus, this method can be used to determine whether (or whether it has been) the shielding element is in contact with the sample at the sample position, based at least in part on the capture topology.

[0027] In one example, the characterization means comprises a sensor for measuring the topology, and the capture of the topology is based at least in part on the measurement of the topology using the sensor. Here, the sensor can be communicatively coupled to the particle beam apparatus. Also, for example, it is possible to set the sensor via the apparatus, and it is also possible to receive data (for example, the measurement result of the topology) via the particle beam apparatus. For example, the particle beam apparatus can evaluate the measurement result (for example, by an evaluation unit). Also, the sensor can be coupled to an external device (for example, via a cable and / or wirelessly). For example, in the case of this method, it is also conceivable to open the chamber of the particle beam apparatus to allow access of the characterization means to the sample side of the shielding element. Then, the sensor can be arranged within the particle beam apparatus and its cable can be connected to an external device via the open chamber. The external device can include, for example, an evaluation unit, a computer, etc.

[0028] In one example, the sensor includes a confocal sensor, and the measurement of the topology is based at least in part on the confocal measurement principle.

[0029] In one example, the sensor includes an interference sensor, and the measurement of the topology is based at least in part on the interference measurement principle.

[0030] In order to perform measurements by means of a sensor (for example, for measurements according to a confocal measurement principle and / or an interferometric measurement principle), it may be necessary to displace the sensor spatially. Thus, this method can include attaching a characterization means (for example, a sensor) to a sample and / or a sample holder. Thereby, the characterization means can be suitably arranged for the measurement of the topology. For example, a confocal measurement principle may be required in which a confocal sensor measures the surface on the sample side of the shielding element one point at a time (for example, at a defined measurement distance). Scanning the surface one point at a time is made possible by the corresponding arrangement of the characterization means, and the characterization means can be adjusted and controlled with respect to the measurement process. For example, the arrangement of the characterization means can be controlled during the measurement by the particle beam device and / or an external device if the particle beam device and / or the external device is communicatively coupled to the sensor. Furthermore, it is also conceivable to manually arrange the characterization means (for example, by an operator) for the measurement.

[0031] In one example, the characterization means can be arranged at a predetermined distance from the shielding element, and the predetermined distance corresponds to the target distance between the sample and the shielding element. In this case, the target distance can correspond to the distance from the surface on the sample side of the shielding element to the surface of the sample. And the target distance can correspond to the distance between the sample and the shielding element at a specific sample position. Thus, in this case, the characterization means can be affected by the possible effects occurring at the target distance of the sample from the shielding element. For this reason, it is possible to directly "test" by means of the characterization means whether, for example, a shielding element (as described herein) extends into the sample position.

[0032] In one example, this method further includes detecting the presence or absence of contact between the characterization means and the shielding element. It can be understood that detecting also means, for example, capturing the topology. In the case of contact, at least one topology step of the shielding element contacts the characterization means.

[0033] In one example, the detection includes detecting a contact signal that occurs in the case of contact.

[0034] In one example, the method includes positioning the characterization means at a predetermined distance from the shielding element by approaching the characterization means in the direction of the shielding element. If a contact signal is detected during the approach, further approach in the direction of the shielding element can be interrupted, for example, to prevent damage to the shielding element.

[0035] In one example, the characterization means is provided to be movable in a vertical direction (e.g., via a spring element). The approach in the direction of the shielding element can be provided in a vertical direction (with respect to the characterization means). If contact occurs during the approach, movement of the characterization means opposite to the approach movement can occur. Thus, damage to the shielding element and / or the characterization means during contact is minimized.

[0036] In one example, the characterization means is at least partially conductive, and the detection includes detecting a current flowing through the contacting characterization means and the shielding element. Here, the contact signal can be provided by a particle beam device. For example, it is conceivable to configure the device to detect contact between the shielding element and the sample and / or the sample holder. This detection can be at least partially based on detecting a current flowing through the shielding element as well as the sample and / or the sample holder during this contact. By providing at least partially conductive characterization means, this function can be used for characterizing the shielding element (as described herein). Also, the contact signal can be transmitted from the particle beam device to an external device, for example, for controlling the approach (and positioning) of the characterization means.

[0037] In one example, the method further includes moving the characterization means in a lateral direction parallel to the surface of the sample at the sample position. The lateral movement can be effected, for example, over a predetermined distance. For example, the movement after approach can occur in the lateral direction. For example, if there is no contact signal at a predetermined distance, it can be checked whether this also applies in the case of lateral movement (or after lateral movement). Also, during the lateral movement, the contact signal (or its absence) can be recorded in order to draw conclusions regarding the characteristics of the shielding element (for example, the topology of the shielding element).

[0038] In one example, the characterization means includes a contact surface that is movably provided in the lateral direction (for example, via a spring element). Capturing the topology can further include moving the characterization means from a first position to a second position by a predetermined distance (or a predetermined movement distance) in the lateral direction and determining the distance (or movement distance) of the contact surface due to the lateral movement of the characterization means.

[0039] The lateral direction in which the contact surface of the characterization means is movably provided may be perpendicular to the vertical direction (described herein) of the characterization means. Thus, the lateral direction may correspond to the horizontal direction (or horizontal axis) of the characterization means.

[0040] The movement of the characterization means can be effected (for example, specified) by a sample holder on which the characterization means can be provided. In this case, a predetermined movement distance (of the sample holder) can be input into the particle beam apparatus, and in response thereto, the characterization means (or the sample holder) is moved.

[0041] In this example, it can be determined whether a contact surface provided to be laterally movable moves along with the lateral movement of the characterization means. This is the case, for example, when a predetermined movement distance of the characterization means (substantially) corresponds to the determined movement distance of the contact surface. The surface on the sample side of the shielding element can be characterized by comparing each movement distance. In other examples, in this method, as an alternative or addition to the above, it includes testing whether the characterization means moves laterally and, along with this, the contact surface moves and / or (completely) moves (or has moved).

[0042] In one example, this method further includes detecting no contact when the contact surface has shifted by a predetermined distance. In this case, it can be presumed that the laterally movable contact surface is not affected (e.g., contacted) by the shielding element. Therefore, it can be detected that the shielding element does not (unnecessarily) contact the characterization means.

[0043] Furthermore, this method can include detecting contact when the contact surface has not shifted by a predetermined movement distance (or, for example, has not shifted at all or has not shifted significantly). In this case, it can be presumed that the laterally movable contact surface is affected (e.g., contacted) by the shielding element. Therefore, it can be detected that the shielding element (unnecessarily) contacts the characterization means. Furthermore, it is also conceivable to detect contact starting from a threshold value of the deviation between the predetermined movement distance and the determined movement distance of the contact surface. For example, contact can be detected when the movement distance of the contact surface deviates from the predetermined movement distance by at least 1%, at least 2%, at least 3%, and / or at least 5%.

[0044] In one example, determining the movement distance includes recording a first image of the reference structure of the contact surface at a first position of the characterization means, recording a second image of the reference structure of the contact surface at a second position of the characterization means, and determining the distance between the reference structure in the first image and the reference structure in the second image to determine the movement distance of the contact surface.

[0045] Here, the image can be recorded by the particle beam of the particle beam apparatus (for example, the image can include a particle beam image (for example, a scanning force electron image)). Further, the image can also be recorded by the optical system of the particle beam apparatus (for example, the image can include an optical image).

[0046] Here, the reference structure can include a suitable structure on the surface of the characterization means. For example, the reference structure may be provided on the characterization means in the manner targeted by this method. For example, the reference structure can include characteristic structures (for example, edges, surface structures, particles, etc.) on the surface of the characterization structure.

[0047] In one example, this method further includes detecting a scratch mark on the characterization means by lateral movement.

[0048] The scratch mark can be detected in situ, for example, in a particle beam apparatus. Here, for example, one and / or a plurality of particle beam images (for example, one or more scanning force electron images) can be recorded by the particle beam apparatus. Further, it is also conceivable to record one or more particle beam images perpendicular to the lateral direction (as described herein). Therefore, when there is a scratch mark, one or more particle beam images are (substantially) perpendicular to the scratch mark. When a part of the scratch mark is detected in the particle beam image, one or more particle beam images can be recorded along the scratch mark in order to completely record the scratch mark. The particle beam image can have a field of view with a length dimension of less than 4 μm, less than 6 μm, less than 10 μm, less than 20 μm, and / or less than 100 μm, for example. Here, it can be understood that the length dimension means the dimension in the x direction and thus the y direction.

[0049] In another example, it is also conceivable to detect the scuff marks by an optical system (for example, by utilizing a light beam or a photon beam). For example, since the optical system is included in the particle beam apparatus, here, the detection of the scuff marks can also occur in situ. Furthermore, it is also conceivable to perform the detection outside the apparatus by the optical system. Here, this method can include taking out the characterization means from the particle beam apparatus after the characterization (as described herein). Thereafter, for detecting the scuff marks, an analysis of the characterization means by an (external) optical system can occur.

[0050] A second aspect is a characterization means for characterizing a shielding element of a particle beam apparatus, regarding the characterization means where a shielding element for shielding an electric field is arranged between a sample position and a particle beam source. This characterization means can include a sensor for capturing the topology of the shielding element and / or a movable, preferably spring-loaded contact surface that contacts the shielding element. Furthermore, this characterization means may be configured to be attached to a sample holder of the particle beam apparatus.

[0051] For example, due to the shape of the characterization means, a tight coupling with the sample holder can be ensured. In another example, the lower surface of the characterization means can be intended for a secure attachment to the sample holder (for example, by corresponding unevenness that can reliably support the adhesion to the sample).

[0052] Furthermore, for example, the characterization means may be configured to be attached to a sample that can be attached to a sample holder of the apparatus.

[0053] For example, the sample can include a mask blank. The mask blank can include, for example, a mask blank for a mask in (micro and / or nano) lithography (for example, i-line lithography, DUV lithography, EUV lithography, etc.). The particle beam apparatus can be configured to observe and / or process a lithography mask (for example, for mask repair).

[0054] In one example, this characterizing means further comprises a base, and the contact surface is preferably movably coupled to the base perpendicular to the contact surface via a spring element. For example, the base may include a frame structure. Here, the lower surface of the frame structure may be arranged opposite to the contact surface. At least one spring element for coupling the contact surface perpendicular to the base (or the lower surface of the base) may be provided on this lower surface. For example, the spring element can include a spring. Also, a spring system consisting of two or more springs is conceivable. Further, the frame structure can include a side structure provided perpendicular to the lower surface. For example, the side structure can extend from the lower surface such that the side structure and the lower surface form an integral structure. The side structure can include a holding region formed parallel to the contact surface in the region of the contact surface. The holding region can at least partially (securely) surround the contact surface in its peripheral region. The holding region can be used to limit the deflection of the contact surface in the vertical direction starting from the lower surface. For example, the spring element may be configured such that a (prescribed) force is applied vertically through the contact surface to the holding region. Thus, a contact surface defined in one plane can be ensured, but when a vertical force is applied, it may also create in the direction of the lower surface. Due to the creation of the contact surface, the shielding element is thus somewhat protected, which can be advantageous in the case of contact with the shielding element (for example, an approaching shielding element as described herein).

[0055] In one example, the contact surface is preferably movably coupled to the base along the plane of the contact surface via a spring element. For example, the contact surface can be coupled to the side structure of the base via a spring element. This can ensure the suspension of the contact surface in a plane perpendicular to the plane of the contact surface or the side structure. Thus, the contact surface can be movably provided parallel to the plane of the lower surface. This enables the detection of contact during the lateral movement of the characterization means (as described herein). For example, if the contact surface is held or fixed by contact with a shielding element, the base of the characterization means can continue to move along the plane of the contact surface due to the movable coupling. However, the movement of the contact surface will be (at least partially) impeded. Thus, when there is contact, the movement distance of the base will not correspond to the movement distance of the contact surface. In this way, the presence or absence of contact (as described herein) may be inferred.

[0056] In one example, the contact surface has a first plane and a second plane with respect to the base, the first plane being below the second plane, and the second plane being dimensioned to coincide with the surrounding area of the shielding element. The spatial arrangement of the planes can be referenced to the base (e.g., the lower surface of the base). Thus, the lower first plane can be at a greater distance from the shielding element than the upper second plane (when used in the method described herein). In the method described herein, a safety margin is made possible by the two planes. For example, when arranging the characterization means at a predetermined distance from the shielding element, a predetermined distance can be selected with respect to the surface of the first plane. Thus, irregularities in the surrounding area of the shielding element are more likely to be detected via the second plane. This is because the second plane is closer to the shielding element than the first plane. In particular, the second plane may contact the shielding element earlier than normal during approach (as described herein).

[0057] For example, the shielding element can (usually) comprise a holding element for the surrounding area. The holding element can have a geometrically wider structure than other elements of the shielding element, for example, and can act as a connecting element of the shielding element. For example, the holding element may be configured to fix a relatively thin mesh structure to the inner region of the shielding element. For example, the holding element can preferably have a topology that extends into the sample position (for example, in contrast to other elements of the shielding element). For example, the holding element may be shaped such that its surface is closer to the sample position (or the sample holder) than the shielding element. Thus, defects or anomalies in the region of the holding element (i.e., the surrounding region) may more likely affect the sample at the sample position.

[0058] Also, the asymptotic change between the second and the first planes can take into account the inclination of the shielding element and / or the sample during operation. In the case of inclination, for example, contact between the shielding element and the sample in the surrounding region of the shielding element is expected. Thus, due to the asymptotic change, the upper second plane can act as a safety margin. If the characterization means does not detect contact at a predetermined distance from the shielding element (starting from the surface of the first element), this can also be assumed, for example, to be the case of a slight inclination. This is because the second plane does not cause any contact at the predetermined distance.

[0059] It should also be noted that the first element can be dimensioned, for example, to match the mesh structure (or the central region) of the shielding element.

[0060] It should also be noted that one aspect of the present invention includes the use of at least one of the characterization means according to the second aspect as the characterization means in the method according to the first aspect.

[0061] Another aspect relates to the use of a sensor configured to measure the topology as the characterization means in the method according to the first aspect.

[0062] A third aspect relates to a particle beam apparatus for irradiating a sample with a particle beam, the particle beam apparatus comprising a shielding element for shielding an electric field, the shielding element being arranged between the sample position and the particle beam source, and characterization means for characterizing the shielding element according to the second aspect, the characterization means being arranged on a side of the shielding element facing the sample position. The particle beam apparatus can include, for example, a particle beam apparatus for repairing a lithography mask. For example, the particle beam apparatus may be configured to perform mask repair (e.g., as part of an automatic, semi-automatic, and / or manual repair process).

[0063] The characterization means can be incorporated in the particle beam apparatus, for example, permanently or over a long period of time. However, the characterization means may also be included in the particle beam apparatus for a short period or a defined period as part of the characterization of the shielding element (as described herein).

[0064] The particle beam source of the particle beam apparatus can emit a particle beam including, for example, charged particles (e.g., electrons and / or ions). Further, the particle beam apparatus may be configured to observe the sample with the particle beam (e.g., by electrons for recording an electron image). Further, the particle beam apparatus may be configured for particle beam induced etching of the sample and / or particle beam induced deposition of a material on the sample (e.g., as part of mask repair). For example, the particle beam apparatus can be used for repairing masks for EUV lithography, DUV lithography, and / or other types of lithography methods.

[0065] A fourth aspect relates to a computer program including instructions that, when executed by a computer and / or the particle beam apparatus according to the third aspect, cause the computer and / or the particle beam apparatus to execute the method according to the first aspect.

[0066] As an alternative or addition to the above, the computer program may include instructions for performing other method steps described herein or for performing or implementing the functions of an apparatus (or system) as described herein. For example, the computer program may cause certain components (or means) of the apparatus (or system) to be controlled in an open loop or closed loop manner such that the steps of the above method and / or the functions of the above apparatus can be (automatically) performed. Thus, the apparatus can be controlled in an open loop and / or closed loop manner based on the computer program as well as the interface to the components (or means) of the apparatus.

[0067] A fifth aspect relates to a particle beam apparatus for irradiating a sample with a particle beam, the particle beam apparatus including the computer program according to the fourth aspect. For example, the particle beam apparatus can comprise a (non-volatile) memory including (or storing) the computer program. The particle beam apparatus of the fifth aspect can include, for example, the particle beam apparatus according to the third aspect and characterization means (as described herein).

[0068] Another aspect relates to an apparatus as described herein, the apparatus having a memory including a computer program for at least partially automated control of the apparatus. Further, an apparatus of one aspect can have means for executing the computer program. Alternatively, it is also possible to store the computer program in another location (e.g., the cloud), and it is also possible for the apparatus to have only means for receiving instructions resulting from the execution of the program in another location. In any case, this enables the above method to be executed automatically or autonomously, for example, within a system and / or apparatus. For this reason, for example, intervention by manual means can be minimized, and the complexity during the operation of the apparatus (or system) can be reduced.

[0069] Furthermore, it is also conceivable to generate a protocol when one of the methods described herein is executed. The protocol can include, for example, one of the parameters described herein in the above method (for example, the position of the characterization means, the capture topology, the control signal, etc.). And the protocol can, for example, enable the execution of the above method later (for example, as part of error evaluation, auditing, service actions, etc.) and enable the acquisition of its details (for example, the position of the characterization means). The protocol can include, for example, a protocol file (for example, a log file) that can be stored in a device and / or a computer.

[0070] The features (and examples) of the method (or computer program) described herein may be adapted to and applied corresponding to the aforementioned device (or system), or may be applicable. The features (and examples) of the device (or system) described herein may be adapted to and applied corresponding to the method (or computer program) described herein, or may be applicable.

[0071] The following detailed description describes the technical background information and examples of the present invention with reference to the drawings.

Brief Description of the Drawings

[0072]

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DETAILED DESCRIPTION OF THE INVENTION

[0073] FIG. 1 is a schematic side view of a particle beam device having a shielding element and a sample at a sample position. The particle beam device 100 can include a particle beam source 101. The particle beam source 101 can emit, for example, a directed particle beam E. The particle beam E can include charged particles (for example, electrons and / or ions). The particle beam device can further include means for controlling the particle beam E in a manner that targets it (for example, directed towards deflection, focusing, correction, etc. of the targeted particle beam E). In this case, the particle beam E can be directed towards the sample M. FIG. 1 shows an exemplary sample position of the sample M.

[0074] The device 100 can have a shielding element C between the particle beam source 101 and the sample position. The shielding element C can be used to shield an electric field that can originate from the sample M. The electric field can be generated, for example, by charges accumulated on the sample by the irradiation of the particle beam E. For example, since the introduced charges are not necessarily discharged through the sample holder, the electric field can be generated from the sample M. The electric field can be restricted by the shielding element C to the space between the sample M and the shielding element C. For this reason, the particle beam E (or its charged particles) can be shielded from the electric field in the region between the shielding element C and the particle beam source 101. Thus, an uncontrolled offset of the particle beam can be prevented. The shielding element can be designed, for example, as disclosed in DE102020124307A1.

[0075] The shielding element C can include a mesh element N. The mesh element N can include one or more openings. For example, the mesh element N can include an opening in the form of a single pinhole aperture. For example, the shielding element C can also include one or more openings in the form of one or more meshes, for example. The openings of the mesh element N can include any shape (e.g., circular, polygonal, square, hexagonal, honeycomb shape, etc.). The openings of the mesh element N can have a dimension of less than 50 micrometers in at least one direction. Also, it is conceivable that the openings of the mesh element N have a dimension of less than 30 micrometers, less than 20 micrometers, or less than 10 micrometers in at least one direction. Preferably, the dimension of the openings of the mesh element N can be in the range of 5 μm to 30 μm in at least one direction. Furthermore, the characteristics of the plurality of openings of the mesh element N can be different from each other (for example, the first opening can be a circular opening with a diameter of 50 μm, and the second opening can be a circular opening with a diameter of 10 μm).

[0076] The material for forming the mesh can be made conductive in order to enable shielding of the electric field. For example, the material of the mesh element N can include at least one of gold, nickel, palladium, platinum, and iridium. For example, the thickness of the mesh element N can be in the range of 1 nm to 100 μm, 10 nm to 100 μm, 100 nm to 50 μm, 1 μm to 30 μm, 5 μm to 15 μm.

[0077] The shielding element C can further include a holding element H. The mesh element N can be fixed to the holding element H. The holding element H can widen at least one spatial dimension compared to the mesh element N. Thereby, stable fixation of the mesh element N to the holding element H can be made possible.

[0078] A through-hole 102 can be disposed at the center of the mesh element N. Its characteristics can correspond to the characteristics described herein for the openings of the mesh element N. For example, the through-hole 102 can have a dimension of less than 50 μm in at least one direction. For example, the particle beam E can be aligned to be incident on the sample M through the through-hole 102. The through-hole 102 can include a mesh defined herein (e.g., including a defined opening), which is specifically configured to allow the particle beam E to pass through. Further, the through-hole 102 (or the region of the mesh element N in the region of the through-hole 102) can be convex and curved on the sample side. Also, the region of the mesh element N where the through-hole 102 is disposed can be designed in the form of a triangle or a triangular pyramid (e.g., the apex of the triangle or triangular pyramid points to the sample / sample holder side). For example, in this case, the through-hole 102 can include the apex of the triangle or triangular pyramid.

[0079] The mesh element N can have a diameter of, for example, at least 1 mm, at least 2 mm, at least 3 mm, at least 5 mm, and / or at least 10 mm. The diameter is defined from the first side of the holding element H to the opposite side of the holding element H, and the mesh element N may be provided therebetween.

[0080] The sample M may be disposed at a predetermined sample distance d0 from the shielding element C. In the example of FIG. 1, the predetermined sample distance d0 is defined as the shortest distance between the through-hole 102 as a reference point of the shielding element C and the surface of the sample M. However, it is also conceivable to define the predetermined sample distance d0 using any other reference point of the shielding element C.

[0081] The predetermined sample distance d0 can correspond to the target distance of the sample M from the shielding element. The target distance d0 can correspond to the operating distance at which the sample is processed. For example, the target distance can be at least 5 μm, at least 10 μm, at least 15 μm, at least 20 μm, and / or at least 50 μm. Also, the target distance can have a specified value in the range of, for example, 5 μm to 100 μm.

[0082] For example, the particle beam device 100 may be configured for repairing the sample M. When processing the sample, for example, particle beam induced etching and / or deposition may be performed, and the sample can be observed by the particle beam.

[0083] For example, the particle beam device 100 can include a mask repair device. In this case, the sample M can include a lithography target. For example, the sample M can include a lithography mask suitable for any lithography method (for example, EUV lithography, DUV lithography, i-line lithography, nanoimprint lithography, etc.). In one example, the lithography mask can include an EUV mask, a DUV mask, an i-line lithography mask, and / or a nanoimprint stamp. Also, the lithography target can include a binary mask (for example, a chromium mask, an OMOG mask), a phase mask (for example, a chromium-free phase mask, an alternating phase mask (for example, a rim phase mask)), a halftone phase mask, a tritone phase mask, and / or a reticle (for example, with a pellicle). The lithography mask can be used, for example, in a lithography method for the production of semiconductor chips.

[0084] FIG. 2 is a schematic side view of a defect D of a shielding element extending into a sample M. For example, the defect D may be located in the region on the sample side of the holding element H of the shielding element C. Thus, the defect D cannot be detected by the particle beam E. The defect D can be caused, for example, by manufacturing errors, service acts, and / or maintenance measures. In FIG. 2, the sample M is arranged at a target distance d0 from the shielding element C. However, at this operating distance, there is a possibility that the defect D may come into contact with the sample M. That is, in this case, the shielding element C and the sample M come into unnecessary contact. This contact may cause a local force to act on the surface of the sample M. This means that a defective site K may be brought about on the sample M by the contact. The defective site K can include, for example, scratches and / or local depressions. However, in an industrial environment, it may be necessary to reliably prevent damage to the sample. For example, this is very important in mask repair, and if not prevented, there is also a possibility that the defective site may be transferred to the wafer in lithography. Furthermore, the uncontrolled contact K between the sample M and the shielding element C may also cause damage to the shielding element C. Therefore, contact of the sample at the target distance from the shielding element should be avoided. This can be ensured by the characterization of the shielding element C according to the invention described herein.

[0085] FIG. 3 is a schematic side view of a first means for characterizing a shielding element. The first means can comprise a confocal sensor S1 (for example, can be designed as a confocal sensor S1). The confocal sensor S1 can be attached to a sample M. The sample M can include an (unstructured) mask blank for a lithography mask. For example, the confocal sensor S1 can be attached to the sample M via a coupling means (for example, an adhesive, an adhesive layer, etc.). It is also possible to loosely place the confocal sensor S1 on the sample M. For example, it is also conceivable to roughen the lower surface of the confocal sensor S1 to ensure a stable (for example, no lateral sliding of the sensor) arrangement of the confocal sensor S1. The confocal sensor S1 can be arranged on the side opposite to the sample position of the shielding element for the purpose of characterization. Thus, defective sites can be reliably detected. In particular, defects on the sample side of the holding element H of the shielding element C can be detected. The confocal sensor S1 can be arranged by a sample holder to which the sample M provided with the confocal sensor S1 is attached. The confocal sensor S1 can generally be configured to be accommodated in the sample holder.

[0086] In particular, the confocal sensor S1 can enable measurement of the topology on the sample side of the shielding element C. The confocal sensor S1 can be used to perform measurements according to the confocal measurement principle. For this purpose, the confocal sensor S1 can include a light source that can focus the light L onto the shielding element C as measurement light. Further, the confocal sensor S1 can include a detector that detects the light reflected by the shielding element C. The detector and the light source can include components necessary for the confocal measurement principle. For example, the detector can have a pinhole aperture for the intermediate image plane to enable confocal measurement. For example, by deflecting the beam of the light L, scanning of each point on the surface of the shielding element C for confocal measurement can be performed. Further, depending on the arrangement of the confocal sensor S1, it is also conceivable to perform scanning point by point. Here, as shown in FIG. 3, the confocal sensor S1 can be arranged at a measurement distance d from the sample side of the shielding element C. Thereafter, the confocal sensor S1 can be displaced along a lateral direction parallel to the surface of the sample at the sample position. Here, in FIG. 3, the lateral direction is indicated by the x-axis. Thus, due to the lateral arrangement of the confocal sensor S1, scanning of each point on the sample-side surface of the shielding element C becomes possible. The confocal sensor S1 can be communicatively coupled to an external device and / or a particle beam device via the cable 301. For example, in this way, the arrangement for confocal measurement and the adjustment of sensor incorporation can be ensured.

[0087] In one example, the confocal sensor S1 is connected to an external device. The external device may be coupled to the particle beam device such that the sample holder of the particle beam device can be controlled accordingly by the external device in confocal measurement. In another example, only the sample holder is coupled to the external device, and confocal measurement for scanning can be performed by being controlled by the external device. In another example, the confocal sensor S1 is communicatively coupled to the particle beam device. Here, the sample holder can be controlled by the particle beam device for confocal measurement.

[0088] Furthermore, it is also conceivable that the first means includes sensors other than the confocal sensor S1. For example, an interference sensor can also be used, and accordingly, the topology can be incorporated based on the interference measurement principle. Also conceivable is an optical sensor (e.g., a CCD sensor) capable of recording an optical image of the shielding element. Furthermore, combinations of different sensors included in the first characterizing means are also conceivable. For example, for this purpose, a plurality of sensors can be provided on the sample M. For example, a plurality of measurements according to each applicable measurement principle may be used.

[0089] Figure 4 is a schematic side view of the second characterizing means at a predetermined distance d0 from the shielding element C without defects. The second means can include a first micro-structure S2. The first micro-structure S2 can include a base 401. The base 401 can include a lower surface 410 that can be present, for example, on a sample holder. The base 401 can be in the form of a frame structure, for example, as shown in Figure 4. The micro-structure S2 can include a contact surface 402 coupled to the base 401 in the vertical direction (along the z-axis of Figure 4). In the characterization, during the process, the contact surface 402 can contact the shielding element C (as described herein). The contact surface 402 can be coupled to the base 401 in the vertical direction (perpendicular to the lower surface 410) via a first spring F1 and a second spring F2. When a force in the direction of the lower surface 410 is applied to the contact surface, the contact surface may flex or move in the direction of the lower surface 410 accordingly.

[0090] In this regard, the contact surface 402 can include a first plane E1 and a second plane E2. The first plane E1 can be disposed below the second plane E2 (with respect to the lower surface of the base 401 or the specified z-direction). The first plane E1 can be dimensioned such that at the characterization position of the characterizing means, it is on the opposite side of the central region of the mesh element N of the shielding element C. The second plane E2 can be dimensioned to coincide with the peripheral region of the shielding element C (including, for example, the holding element H and a partial region of the mesh element N) at the characterization position. Thus, the dimensioning of the planes can be matched to the dimensions of the shielding element.

[0091] The first micro-structure S2 can further include a side structure 403. The side structure 403 can extend vertically from the lower surface 410 of the base 401. The side structure 403 can include a holding area 404 formed in the area of the contact surface 402 (as described herein). The holding area 404 can be dimensioned to fit precisely with the contact surface 402. The contact surface 402 can be fixed in a defined manner (in the z direction) via the holding area 404. This is because the holding area 404 can spatially limit the movement of the contact surface in the positive direction of the z-axis (for example, the movement in the positive direction of the z-axis can be brought about by the force of the first spring F1 and / or the second spring F2).

[0092] The first micro-structure S2 can be (at least partially) conductive. For this reason, the first micro-structure S2 can enable a method (as described herein). For example, the presence or absence of contact of the first micro-structure at a predetermined distance from the shielding element can be detected by the first micro-structure S2. The predetermined distance (for example, the target distance of the sample during sample processing by a particle beam apparatus) can be selected with respect to the first plane E1, for example, to take into account an inclination and / or a safety margin (as described herein).

[0093] FIG. 5 is a schematic side view of a second characterization means at a predetermined distance from the shielding element having the defect D. In this example, the first micro-structure S2 is brought closer to the shielding element C in the z-direction. The defect D of the shielding element C contacts the contact surface 402 at a predetermined sample distance d0. However, it is also conceivable to design such that the defect D contacts the contact surface 402 even at a sample distance greater than the predetermined sample distance d0. As described herein, current can flow through the shielding element C and the first micro-structure S2 by contact. For example, the current can flow from the sample holder through the first micro-structure S2 and through the shielding element C to the particle beam device 100. When current flows, the presence of this contact or contact signal can thus be determined. Therefore, further approach to the shielding element C can be interrupted. This method can include, for example, determining the z-position of the first micro-structure S2 in the case of contact and determining the sample distance accordingly. For this purpose, for example, the sample distance at which the actual sample will contact the shielding element can be determined. Further, this method can include realizing the repair and / or evaluation of the shielding element C based on the presence of contact at a predetermined sample distance (or a greater sample distance).

[0094] Figure 6 is a schematic side view of a third characterization means at a predetermined distance from a shielding element without defects. The third means can include a second micro-structure S3. Similar to the first micro-structure S2, the second micro-structure S3 can include a base 601. For example, the second micro-structure S3 can similarly include a side structure 603 and a holding region 604. The second micro-structure S3 can have a contact surface 602. The contact surface 602 can be movably coupled to the base 601 along the plane of the contact surface 602. In Figure 6, the contact surface 602 is provided to be movable in the x-direction (or the lateral direction L). The movable provision can be brought about, for example, by at least one spring element. For this reason, the second micro-structure S3 can include a first lateral spring F1' and a second lateral spring F2'. The first lateral spring F1' can be provided between the first side of the side structure 603 and the first peripheral region of the contact surface 602. Accordingly, the second lateral spring F2' can be provided on the opposite side of the second micro-structure S3, between the second side of the side structure and the second peripheral region of the contact surface 602. In this way, the contact surface 602 can be provided to be movable in the lateral direction L via the springs F1' and F2'.

[0095] Furthermore, all the features of the first micro-structure S2 can be included in the micro-structure S3 (and vice versa). For this reason, for example, in Figure 6, it can be seen that, similar to the first micro-structure S2, the contact surface 602 also has a first plane and a second plane. It should be noted that the contact surface 602 can also be provided to be movable in the z-direction (perpendicular to the lower surface of the base 601). For example, this can be made possible by a spring system as illustrated and described in Figure 5.

[0096] In the example of FIG. 6, the contact surface 602 is disposed at a predetermined sample distance d0 from the shielding element. In this example, initially, there are no defects or abnormalities in the shielding element C. Here, when the entire second micro-structure S3 moves a predetermined distance in the x direction from the first position to the second position, the contact surface moves accordingly. For example, the entire micro-structure S3 can move together with the sample holder. As a result, the base 601 advances by a certain distance and the contact surface 602 advances by a certain distance. If there is no contact between the shielding element C and the contact surface 602, the perturbation force in the x direction does not affect the contact surface 602, so the two advancing distances can be the same. This is evident in FIG. 6. This is because the contact surface 602 is symmetrically arranged with respect to the base. However, for example, if a defect in the shielding element C extends into the sample position, the contact surface 602 may be affected. By detecting this, the sample side of the shielding element can be characterized.

[0097] And FIG. 7 is a schematic side view of a third characterization means at a predetermined distance from a shielding element having a defect D. The defect D can interact with the contact surface 602 by extending into the sample position. The defect D can, for example, exert an opposite action on the contact surface 602 during movement in the x direction. However, due to the presence of the springs F1' and F2', the defect D may not be able to exert an opposite action on the movement of the base 601, or may only exert a minimal action. FIG. 7 can show the state after the second micro-structure S3 has moved a predetermined distance in the x direction (or the lateral direction). It can be seen that the contact surface has not moved the same distance as the base 601 accordingly. Therefore, the contact surface 602 is no longer symmetrically arranged with respect to the base 601. It is also clear that the second lateral spring F2' can be compressed by the obstruction of the movement of the contact surface 602 in the x direction. In contrast, the first lateral spring F1' is extensible.

[0098] The difference between the movement distance of the contact surface 602 and the movement distance of the base 601 can be brought about as described herein. For example, the base 601 can be moved by a defined distance from a first position to a second position by a sample holder. The distance traveled by the contact surface in this process can be traced, for example, by comparing the particle beam image of the contact surface at the first position and the particle beam image of the contact surface at the second position (as described herein). The particle beam image can be recorded by the particle beam E, and for example, a scanning electron image can be recorded.

[0099] Furthermore, the second micro-structure S3 can be (at least partially) conductive. Therefore, a contact signal based on the current flowing through the shielding element C and the second micro-structure S3 (as described herein) can also be detected.

[0100] FIG. 8 is a schematic plan view of the analysis of a scratch mark K on a means for characterizing a shielding element C by a particle beam apparatus 100. The analysis of the scratch mark can be carried out as an alternative or addition to a characterization method by the second and / or third characterization means (as described herein). An exemplary method can include first moving the characterization means so that a scratch mark is generated as needed. For example, the characterization means can first be placed at a predetermined sample distance (i.e., the target distance) from the shielding element C. This initial position may be associated with a zero x value and a zero y value, and the x and y directions may be parallel to the surface of the characterization means. Then, the characterization means can move to a first positive x position (e.g., x = +val). Then, the characterization means can move to a second negative x position (e.g., x = -val) having, for example, the same absolute value as the first x position. The absolute value of the first or second x position may correspond to the length that the shielding element C extends. For example, the length (and width) of the shielding element C can be in the range of 1 mm to 10 mm. In this way, the characterization means can be shifted, for example, by ±x (e.g., ±3 mm, ±4 mm, ±10 mm in the x direction) with respect to the length (or width) of the shielding element. And the analysis of the scratch mark K can be carried out along the y-axis, perpendicular to the x direction. Thus, this analysis can be carried out perpendicular to the "scratch direction". In particular, this analysis can be carried out in situ by the particle beam apparatus 100 with one or more particle beam images. If a scratch mark K is detected, it can be assumed that the shielding element C comes into contact with a sample at a predetermined sample distance. Thus, the presence of contact can be detected as part of the characterization of the shielding element.

[0101] Note that, for example, the field of view I of the particle beam apparatus 100 may be smaller than the length dimension of the shielding element C. For example, the field of view I can be in the micrometer range (for example, 1 μm × 1 μm, 6 μm × 6 μm, 10 μm × 10 μm, etc.), while the length dimension of the shielding element C can be in the millimeter range (as described in this specification). In this case, although the particle beam image can be recorded across the field of view I, it does not cover the entire length of the possible scratch mark K. To completely record the surface exposed to the shielding element C during the "scrubbing process", a large number of particle beam images are required. For example, since the surface needs to be recorded in a two-dimensional pixel format, it will take a very long time.

[0102] However, according to an exemplary method, if contact exists, it can be assumed that the scratch mark extends (substantially) along a certain direction (for example, the x direction). Only the associated position (for example, the Y position) perpendicular to it is unknown.

[0103] Therefore, in this method, lines perpendicular to the x direction (i.e., perpendicular to the possible scratch mark K) can be analyzed across multiple particle beam images. For example, this line may be defined along the y direction at x = 0. Thus, multiple particle beam images can be recorded over a length L perpendicular to the scrubbing direction. When a partial region of the scratch mark is detected in the particle beam image, accordingly, the scratch mark K can be traced, for example, through other images in the direction of the scratch mark. By moving the characterization means ±x along the length of the shielding element C, if there is contact that causes the scratch mark K, it can be guaranteed that the scratch mark K intersects the y coordinate of the length region of the shielding element C. Therefore, even when the field of view is limited, the scratch mark K can be preferably found and analyzed by evaluating the line in the y direction. Also note that it is possible to introduce, for example, a non-scrubbing mask blank as the characterization means into the particle beam apparatus.

Description of Reference Numerals

[0104] 100 Particle beam apparatus 101 Particle beam source 102 Through-opening 301 Cable 401 Base 402 Contact surface 403 Side structure 404 Holding area 410 Bottom surface 601 Base 602 Contact surface 603 Side structure 604 Holding area C Shielding element D Defect E Particle beam E1 First plane E2 Second plane F1 First spring F1’ First lateral spring F2 Second spring F2’ Second lateral spring H Holding element I Field of view K Defective part, scratch L Light, lateral direction, length M Sample N Mesh element S1 Confocal sensor S2 First micro-structure S3 Second micro-structure d0 Predetermined sample distance d Measurement distance

Claims

1. A method for characterizing a shielding element (C) of a particle beam apparatus (100) for shielding an electric field between a sample position and a particle beam source (101), comprising: arranging means (S1, S2, S3) for characterizing the shielding element on a side of the shielding element facing the sample position; characterizing at least partially, by the characterizing means (S1, S2, S3), a side of the shielding element (C) facing the sample position; including; wherein the characterizing includes capturing a topology of the shielding element (C), and the topology is captured on a side of the shielding element facing the sample position.

2. A method for characterizing a shielding element (C) of a particle beam apparatus (100) for shielding an electric field between a sample position and a particle beam source (101), comprising: arranging means (S1, S2, S3) for characterizing the shielding element on a side of the shielding element facing the sample position; characterizing at least partially, by the characterizing means (S1, S2, S3), a side of the shielding element (C) facing the sample position; including; wherein the characterizing includes capturing a topology of the shielding element (C), and determining an abnormality of the topology at least partially based on the topology and a target state of the captured topology.

3. A method for characterizing a shielding element (C) of a particle beam apparatus (100) for shielding an electric field between a sample position and a particle beam source (101), comprising: arranging means (S1, S2, S3) for characterizing the shielding element on a side of the shielding element facing the sample position; characterizing at least partially, by the characterizing means (S1, S2, S3), a side of the shielding element (C) facing the sample position; including; wherein the characterizing further includes determining whether the shielding element extends into the sample position.

4. The method according to claim 1, wherein the characterizing means comprises a sensor (S1) for measuring the topology, and the capturing of the topology is at least partially based on the measurement of the topology using the sensor.

5. The method according to claim 4, wherein the sensor (S1) includes a confocal sensor, and the measurement of the topology is at least partially based on a confocal measurement principle.

6. The method according to claim 4 or 5, wherein the sensor (S1) includes an interference sensor, and the measurement of the topology is at least partially based on an interference measurement principle.

7. The method according to any one of claims 1 to 2, wherein the characterizing means (S2, S3) is arranged at a predetermined distance from the shielding element, and the predetermined distance corresponds to a target distance (d0) between the sample and the shielding element.

8. The method according to claim 7, further comprising detecting the presence or absence of contact between the characterizing means and the shielding element.

9. The method according to claim 8, wherein the characterizing means is at least partially conductive, and the detection includes detecting a current flowing through the characterizing means and the shielding element in the presence of the contact.

10. The method according to claim 7, further comprising moving the characterizing means (S2, S3) in a lateral direction (L) parallel to the surface of the sample at the sample position.

11. The characterizing means (S3) includes a contact surface (602) provided movably in the lateral direction (L), The capturing of the topology moving the characterizing means from a first position to a second position by a predetermined distance in the lateral direction, determining the distance of the contact surface due to the lateral movement of the characterizing means, The method according to claim 10, further comprising.

12. detecting the absence of the contact when the contact surface (602) is shifted by the predetermined distance, detecting the presence of the contact when the contact surface is not shifted by the predetermined distance, The method according to claim 8, further comprising.

13. The determination of the distance recording a first image of a reference structure of the contact surface at the first position of the characterizing means, recording a second image of the reference structure of the contact surface at the second position of the characterizing means, determining the distance between the reference structure in the first image and the reference structure in the second image to determine the distance of the contact surface, The method according to claim 11, including.

14. The method according to claim 10, further comprising detecting a scratch mark (K) on the characterizing means due to the movement in the lateral direction (L).

15. Characterization means for characterizing a shielding element (C) of a particle beam apparatus, the shielding element being arranged to shield an electric field between a sample position and a particle beam source (101), the characterization means comprising: a sensor (S1) for capturing the topology of the shielding element; characterization means configured to be attached to a sample holder of the particle beam apparatus. **Claim 16**: Characterization means for characterizing a shielding element (C) of a particle beam apparatus, the shielding element being arranged to shield an electric field between a sample position and a particle beam source (101), the characterization means comprising: a sensor (S1) and a base (401, 601) for capturing a movable, preferably spring-loaded contact surface (402, 602) that contacts the shielding element; configured to be attached to a sample holder of the particle beam apparatus; characterization means in which the contact surface (602) is movably coupled to the base (601) along a plane of the contact surface (602), preferably via a spring element. **Claim 17**: Characterization means for characterizing a shielding element (C) of a particle beam apparatus, the shielding element being arranged to shield an electric field between a sample position and a particle beam source (101), the characterization means comprising: a sensor (S1) and a base (401, 601) for capturing a movable, preferably spring-loaded contact surface (402, 602) that contacts the shielding element; configured to be attached to a sample holder of the particle beam apparatus; the contact surfaces (402, 602) having a first plane (E1) and a second plane (E2) with respect to the base (401, 601); the first plane being below the second plane; characterization means in which the second plane is dimensioned to coincide with a peripheral region of the shielding element. **Claim 18** The characterization means according to claim 16 or 17, wherein the contact surface (402, 602) is movably coupled to the base perpendicular to the contact surface, preferably via a spring element. **Claim 19** A particle beam apparatus for irradiating a sample with a particle beam, comprising: a shielding element (C) for shielding an electric field, the shielding element (C) being arranged between a sample position and a particle beam source (101); and characterization means for characterizing the shielding element according to claim 15, the characterization means being arranged on a side of the shielding element facing the sample position. A particle beam device comprising

20. A particle beam device for irradiating a sample with a particle beam, A shielding element (C) for shielding an electric field, the shielding element (C) disposed between the sample position and the particle beam source (101); Characterization means for characterizing the shielding element according to claim 16, the characterization means disposed on the side of the shielding element facing the sample position; A particle beam device comprising

21. A particle beam device for irradiating a sample with a particle beam, A shielding element (C) for shielding an electric field, the shielding element (C) disposed between the sample position and the particle beam source (101); Characterization means for characterizing the shielding element according to claim 17, the characterization means disposed on the side of the shielding element facing the sample position; A particle beam device comprising

22. The particle beam device according to any one of claims 19 to 21, designed for repairing a lithography mask.

23. A computer program comprising instructions for causing the computer and / or the particle beam device according to claim 19 to execute the method according to claim 1 when executed by the computer and / or the particle beam device.

24. A computer program comprising instructions for causing the computer and / or the particle beam device according to claim 19 to execute the method according to claim 2 when executed by the computer and / or the particle beam device.

25. A computer program comprising instructions for causing the computer and / or the particle beam device according to claim 19 to execute the method according to claim 3 when executed by the computer and / or the particle beam device.

26. A computer program comprising instructions for causing the computer and / or the particle beam device according to claim 20 to execute the method according to claim 1 when executed by the computer and / or the particle beam device.

27. A computer program comprising instructions for causing the computer and / or the particle beam device according to claim 20 to execute the method according to claim 2 when executed by the computer and / or the particle beam device. A computer program comprising instructions for causing a computer and / or a particle beam apparatus according to claim 20 to execute the method according to claim 3 when executed by the computer and / or the particle beam apparatus. A computer program comprising instructions for causing a computer and / or a particle beam apparatus according to claim 21 to execute the method according to claim 1 when executed by the computer and / or the particle beam apparatus. A computer program comprising instructions for causing a computer and / or a particle beam apparatus according to claim 21 to execute the method according to claim 2 when executed by the computer and / or the particle beam apparatus. A computer program comprising instructions for causing a computer and / or a particle beam apparatus according to claim 21 to execute the method according to claim 3 when executed by the computer and / or the particle beam apparatus.

32. A particle beam apparatus for irradiating a sample with a particle beam, the particle beam apparatus comprising the computer program according to claim 23.

33. A particle beam apparatus for irradiating a sample with a particle beam, the particle beam apparatus comprising the computer program according to claim 24.

34. A particle beam apparatus for irradiating a sample with a particle beam, the particle beam apparatus comprising the computer program according to claim 25.

35. A particle beam apparatus for irradiating a sample with a particle beam, the particle beam apparatus comprising the computer program according to claim 26.

36. A particle beam apparatus for irradiating a sample with a particle beam, the particle beam apparatus comprising the computer program according to claim 27.

37. A particle beam apparatus for irradiating a sample with a particle beam, the particle beam apparatus comprising the computer program according to claim 28.

38. A particle beam apparatus for irradiating a sample with a particle beam, the particle beam apparatus comprising the computer program according to claim 29.

39. A particle beam apparatus for irradiating a sample with a particle beam, the particle beam apparatus comprising the computer program according to claim 30. A particle beam apparatus for irradiating a sample with a particle beam, the particle beam apparatus comprising the computer program according to claim 31.

Images