Method for operating a particle beam device, computer program product and particle beam device for carrying out the method

Abstract

The invention relates to a method for operating a particle beam device. The method comprises capturing reference images in a reference position of the sample stage, capturing images in a first position of the sample stage, capturing images in a second position of the sample stage, interpolating image shifts of the first image and a third image, each captured at a reference value, with respect to a first reference image as a function of the sample stage position, interpolating image shifts of the second reference image, a second image, and a fourth image, each captured at a beam parameter value, with respect to the first reference image as a function of the sample stage position, wherein the beam parameter value differs from the reference value, and determining a target position of the sample stage.where the interpolated image shifts are identical at the reference value and at the beam parameter value that differs from the reference value, and where the particle beam device is operated with the beam parameter having a value corresponding to the reference value and with the sample stage positioned in the target position.

Description

[0001] The invention relates to a method for operating a particle beam device. For example, the particle beam device is an electron beam device and / or an ion beam device. Furthermore, the invention relates to a particle beam device for carrying out the method.

[0002] Electron beam instruments, in particular a scanning electron microscope (hereinafter also referred to as SEM) and / or a transmission electron microscope (hereinafter also referred to as TEM), are used to examine objects (also referred to as samples) in order to obtain knowledge about the properties and behavior of the objects under certain conditions.

[0003] In a SEM, an electron beam (hereinafter also called the primary electron beam) is generated by a beam generator and focused onto the object under investigation by a beam guidance system. An objective lens is used for focusing. A deflection device guides the primary electron beam in a raster pattern across the surface of the object. The electrons of the primary electron beam interact with the object. As a result of this interaction, interaction particles and / or interaction radiation are produced. The interaction particles include electrons. Specifically, electrons are emitted by the object – so-called secondary electrons – and electrons from the primary electron beam are backscattered – so-called backscattered electrons. The interaction particles form the secondary beam and are detected by at least one particle detector.The particle detector generates detector signals which are used to create an image of the object. The image is displayed on a screen, such as a monitor. This provides a representation of the object under investigation.

[0004] Interaction radiation includes, for example, X-rays or cathodoluminescence. It is detected, for example, with a radiation detector and is used in particular to investigate the material composition of the object.

[0005] In a TEM, a primary electron beam is also generated by a beam generator and focused onto the object under investigation using a beam guidance system. The primary electron beam passes through the object. As the primary electron beam passes through the object, the electrons interact with the material. The electrons passing through the object are focused by a system containing a lens onto a fluorescent screen or a detector—for example, a camera. This system may also include a projection device. Imaging can also be performed in the scan mode of the TEM. Such a TEM is generally referred to as a STEM.Additionally, it may be possible to detect electrons backscattered from the object under investigation and / or secondary electrons emitted by the object under investigation using a further detector in order to image the object under investigation.

[0006] It is known to integrate the functions of a STEM and a SEM into a single particle beam instrument. This particle beam instrument thus enables the investigation of objects with a SEM function and / or a STEM function.

[0007] Furthermore, it is known from the prior art to analyze and / or process an object in a particle beam instrument using both electrons and ions. For example, an electron beam column, functioning as a SEM, is arranged on the particle beam instrument. Additionally, an ion beam column is arranged on the particle beam instrument. Ions are generated by an ion generator located in the ion beam column and used to process the object. For example, material is removed from the object or a material is deposited onto it. Additionally or alternatively, the ions are used for imaging. The electron beam column with the SEM function serves primarily for further investigation of the processed or unprocessed object, but also for processing the object itself.

[0008] The aforementioned prior art particle beam instruments each have a sample chamber in which an object to be analyzed and / or processed is arranged on a sample stage. It is also known to arrange several different objects simultaneously on the sample stage in order to analyze and / or process them sequentially using the respective particle beam instrument that includes the sample chamber. The sample stage is designed to be movable in order to position the object or objects in the sample chamber. For example, a relative position of the object or objects with respect to an objective lens is set. A known sample stage is designed to be movable in three mutually perpendicular directions. In addition, the sample stage can be rotated about two mutually perpendicular axes of rotation.

[0009] The above-mentioned state-of-the-art particle beam devices have at least one of the following units for adjusting the particle beam, i.e., for shaping the particle beam and / or for adjusting the direction of the particle beam: a movable aperture diaphragm, an electrostatic deflection unit and a magnetic deflection unit.

[0010] The objective lens of the known SEM will be discussed in more detail below. The objective lens of the known SEM has pole pieces in which a bore is formed. A beam guide tube is guided through this bore. The beam guide tube has an anode at one end, which is positioned opposite an electron source. The electrons of the primary electron beam are accelerated to anode potential due to a potential difference between the electron source and the anode. The anode potential is, for example, 1 kV to 20 kV relative to the ground potential of the SEM housing. Furthermore, a coil is arranged in the pole pieces to generate a magnetic field. In addition, the known objective lens includes a termination electrode, which has a first side and a second side. The first side of the termination electrode is oriented towards the object.The second side of the termination electrode is directed towards a tubular electrode, which forms the second end of the beam guide tube. The termination electrode and the tubular electrode form an electrostatic delay device. In the known objective lens, the tubular electrode, together with the beam guide tube, is at the potential of the SEM's anode, while the termination electrode and the object within the SEM are at a potential lower than the anode. This lower potential could, for example, be the ground potential of the SEM housing. Alternatively, the object and the termination electrode can be at different potentials, but these potentials are lower than the anode potential. The known objective lens thus exhibits a first electric field between the beam guide tube and the termination electrode, and a second electric field between the termination electrode and the object.The electrons of the primary electron beam are slowed down to a desired energy required for examining the object, due to the electrostatic deceleration device.

[0011] To obtain a good image of the object—that is, an image with good resolution and the desired contrast—using the known SEM, the object should be aligned on the sample stage so that the second electric field between the object and the terminal electrode is as rotationally symmetric as possible. If the surface of the object to be imaged with the SEM is nearly flat, this surface should be aligned parallel to the terminal electrode to achieve this. However, the surface of the object to be imaged is usually not flat. To obtain a good image in this case as well, it is known to wobble an applied voltage on the object and simultaneously align the object by tilting the sample stage during the wobble.The term "wobbling" the object voltage refers to setting the applied voltage to the object to a specific value and then periodically changing this value. During this wobbling process, the object is tilted on the sample stage to align it so that the image of the object displayed on the screen either remains stationary or exhibits minimal movement. This procedure—wobbling the applied voltage and aligning the object by tilting the sample stage to a position where the image is minimally deflected or stationary—neutralizes the deflecting effect of the second electric field between the terminal electrode and the object.

[0012] The procedure described above, however, fails to consider the first electric field between the beam guide tube and the termination electrode, as well as the magnetic field generated by the objective lens. Both the first electric field and the magnetic field should be taken into account; otherwise, the primary electron beam will be deflected by both fields to such an extent that a good image cannot be achieved. To account for the first electric field, it is known to sweep the cathode voltage of the electron source. In other words, the cathode voltage is set to a specific value and then periodically varied.The primary electron beam, directed towards the object, is aligned during the aforementioned sweep of the cathode voltage by moving the aperture diaphragm and / or by deflection using an electrostatic and / or magnetic deflection unit, such that the image of the object displayed on the screen either remains stationary or exhibits minimal movement. Alternatively, to account for the magnetic field, the objective lens current is swept. In other words, the objective lens current is set to a specific value and then periodically changed.Here too, the primary electron beam, directed towards the object, is aligned during the aforementioned wobble of the objective lens current by moving the aperture diaphragm and / or by deflection using an electrostatic and / or magnetic deflection unit, such that the image of the object displayed on the screen either remains stationary or exhibits minimal movement. However, due to mechanical tolerances in the SEM and magnetic inhomogeneity, neither the electric field nor the magnetic field always share the same axis of symmetry. Therefore, each of the two fields deflects the primary electron beam independently.It therefore happens that, despite the described procedure, a good image with a desired resolution and contrast cannot be achieved because the primary electron beam does not run along a desired axis of symmetry of the first electric field or along a desired axis of symmetry of the magnetic field.

[0013] When an objective lens in the form of an electrostatic circular lens is perfectly manufactured, it possesses an axis of symmetry, namely the axis of rotation. An electron in a primary particle beam moves along this axis of symmetry without being deflected. However, manufacturing a perfectly crafted electrostatic circular lens is difficult. Often, electrostatic circular lenses are not manufactured perfectly. Therefore, what is referred to as the axis of symmetry of these electrostatic circular lenses is often only a desired, ideal axis of symmetry that does not actually exist in the manufactured electrostatic circular lenses. In the case of a magnetic circular lens, inhomogeneities in the magnetic material typically cause the magnetic field to be non-symmetrical about the desired, ideal axis of symmetry.The following is achieved during wobbling: If an electron of the primary electron beam is located at an initial point in the region between the objective lens and the electron source, the direction in which the electron enters the objective lens can be adjusted using the aperture diaphragm and the electrostatic and / or magnetic deflection units. If the displacement caused by the entire objective lens and integrated at the object is zero, the objective lens current can be wobbled without changing the electron's landing point on the object in a linear and quasi-static approximation. In practice, however, slight changes around the landing point occur.

[0014] Regarding the state of the art, reference is also made to US 2002 / 0179851 A1, US 2005 / 0006598 A1, US 2012 / 0138793 A1 and US 6 067 164 A.

[0015] The invention is based on the objective of providing a method for imaging an object with a particle beam device and a particle beam device for carrying out the method, in which an image with good resolution and with a desired contrast can be achieved.

[0016] According to the invention, this problem is solved by a method for operating a particle beam device with the features of claim 1. Furthermore, the invention relates to a computer program product with the features of claim 8. A particle beam device according to the invention for imaging and / or processing an object is defined by the features of claim 9. Further features of the invention will become apparent from the following description, the appended claims, and / or the accompanying figures.

[0017] The invention relates to a method for operating a particle beam device. The particle beam device is designed, for example, for imaging, analyzing, and / or processing an object. In particular, the particle beam device is designed as an electron beam device and / or as an ion beam device. For example, the particle beam device is provided to have a beam generator for producing a particle beam with charged primary particles. For example, the primary particles are electrons or ions. Furthermore, the particle beam device has, for example, an objective lens with at least one terminal electrode. The terminal electrode is arranged, for example, opposite the object in the particle beam device. The objective lens generates, on the one hand, a magnetic field and, on the other hand, an electric field between the terminal electrode and the object. The objective lens serves to focus the particle beam onto the object.When the particle beam interacts with the object, interaction particles and / or interaction radiation are produced. The interaction particles are, for example, secondary particles, especially secondary electrons, and / or backscattered particles, such as backscattered electrons. The interaction radiation is, for example, X-rays or cathodoluminescence. The particle beam instrument also includes, for example, a movable sample stage for positioning the object within the instrument. The sample stage is designed to be movable so that the object can be positioned within the particle beam instrument. For example, the sample stage is located in a sample chamber of the particle beam instrument. The sample stage is designed to be movable in, for example, three mutually perpendicular directions.Additionally, the sample stage can be rotated about two mutually perpendicular axes, namely a first axis and a second axis. Furthermore, the particle beam device according to the invention comprises, for example, at least one detector for detecting the interaction particles and / or interaction radiation and for generating detector signals. The particle beam device also includes, for example, at least one display device for displaying an image of the object, wherein the image is generated by means of the detector signals. In addition, the particle beam device includes a control unit for setting a beam parameter.

[0018] Examples of the beam parameter are given below.

[0019] In the method according to the invention, reference images are acquired in a reference position of the sample stage. Specifically, a first reference image of the object is acquired in the reference position of the sample stage with a beam parameter that has a reference value. For example, the reference value is a zero value or a zero point. Furthermore, a second reference image of the object is acquired in the reference position of the sample stage with a beam parameter that has a value different from the reference value. Subsequently, the image shift of the second reference image relative to the first reference image is calculated. In particular, it is provided that the image shift is calculated using cross-correlation.

[0020] Furthermore, in the method according to the invention, images of the object are acquired in a first position of the sample stage. For this purpose, it is particularly provided that a first image of the object in the first position of the sample stage is acquired with the beam parameter that has the reference value. A second image of the object in the first position of the sample stage is then acquired with the beam parameter that has a value different from the reference value. Subsequently, an image shift of the first image relative to the first reference image and an image shift of the second image relative to the first reference image are calculated. The calculation is performed, for example, by means of cross-correlation.

[0021] Furthermore, images of the object are acquired in a second position on the sample stage. For example, a third image of the object in this second position is acquired using a beam parameter that corresponds to the reference value. A fourth image of the object in this second position is then acquired using a beam parameter that differs from the reference value. Finally, the image shift of the third image relative to the first reference image is calculated, as is the image shift of the fourth image relative to the first reference image. This image shift is calculated, for example, using cross-correlation.

[0022] Basically, in the above-mentioned process steps, images of the object are taken in different positions of the sample table, firstly at a reference value of the beam parameter and secondly at a beam parameter value that is different from the reference value.

[0023] The method according to the invention involves interpolating the image shifts of the first and third images, each acquired at the reference value, relative to the first reference image, depending on the position of the sample stage. Furthermore, the image shifts of the second, second, and fourth reference images, each acquired at a beam parameter value different from the reference value, are interpolated relative to the first reference image, again depending on the position of the sample stage. Finally, a target position of the sample stage is determined at which the interpolated image shifts are identical at both the reference value and the beam parameter value. Subsequently, the particle beam instrument is operated with the beam parameter corresponding to the reference value, with the sample stage positioned at the target position.

[0024] In one embodiment of the method according to the invention, the method comprises at least one of the following steps: - Setting the beam parameter to the reference value; - Setting the beam parameter to a value that differs from the reference value; - Setting the reference position of the sample table by rotating the sample table around the first axis and / or around the second axis; - Setting the first position of the sample table by rotating the sample table around the first axis and / or around the second axis; - Setting the second position of the sample table by rotating the sample table around the first axis and / or around the second axis.

[0025] In a further embodiment of the method according to the invention, it is additionally or alternatively provided that the control unit is a radiation generator control unit for supplying the radiation generator with an operating voltage and for adjusting the operating voltage, and that the radiation parameter is the operating voltage. For example, the operating voltage is a cathode voltage.

[0026] If an image displacement is detected at a new position of the sample stage, and thus at a new position of the object, the following steps are performed at this new position: Another image of the object is acquired with the beam parameter corresponding to the reference value. Furthermore, yet another image of the object is acquired with the beam parameter differing from the reference value. Subsequently, the image shift of this second image relative to the first reference image, and the image shift of the third image relative to the first reference image, are calculated. This calculation is performed, for example, using cross-correlation. Finally, the image shift of this second image relative to the first reference image is interpolated as a function of the new position of the sample stage, taking into account the interpolation already performed.Furthermore, the image shift of the subsequent image relative to the first reference image is interpolated based on the new position of the sample stage, taking into account the interpolation already performed above. A further target position of the sample stage is then determined, at which the interpolated image shifts are identical for both the reference value and the beam parameter value. The particle beam instrument is then operated with the beam parameter corresponding to the reference value and with the new target position of the sample stage.

[0027] The invention also relates to a computer program product comprising a program code that can be loaded into, or is loaded into, a processor of a particle beam device and which, when implemented, controls a particle beam device in such a way that a method with at least one of the preceding or following features or with a combination of at least two of the preceding or following features is carried out.

[0028] The invention also relates to a particle beam device for imaging, analyzing, and / or processing an object. In particular, the particle beam device is designed as an electron beam device and / or as an ion beam device. For example, the particle beam device is provided to have a beam generator for producing a particle beam with charged primary particles. For example, the primary particles are electrons or ions. Furthermore, the particle beam device according to the invention has an objective lens with at least one terminal electrode. The terminal electrode is, for example, arranged opposite the object in the particle beam device. The objective lens generates, on the one hand, a magnetic field and, on the other hand, an electric field between the terminal electrode and the object. The objective lens serves to focus the particle beam onto the object.When the particle beam interacts with the object, interaction particles and / or interaction radiation are produced. The interaction particles are, for example, secondary particles, especially secondary electrons, and / or backscattered particles, such as backscattered electrons. The interaction radiation is, for example, X-rays or cathodoluminescence. The particle beam device has at least one adjustable deflection unit for deflecting the particle beam. Additionally or alternatively, the particle beam device has an adjustable aperture unit for shaping the particle beam. In other words, the aperture unit selects a partial beam with a suitable direction from a large bundle of the particle beam. In particular, it is provided that a single unit is designed as both a deflection unit and an aperture unit.The deflection unit comprises, for example, electrostatic deflection units and / or magnetic deflection units. The aperture unit is designed, for example, as a mechanically movable aperture unit. For example, the particle beam device has a movable sample stage for arranging the object within the particle beam device. The sample stage is designed to be movable such that the object can be positioned within the particle beam device. For example, the sample stage is arranged in a sample chamber of the particle beam device. The sample stage is designed to be movable, for example, in three mutually perpendicular directions. In addition, the sample stage can be rotated about two mutually perpendicular axes. Furthermore, the particle beam device according to the invention has at least one detector for detecting the interaction particles and / or interaction radiation and for generating detector signals.The particle beam device according to the invention further comprises at least one display unit for displaying an image of the object, wherein the image of the object is based on the detector signals. The particle beam device also includes, for example, at least one objective lens control unit for supplying the objective lens with an objective lens current and for adjusting the objective lens current. Furthermore, the particle beam device according to the invention additionally or alternatively includes at least one beam generator control unit for supplying the beam generator with an operating voltage and for adjusting the operating voltage. The operating voltage is, for example, a cathode voltage. Furthermore, the particle beam device according to the invention additionally or alternatively includes at least one terminal electrode control unit for supplying the terminal electrode with a terminal electrode voltage and for adjusting the terminal electrode voltage.Furthermore, the particle beam device according to the invention is provided with a processor in which a computer program product is loaded, which has one of the features mentioned above or below, or a combination of at least two of the features mentioned above or below.

[0029] In one embodiment of the particle beam device according to the invention, it is additionally or alternatively provided that the particle beam device has an object voltage control unit for supplying the object with an object voltage.

[0030] In a further embodiment of the particle beam device according to the invention, it is additionally or alternatively provided that the particle beam device has at least one corrector for correcting chromatic and / or spherical aberration. For example, the corrector is designed as a mirror corrector.

[0031] As mentioned above, in a further embodiment of the particle beam device according to the invention, it is additionally or alternatively provided that the particle beam device is designed as an electron beam device and / or as an ion beam device.

[0032] In a further embodiment of the particle beam device according to the invention, it is additionally or alternatively provided that the beam generator for generating a particle beam with charged primary particles is designed as a first beam generator for generating a first particle beam with first charged primary particles, and the objective lens is designed as a first objective lens for focusing the first particle beam onto the object. Furthermore, the particle beam device has at least one second beam generator for generating a second particle beam with second charged primary particles and at least one second objective lens for focusing the second particle beam onto the object. The second charged primary particles are, for example, electrons or ions.

[0033] The invention is described in more detail below with reference to exemplary embodiments and drawings. These drawings show... Fig. 1 a schematic representation of a first embodiment of a particle beam device; Fig. 2 a schematic representation of a second embodiment of a particle beam device; Fig. 3 a schematic representation of a third embodiment of a particle beam device; Fig. 4 a schematic representation of a fourth embodiment of a particle beam device; Fig. 5 a schematic representation of an exemplary embodiment of a sample table; Fig. 6 another schematic representation of the sample table according to Fig. 5; Fig. 7 a schematic representation of an exemplary embodiment of an objective lens; Fig. 8 a schematic representation of another embodiment of an objective lens; Fig. 9 a schematic representation of a flowchart of a process; Fig. 10 a schematic representation of a periodic change of an objective lens current; Fig. 11 a schematic representation of a periodic change in the operating voltage of a particle beam device; Fig. 12 a schematic representation of the sequence of a further procedure; Fig. 13 a schematic representation of the sequence of a further procedure; as well as Fig. 14A / B a schematic representation of a process according to the invention.

[0034] The invention will now be explained in more detail using particle beam devices in the form of a SEM and in the form of a combination device comprising an electron beam column and an ion beam column. It is expressly pointed out that the invention can be used with any particle beam device, in particular with any electron beam device and / or any ion beam device.

[0035] Fig. Figure 1 shows a schematic representation of a SEM 100. The SEM 100 comprises a first emitter with an electron source 101, which is configured as a cathode. Furthermore, the first emitter includes a suppressor electrode 101A and an extraction electrode 102. The SEM 100 is also provided with an anode 103, which is mounted on one end of a beamline 104 of the SEM 100. For example, the electron source 101 is configured as a thermal field emitter. However, the invention is not limited to such an electron source 101. Rather, any electron source can be used.

[0036] Electrons emitted from electron source 101 form a primary electron beam. Due to a potential difference between electron source 101 and anode 103, the electrons are accelerated to a predefinable kinetic energy relative to a predefinable potential. In the embodiment shown here, the potential is 1 kV to 20 kV relative to the ground potential of a sample chamber housing 120, for example 5 kV to 15 kV, and in particular 8 kV. Alternatively, it could also be at ground potential.

[0037] Two condenser lenses are arranged on the beamline tube 104: a first condenser lens 105 and a second condenser lens 106. Looking from the electron source 101 towards an objective lens 107, the first condenser lens 105 and then the second condenser lens 106 are arranged. It is explicitly noted that other embodiments of the SEM 100 may have only a single condenser lens. A first aperture unit 108 is arranged between the anode 103 and the first condenser lens 105. The first aperture unit 108, together with the anode 103 and the beamline tube 104, is at a high-voltage potential, namely the potential of the anode 103 or at ground. The first aperture unit 108 has numerous first aperture openings 108A, one of which is located in Fig. Figure 1 is shown. For example, two first aperture openings 108A are present. Each of the numerous first aperture openings 108A has a different opening diameter. By means of an adjustment mechanism (not shown), it is possible to set a desired first aperture opening 108A on an optical axis OA of the SEM 100. It is explicitly pointed out that in further embodiments, the first aperture unit 108 may only be provided with a single aperture opening 108A. In this embodiment, an adjustment mechanism cannot be provided. The first aperture unit 108 is then fixed in position.

[0038] A second aperture unit 109 is arranged between the first condenser lens 105 and the second condenser lens 106. A first deflection unit 131 is arranged on a first side of the second aperture unit 109, facing the electron source 101. Furthermore, a second deflection unit 132 is arranged on a second side of the second aperture unit 109, facing the second condenser lens 106. For example, both the first deflection unit 131 and the second deflection unit 132 have electrostatic and / or magnetic units that are adjustable via a control variable. If the second aperture unit 109 is a movable single- or multi-hole aperture, for example, at least one of the two deflection units 131 and 132 is used. If the second aperture unit 109 is a fixed single aperture, then at least two deflection units are used, for example, the first deflection unit 131 and the second deflection unit 132.If the second aperture 109 is a fixed multi-hole aperture, then, for example, three deflection units are used (not shown).

[0039] If the second aperture unit 109 is designed to be movable, it shapes the primary particle beam through the geometric shape of an aperture opening in the second aperture unit 109. The second aperture unit 109 selects a sub-bundle of the primary particle beam and thus aligns the primary particle beam. This allows the second aperture unit 109 to tilt the primary particle beam, but only about a virtual position of the electron source 101. Therefore, the function of the movable second aperture unit 109 can be described as shaping and aligning the primary particle beam. In the case of a combination of a stationary second aperture unit 109 and a deflection unit, the function can be described analogously as shaping and deflecting the primary particle beam.

[0040] The objective lens 107 has pole shoes 110 in which a bore is formed. The beam guide tube 104 is guided through this bore. A coil 111 is also arranged in the pole shoes 110.

[0041] An electrostatic deceleration device is arranged in a lower section of the beam guide tube 104. This device comprises a single electrode 112 in the form of a terminal electrode and a tubular electrode 113. The single electrode 112 is positioned opposite an object 114. The tubular electrode 113 is located at the end of the beam guide tube 104 that faces the object 114. The tubular electrode 113, together with the beam guide tube 104, is at the potential of the anode 103, while the single electrode 112 and the object 114 are at a potential lower than that of the anode 103. In this case, this is the ground potential of the housing of the sample chamber 120. In this way, the electrons of the primary electron beam can be decelerated to a desired energy required for the examination of the object 114.

[0042] An initial electric field exists between the tubular electrode 113 and the individual electrode 112. If the individual electrode 112 and the object 114 are at different potentials (in Fig. (1 not shown), a second electric field exists between the single electrode 112 and the object 114.

[0043] The SEM 100 also features a scanning device 115, by which the primary electron beam can be deflected and scanned across the object 114. The electrons of the primary electron beam interact with the object 114. As a result of this interaction, interaction particles are produced, which are then detected. In particular, electrons are emitted from the surface of the object 114 – so-called secondary electrons – or electrons from the primary electron beam are backscattered – so-called backscattered electrons.

[0044] Object 114 and the single electrode 112 can also be at different potentials, deviating from ground, as mentioned above. This makes it possible to adjust the location of the delay of the primary electron beam relative to object 114. For example, if the delay is performed quite close to object 114, imaging errors are reduced.

[0045] For the detection of secondary electrons and / or backscattered electrons, a detector array comprising a first detector 116 and a second detector 117 is arranged in the beamline 104. The first detector 116 is arranged along the optical axis OA on the source side, while the second detector 117 is arranged along the optical axis OA on the object side within the beamline 104. The first detector 116 and the second detector 117 are offset from each other in the direction of the optical axis OA of the SEM 100. Both the first detector 116 and the second detector 117 each have a through-hole through which the primary electron beam can pass. The first detector 116 and the second detector 117 are approximately at the potential of the anode 103 and the beamline 104, respectively. The optical axis OA of the SEM 100 passes through the respective through-holes.

[0046] The second detector 117 is primarily used for the detection of secondary electrons. Upon exiting object 114, the secondary electrons initially possess low kinetic energy and move in arbitrary directions. The strong suction field emanating from the tubular electrode 113 accelerates the secondary electrons towards the objective lens 107. The secondary electrons enter the objective lens 107 in an approximately parallel direction. The beam diameter of the secondary electrons remains small even within the objective lens 107. The objective lens 107 exerts a strong effect on the secondary electrons, creating a comparatively short focus with sufficiently steep angles to the optical axis OA, such that the secondary electrons diverge considerably after passing through the focus and strike the second detector 117 on its active surface.Electrons backscattered by object 114—that is, backscattered electrons which, compared to the secondary electrons, have a relatively high kinetic energy upon exiting object 114—are only detected to a small extent by the second detector 117. The high kinetic energy and the angles of the backscattered electrons to the optical axis OA upon exiting object 114 result in a beam waist, i.e., a beam region with a minimum diameter, of backscattered electrons located near the second detector 117. A large proportion of the backscattered electrons pass through the aperture of the second detector 117. The first detector 116 therefore serves primarily to detect the backscattered electrons.

[0047] In a further embodiment of the SEM 100, the first detector 116 can additionally be equipped with a retarding grid 116A. The retarding grid 116A is arranged on the side of the first detector 116 facing the object 114. The retarding grid 116A has a negative potential with respect to the potential of the beam guide tube 104, such that only backscattered electrons with high energy pass through the retarding grid 116A to the first detector 116. Additionally or alternatively, the second detector 117 has another retarding grid, which is configured analogously to the aforementioned retarding grid 116A of the first detector 116 and has an analogous function.

[0048] The detector signals generated by the first detector 116 and the second detector 117 are used to generate an image or images of the surface of object 114.

[0049] It is explicitly noted that the apertures of the first aperture unit 108 and the second aperture unit 109, as well as the through-holes of the first detector 116 and the second detector 117, are exaggerated. The through-holes of the first detector 116 and the second detector 117 have a perpendicular dimension OA ranging from 0.5 mm to 5 mm. For example, they are circular and have a diameter ranging from 1 mm to 3 mm perpendicular to the optical axis OA.

[0050] In the embodiment shown here, the second aperture unit 109 is designed as a pinhole aperture and is provided with a second aperture opening 118 for the passage of the primary electron beam, which has a diameter in the range of 5 µm to 500 µm, for example 35 µm. Alternatively, in another embodiment, the second aperture unit 109 is provided with several aperture openings that can be mechanically moved relative to the primary electron beam or that can be reached by the primary electron beam using electrical and / or magnetic deflection elements. Reference is also made to the above descriptions regarding the second aperture unit 109. The second aperture unit 109 is designed as a pressure-stage aperture. This separates a first region in which the electron source 101 is arranged and in which an ultra-high vacuum prevails (10 -7 hPa up to 10-12 hPa), from a second area which has a high vacuum (10 -3 hPa up to 10 -7 hPa). The second area is the intermediate pressure area of ​​the jet guide tube 104, which leads to the sample chamber 120.

[0051] Sample chamber 120 is under vacuum. A pump (not shown) is arranged on sample chamber 120 to generate the vacuum. In the Fig. In the embodiment shown in Figure 1, the sample chamber 120 is operated in a first pressure range or in a second pressure range. The first pressure range includes only pressures less than or equal to 10 -3 hPa, and the second pressure range only includes pressures greater than 10 -3 hPa. To ensure these pressure ranges, the sample chamber 120 is vacuum-sealed.

[0052] The object 114 is arranged on a sample table 122. The sample table 122 is movable in three mutually perpendicular directions, namely in an x-direction, a y-direction, and a z-direction. In addition, the sample table 122 can be rotated about two mutually perpendicular axes of rotation.

[0053] The SEM 100 also features a third detector 121, which is located in the sample chamber 120. More precisely, the third detector 121 is positioned behind the object 114 along the optical axis OA, as seen from the electron source 101. The primary electron beam passes through the object 114 under investigation. As the primary electron beam passes through the object 114, the electrons interact with the material of the object 114. The electrons passing through the object 114 are detected by the third detector 121.

[0054] The SEM 100 also has a fourth detector, namely a chamber detector 134, which is arranged in the sample chamber 120.

[0055] The first detector 116, the second detector 117, the third detector 121, and the chamber detector 134 are connected to a control unit 123, which includes a monitor 124. The control unit 123 processes detector signals generated by the first detector 116, the second detector 117, the third detector 121, and the chamber detector 134 and displays them as images on the monitor 124. Furthermore, the control unit 123 includes a processor 130 in which a computer program product with program code is loaded. This program code controls the SEM 100 in such a way that the method according to the invention is executed. This will be explained in more detail below.

[0056] The coil 111 of the objective lens 107 is connected to an objective lens control unit 125. The objective lens control unit 125 adjusts the current supplied to the coil 111. This makes it possible to influence and adjust the magnetic field generated by the objective lens 107. In one embodiment, the coil 111 can have two sub-coils. Each sub-coil has its own power supply in the objective lens control unit 125. This allows, for example, a variable magnetic field to be achieved with constant power dissipation in the sub-coils.

[0057] The radiation source is connected via a wiring system to a radiation source control unit in the form of an electron source control unit 126. The electron source 101, the suppressor electrode 101A, and the extraction electrode 102 are connected to the electron source control unit 126 and are supplied with voltage by the electron source control unit 126.

[0058] The first deflection unit 131 and the second deflection unit 132 are connected to a deflection control unit 133 and are supplied with voltages and / or currents by the deflection control unit 133.

[0059] Fig. Figure 2 shows a schematic representation of another SEM 100A. The SEM 100A according to the Fig. 2 is based on the SEM 100 according to the Fig. 1. Identical components are marked with the same reference numerals. Therefore, reference is made to the explanations given above. In contrast to the exemplary embodiment of the Fig. 1 shows the embodiment of the Fig. However, the SEM 100A also includes an object voltage control unit 127 for supplying object 114 with object voltage. The object voltage supplied to object 114 is set using the object voltage control unit 127. Furthermore, the SEM 100A additionally or alternatively has a termination electrode control unit 128, which also supplies the individual electrode 112 with a termination electrode voltage. The termination electrode control unit 128 sets the termination electrode voltage supplied to the individual electrode 112.

[0060] Fig. Figure 3 shows a particle beam device in the form of a combination device 200. The combination device 200 has two particle beam columns. Firstly, the combination device 200 is equipped with the SEM 100. Fig. 1 or with the SEM 100A of the Fig. 2, but without the sample chamber 120. Instead, the SEM 100 or the SEM 100A is arranged on a sample chamber 201. The sample chamber 201 is under vacuum. A pump (not shown) is arranged on the sample chamber 201 to generate the vacuum. In the Fig. In the embodiment shown in section 3, the sample chamber 201 is operated in a first pressure range or in a second pressure range. The first pressure range includes only pressures less than or equal to 10 -3 hPa, and the second pressure range only includes pressures greater than 10 -3 hPa. To ensure these pressure ranges, sample chamber 201 is vacuum-sealed.

[0061] The SEM 100 or the SEM 100A serves to generate a first particle beam, namely the primary electron beam described above. The SEM 100 and the SEM 100A are, with regard to the Fig. 1 and Fig. Section 2 has been explained in detail. Reference is made to these explanations. These also apply to the exemplary embodiment of the Fig. 3. Components that are not in Fig. The three shown are in the Fig. 1 and Fig. 2 shown. In addition to the SEM 100 or the SEM 100A, the combination device 200 is equipped with an ion beam device 300, which is also arranged on the sample chamber 201.

[0062] The SEM 100 or the SEM 100A is arranged vertically with respect to the sample chamber 201. In contrast, the ion beam device 300 is arranged at an angle of approximately 50° to the SEM 100 or the SEM 100A. It has a second beam generator in the form of an ion beam generator 301. Ions are generated by the ion beam generator 301, forming a second particle beam in the form of an ion beam. The ions are accelerated by means of an extraction electrode 302, which is at a predetermined potential. The second particle beam then passes through an ion optic of the ion beam device 300, the ion optic comprising a condenser lens 303 and a further objective lens 304. The further objective lens 304 ultimately creates an ion probe that is focused onto the object 114 arranged on a sample stage 122.

[0063] Above the further objective lens 304 (i.e., in the direction of the ion beam generator 301) are arranged an adjustable aperture 306, a first electrode arrangement 307, and a second electrode arrangement 308, wherein the first electrode arrangement 307 and the second electrode arrangement 308 are designed as scanning electrodes. The second particle beam is scanned across the surface of the object 114 by means of the first electrode arrangement 307 and the second electrode arrangement 308, with the first electrode arrangement 307 acting in a first direction and the second electrode arrangement 308 in a second direction opposite to the first. Thus, scanning is performed, for example, in an x-direction. Scanning in a perpendicular y-direction is achieved by further electrodes (not shown) rotated by 90° on the first electrode arrangement 307 and on the second electrode arrangement 308.

[0064] As explained above, object 114 is positioned on sample table 122. Also in the case of the Fig. In the embodiment shown in Figure 3, the sample table 122 is designed to be movable in three mutually perpendicular directions, namely in an x-direction, a y-direction, and a z-direction. Furthermore, the sample table 122 can be rotated about two mutually perpendicular axes of rotation.

[0065] The one in Fig. The distances shown between the individual units of the combination device 200 are exaggerated in order to better illustrate the individual units of the combination device 200.

[0066] As explained above, the SEM 100 or the SEM 100A has a control unit 123 equipped with a monitor 124. The control unit 123 processes detector signals generated by the first detector 116, the second detector 117, the third detector 121, and the chamber detector 134 and displays them as images on the monitor 124. Furthermore, the control unit 123 has a processor 130 in which a computer program product with program code is loaded, which controls the SEM 100 or the SEM 100A such that the method according to the invention is carried out. This will be explained in more detail below.

[0067] The coil 111 of the objective lens 107 of the SEM 100 or SEM 100A is connected to the objective lens control unit 125. The objective lens control unit 125 adjusts the objective lens current supplied to the coil 111. This makes it possible to influence and adjust a magnetic field generated by the objective lens 107.

[0068] Furthermore, a first electric field exists between the tubular electrode 113 and the individual electrode 112. In contrast, a second electric field exists between the individual electrode 112 and the object 114.

[0069] The radiation source of the SEM 100 or SEM 100A is connected to the radiation source control unit, which is the electron source control unit 126, via a wiring connection. The electron source 101, the suppressor electrode 101A, and the extraction electrode 102 are connected to the electron source control unit 126 and are supplied with voltage and / or current by the electron source control unit 126.

[0070] If, in the exemplary embodiment, the Fig. 3. If the SEM 100A is used, then the SEM 100A has the object voltage control unit 127 for supplying object 114 with object voltage. The object voltage supplied to object 114 is set by means of the object voltage control unit 127. In addition, or alternatively, the SEM 100A has the termination electrode control unit 128, which supplies the individual electrode 112 with the termination electrode voltage. The termination electrode control unit 128 is used to set the termination electrode voltage supplied to the individual electrode 112.

[0071] Here too, the first deflection unit 131 and the second deflection unit 132 are connected to a deflection control unit 133 via a line and are supplied with voltages and / or currents by the deflection control unit 133.

[0072] Fig. Figure 4 is a schematic representation of another embodiment of a particle beam device according to the invention. This embodiment of the particle beam device is designated by reference numeral 400 and includes a mirror corrector for correcting, for example, chromatic and / or spherical aberration. The particle beam device 400 comprises a particle beam column 401, which is designed as an electron beam column and essentially corresponds to an electron beam column of a corrected SEM. However, the particle beam device 400 is not limited to an SEM with a mirror corrector. Rather, the particle beam device can include any type of corrector unit.

[0073] The particle beam column 401 comprises a particle beam generator in the form of an electron source 402 (cathode), a suppressor electrode 402A, an extraction electrode 403, and an anode 404. For example, the electron source 402 is configured as a thermal field emitter. Electrons emitted from the electron source 402 are accelerated towards the anode 404 due to a potential difference between the electron source 402 and the anode 404. Thus, a particle beam in the form of an electron beam is generated along a first optical axis OA1.

[0074] The particle beam is guided along a beam path corresponding to the first optical axis OA1 after it exits the electron source 402. A first electrostatic lens 405, a second electrostatic lens 406, and a third electrostatic lens 407 are used to guide the particle beam.

[0075] Furthermore, the particle beam is aligned along the beam path using a beam guidance device. The beam guidance device of this embodiment comprises a source alignment unit with two magnetic deflection units 408 arranged along the first optical axis OA1. In addition, the particle beam device 400 includes electrostatic beam deflection units. A first electrostatic beam deflection unit 409, which in another embodiment is also configured as a quadrupole, is arranged between the second electrostatic lens 406 and the third electrostatic lens 407. The first electrostatic beam deflection unit 409 is also arranged downstream of the magnetic deflection units 408. A first multipole unit 409A, in the form of a first magnetic deflection unit, is arranged on one side of the first electrostatic beam deflection unit 409.Furthermore, a second multipole unit 409B, in the form of a second magnetic deflection unit, is arranged on the other side of the first electrostatic beam deflection unit 409. The first electrostatic beam deflection unit 409, the first multipole unit 409A, and the second multipole unit 409B are adjusted to align the particle beam with respect to the axis of the third electrostatic lens 407 and the inlet window of a beam deflection device 410. The first electrostatic beam deflection unit 409, the first multipole unit 409A, and the second multipole unit 409B can act together like a Wien filter. Another magnetic deflection element 432 is arranged at the inlet of the beam deflection device 410.

[0076] The beam deflection device 410 is used as a particle beam deflector, which deflects the particle beam in a specific manner. The beam deflection device 410 comprises several magnetic sectors, namely a first magnetic sector 411A, a second magnetic sector 411B, a third magnetic sector 411C, a fourth magnetic sector 411D, a fifth magnetic sector 411E, a sixth magnetic sector 411F, and a seventh magnetic sector 411G. The particle beam enters the beam deflection device 410 along the first optical axis OA1 and is deflected by the beam deflection device 410 in the direction of a second optical axis OA2. The beam deflection is achieved by the first magnetic sector 411A, the second magnetic sector 411B, and the third magnetic sector 411C by an angle of 30° to 120°.The second optical axis OA2 is aligned at the same angle to the first optical axis OA1. The beam deflection device 410 also deflects the particle beam, which is guided along the second optical axis OA2, in the direction of a third optical axis OA3. The beam deflection is provided by the third magnetic sector 411C, the fourth magnetic sector 411D, and the fifth magnetic sector 411E. In the embodiment shown in . Fig. 4. The deflection to the second optical axis OA2 and to the third optical axis OA3 is provided by deflecting the particle beam at an angle of 90°. Thus, the third optical axis OA3 is coaxial with the first optical axis OA1. However, it should be noted that the particle beam device 400 according to the invention described herein is not limited to deflection angles of 90°. Rather, any suitable deflection angle can be selected by the beam deflection device 410, for example, 70° or 110°, so that the first optical axis OA1 is not coaxial with the third optical axis OA3. For further details of the beam deflection device 410, reference is made to WO 2002 / 067286 A2.

[0077] After the particle beam is deflected by the first magnetic sector 411A, the second magnetic sector 411B, and the third magnetic sector 411C, the particle beam is guided along the second optical axis OA2. The particle beam is guided to an electrostatic mirror 414 and, on its way to the electrostatic mirror 414, passes by a fourth electrostatic lens 415, a third multipole unit 416A in the form of a magnetic deflection unit, a second electrostatic beam deflection unit 416, a third electrostatic beam deflection unit 417, and a fourth multipole unit 416B in the form of a magnetic deflection unit. The electrostatic mirror 414 comprises a first mirror electrode 413A, a second mirror electrode 413B, and a third mirror electrode 413C.Electrons from the particle beam, which are reflected back at the electrostatic mirror 414, travel again along the second optical axis OA2 and re-enter the beam deflection device 410. They are then deflected by the third magnetic sector 411C, the fourth magnetic sector 411D and the fifth magnetic sector 411E to the third optical axis OA3.

[0078] The electrons of the particle beam exit the beam deflection device 410 and are guided along the third optical axis OA3 to the object 425 to be examined. On its way to the object 425, the particle beam passes through a fifth electrostatic lens 418, a beam guide tube 420, a fifth multipole unit 418A, a sixth multipole unit 418B, and an objective lens 421. The fifth electrostatic lens 418 is an electrostatic immersion lens. The particle beam is decelerated or accelerated by the fifth electrostatic lens 418 to an electrical potential of the beam guide tube 420.

[0079] The particle beam is focused by the objective lens 421 into a focal plane in which the object 425 is located. The object 425 is arranged on a movable sample stage 424. The movable sample stage 424 is located in a sample chamber 426 of the particle beam instrument 400. The sample stage 424 is movable in three mutually perpendicular directions, namely in an x-direction, a y-direction, and a z-direction. In addition, the sample stage 424 can be rotated about two mutually perpendicular axes of rotation. The sample chamber 426 is under vacuum. A pump (not shown) is arranged on the sample chamber 426 to generate the vacuum. Fig. In the embodiment shown in Figure 4, the sample chamber 426 is operated in a first pressure range or in a second pressure range. The first pressure range includes only pressures less than or equal to 10 -3hPa, and the second pressure range only includes pressures greater than 10 -3 hPa. To ensure these pressure ranges, sample chamber 426 is vacuum-sealed.

[0080] The objective lens 421 can be configured as a combination of a magnetic lens 422 and a sixth electrostatic lens 423 in the form of a terminal electrode. The end of the beam guide tube 420 can also be an electrode of an electrostatic lens. Particles from the particle beam device 400 are decelerated—after exiting the beam guide tube 420—to a potential of the object 425, which is located on the sample stage 424. The objective lens 421 is not limited to a combination of the magnetic lens 422 and the sixth electrostatic lens 423. Rather, the objective lens 421 can assume any suitable form. For example, the objective lens 421 can also be configured as a purely magnetic lens or as a purely electrostatic lens.

[0081] The particle beam, focused onto object 425, interacts with it, generating interaction particles. Specifically, secondary electrons are emitted from object 425, or backscattered electrons are scattered by object 425. The secondary electrons or backscattered electrons are then accelerated and guided into the beam guide tube 420 along the third optical axis OA3. The paths of the secondary electrons and backscattered electrons, in particular, run in the opposite direction to the particle beam.

[0082] The particle beam device 400 comprises a first analysis detector 419, which is arranged along the beam path between the beam deflection device 410 and the objective lens 421. Secondary electrons traveling in directions oriented at a large angle to the third optical axis OA3 are detected by the first analysis detector 419. Backscattered electrons and secondary electrons that have a small axial distance to the third optical axis OA3 at the location of the first analysis detector 419—i.e., backscattered electrons and secondary electrons that are a small distance from the third optical axis OA3 at the location of the first analysis detector 419—enter the beam deflection device 410 and are deflected by the fifth magnetic sector 411E, the sixth magnetic sector 411F, and the seventh magnetic sector 411G along a detection beam path 427 to a second analysis detector 428.The deflection angle is, for example, 90° or 110°.

[0083] The first analysis detector 419 generates detector signals, largely produced by emitted secondary electrons. These detector signals are fed to a control unit 123 and used to obtain information about the properties of the interaction area of ​​the focused particle beam with the object 425. Specifically, the focused particle beam is scanned across the object 425 using a scanning device 429. The detector signals generated by the first analysis detector 419 can then be used to create an image of the scanned area of ​​the object 425, which can be displayed on a display unit. The display unit is, for example, a monitor 124 located at the control unit 123.

[0084] The second analysis detector 428 is also connected to the control unit 123. Detector signals from the second analysis detector 428 are routed to the control unit 123 and used to generate an image of the rasterized area of ​​the object 425 and display it on a display unit. The display unit is, for example, the monitor 124, which is located at the control unit 123.

[0085] Furthermore, the control unit 123 has a processor 130 in which a computer program product with program code is loaded, which controls the particle beam device 400 in such a way that the method according to the invention is carried out. This will be explained in more detail below.

[0086] The coil of the objective lens 421 is connected to an objective lens control unit 125 via a conductor. The objective lens control unit 125 adjusts the current supplied to the coil. This makes it possible to influence and adjust the magnetic field generated by the objective lens 421.

[0087] Furthermore, a first electric field exists between the end of the beam guide tube 420 and the sixth electrostatic lens 423. In contrast, a second electric field exists between the sixth electrostatic lens 423 and the object 425.

[0088] The electron source 402, the suppressor electrode 402A and the extraction electrode 403 are connected to an electron source control unit 126 and are supplied with voltage and / or current by the electron source control unit 126.

[0089] Additionally, an object voltage control unit 127 is provided to supply object 425 with object voltage. The object voltage supplied to object 425 is set by means of the object voltage control unit 127. Furthermore, the particle beam device 400 additionally or alternatively has a termination electrode control unit 128, which supplies the sixth electrostatic lens 423, in the form of the termination electrode, with a termination electrode voltage. The termination electrode control unit 128 is used to set the termination electrode voltage supplied to the sixth electrostatic lens 423.

[0090] The following section will discuss in more detail the sample stage 122, 424 of the particle beam instruments 100, 100A, 200 and 400 described above. The sample stage 122, 424 is designed as a movable sample stage, which is located in the Fig. 5 and Fig. Figure 6 is shown schematically. It should be noted that the invention is not limited to the sample table 122, 424 described herein. Rather, the invention can include any movable sample table suitable for the invention.

[0091] The object 114, 425 is arranged on the sample table 122, 424. The sample table 122, 424 has moving elements which ensure that the sample table 122, 424 moves in such a way that an area of ​​interest on the object 114, 425 can be examined using a particle beam. The moving elements are located in the Fig. 5 and Fig. 6 are shown schematically and are explained below.

[0092] The sample stage 122, 424 has a first movement element 600 on a housing 601 of the sample chamber 120, 201 or 426 in which the sample stage 122, 424 is arranged. The first movement element 600 enables movement of the sample stage 122, 424 along the z-axis (third table axis). Furthermore, a second movement element 602 is provided. The second movement element 602 enables rotation of the sample stage 122, 424 about a first table rotation axis 603, which is also referred to as the tilt axis. This second movement element 602 serves to tilt the object 114, 425 about the first table rotation axis 603.

[0093] A third movement element 604 is arranged on the second movement element 602. This third movement element serves as a guide for a slide and ensures that the sample table 122, 424 is movable in the x-direction (first table axis). The aforementioned slide is itself a further movement element, namely a fourth movement element 605. The fourth movement element 605 is designed such that the sample table 122, 424 is movable in the y-direction (second table axis). For this purpose, the fourth movement element 605 has a guide in which another slide is guided. A holder 609 with the object 114, 425 is arranged on this slide.

[0094] The bracket 609 is in turn equipped with a fifth movement element 606, which makes it possible to rotate the bracket 609 about a second table rotation axis 607. The second table rotation axis 607 is oriented perpendicular to the first table rotation axis 603.

[0095] Due to the arrangement described above, the sample table 122, 424 of the embodiment discussed here has the following kinematic chain: first movement element 600 (movement along the z-axis) - second movement element 602 (rotation about the first table rotation axis 603) - third movement element 604 (movement along the x-axis) - fourth movement element 605 (movement along the y-axis) - fifth movement element 606 (rotation about the second table rotation axis 607).

[0096] In another (not shown) embodiment, it is provided to arrange further movement elements on the sample table 122, 424, so that movements along further translational axes and / or around further rotational axes are made possible.

[0097] As from the Fig. As can be seen in Figure 6, each of the aforementioned motion elements is connected to a stepper motor. The first motion element 600 is connected to a first stepper motor M1 and is driven by a driving force provided by the first stepper motor M1. The second motion element 602 is connected to a second stepper motor M2, which drives the second motion element 602. The third motion element 604 is in turn connected to a third stepper motor M3. The third stepper motor M3 provides a driving force to drive the third motion element 604. The fourth motion element 605 is connected to a fourth stepper motor M4, with the fourth stepper motor M4 driving the fourth motion element 605. Furthermore, the fifth motion element 606 is connected to a fifth stepper motor M5. The fifth stepper motor M5 provides a driving force that drives the fifth motion element 606.The aforementioned stepper motors M1 to M5 are controlled by a control unit 608 (see . Fig. 6).

[0098] Fig. Figure 7 shows another embodiment of an objective lens 107A. The objective lens 107A is based on the objective lens 107 according to the Fig. 1 and Fig. 2 and can, for example, be used with the SEM 100 according to the Fig. 1, where SEM 100A according to the Fig. 2 and / or in the case of the combination device 200 according to the Fig. 3. The objective lens 107A has pole shoes 110A in which a bore is formed. A beam guide tube 104A is guided through this bore. A coil 111A is also arranged in the pole shoes 110A. An electrostatic delay device is arranged in a lower region of the beam guide tube 104A. This device has a single electrode 112A in the form of a termination electrode and a tubular electrode 113A, which is arranged inside the pole shoes 110A. The single electrode 112A is arranged opposite the object 114. The tubular electrode 113A is arranged at one end of the beam guide tube 104A, which faces the object 114. The tubular electrode 113A, together with the beam guide tube 104A, is at the potential of the anode 103, while the single electrode 112A and the object 114 are at a potential lower than that of the anode 103.In this way, the electrons of the primary electron beam can be slowed down to a desired energy required for the examination of object 114.

[0099] The objective lens 107A generates a magnetic field. Additionally, two electric fields exist: a first electric field between the single electrode 112A and the tubular electrode 113A, and a second electric field between the single electrode 112A and the object 114. The single electrode 112A is aligned parallel to the tubular electrode 113A.

[0100] The coil 111A of the objective lens 107A is connected to the objective lens control unit 125. The objective lens control unit 125 adjusts the objective lens current supplied to the coil 111A. This makes it possible to influence and adjust the magnetic field generated by the objective lens 107A. Furthermore, it is possible, for example, to additionally or alternatively connect the individual electrode 112A to the termination electrode control unit 128, which supplies the individual electrode 112A with a termination electrode voltage. The termination electrode control unit 128 adjusts the termination electrode voltage supplied to the individual electrode 112A. Additionally or alternatively, it is possible to connect the object 114 to the object voltage control unit 127 to supply the object 114 with object voltage.The object voltage control unit 127 is used to set the object voltage supplied to the object 114.

[0101] Fig. Figure 8 shows a schematic representation of another embodiment of the objective lens 107A. The objective lens 107A according to the Fig. 8 is based on the objective lens 107A according to the Fig. 7. Identical components are marked with the same reference numerals. Therefore, reference is made to the explanations given above. In contrast to the exemplary embodiment of the Fig. 7 shows the embodiment of the Fig. However, an additional electrode 119A is provided, which is arranged between the tubular electrode 113A and the individual electrode 112A. In this embodiment, the individual electrode 112A is a first termination electrode, while the electrode 119A is a second termination electrode. The termination electrode control unit 128 is thus a first termination electrode control unit, to which a first termination electrode voltage is supplied to the individual electrode 112A. The first termination electrode voltage is set by means of the termination electrode control unit 128. Furthermore, it is provided to connect the electrode 119A to a second termination electrode control unit 129, which supplies the electrode 119A with a second termination electrode voltage. The second termination electrode voltage is set by means of the second termination electrode control unit 129.

[0102] Fig. Figure 9 shows an embodiment of a first method, which can be used, for example, with the SEM 100 according to the Fig. 1, with the SEM 100A according to the Fig. 2, with the combination device 200 according to the Fig. 3 and / or with the particle beam device 400 according to the Fig. 4 is carried out. The following describes the execution of the first procedure with the SEM 100 according to the Fig. 1 or with the SEM 100A according to the Fig. 2 described. The same applies to the implementation of the first procedure with the other particle beam devices mentioned above.

[0103] In the process, the objective lens current of the objective lens 107 is first swept in process steps S1 to S4. In other words, the objective lens current is first set to a current value by means of the objective lens control unit 125 (process step S1). Furthermore, the operating voltage in the form of the cathode voltage is set to a voltage value (process step S1). When the inventive process is carried out with the SEM 100A according to the Fig. 2. The termination electrode voltage(s) are also set to a termination electrode voltage value (process step S1). Then, the current value of the objective lens current is periodically changed using the objective lens control unit 125 (process step S2). This is described in the Fig. 10. The Fig. Figure 10 shows a schematic representation of the lens current I as a function of time t. The lens current I, set to the current value I1 in process step S1, is changed periodically. The period is, for example, in the range of 0.5 Hz to 3 Hz, particularly in the range of 1 Hz to 2 Hz, whereby the range limits are always included in the aforementioned ranges. The maximum amplitude is, for example, in the range of 0.1% to 10% above or below the set lens current I1, where the maximum amplitude is the distance between the peak of a maximum amplitude and the current value I1. During the periodic change of the current value I1 of the lens current, at least one property of the deflection unit and / or the aperture unit in the form of the second aperture unit 109 is adjusted in process step S3.For example, the aforementioned property is the position of the second aperture unit 109 in the SEM 100 or SEM 100A, which is set. Setting the position of the second aperture unit 109 shapes the primary particle beam. In particular, a sub-bundle of the primary particle beam is selected. Additionally or alternatively, a property of the first deflection unit 131 and / or the second deflection unit 132 is set in the form of a control variable for the electrostatic and / or magnetic units of the first deflection unit 131 or the second deflection unit 132. For example, the control variable is a voltage or a current. The setting of at least one of the aforementioned properties is such that the image of the object 114 displayed on the display device in the form of the monitor 124 either remains stationary or exhibits minimal movement of the displayed image.For example, the displacement is determined from a predefined zero point on monitor 124. In other words, at least one of the aforementioned properties is adjusted until the image of object 114 displayed on monitor 124 either remains stationary or any movement of the displayed image exhibits a minimal displacement (process step S3). Subsequently, in process step S4, the periodically changing current value is fixed to the current value from process step S1.

[0104] Furthermore, in process steps S5 to S7, the operating voltage of the radiation generator is swept. More precisely, the operating voltage is swept in the form of the cathode voltage of the electron source 101. In process step S5, the cathode voltage is periodically changed by means of the electron source control unit 126 (process step S5). This is in the Fig. 11 is described in more detail. Fig. Figure 11 shows a schematic representation of the operating voltage in the form of the cathode voltage U as a function of time t. A voltage value U1 set in process step S1 is changed periodically. The period is, for example, in the range of 0.5 Hz to 3 Hz, particularly in the range of 1 Hz to 2 Hz, whereby the range limits are always included in the aforementioned ranges. The maximum amplitude is, for example, in the range of 0.1% to 10% above or below the set operating voltage, but at least up to 100 V above or below the set operating voltage, where the maximum amplitude is the distance between the peak of a maximum amplitude and the voltage value U1. During the periodic change of the cathode voltage value U1, the sample stage 122 is moved into an aligned position of the object 114 (process step S6).The aligned position is achieved, for example, when the surface of object 114 to be imaged is aligned parallel to the single electrode 112. Moving the sample stage 122 into the aligned position of object 114 is accomplished, for example, by rotating the sample stage 122 about the first stage rotation axis 603 and / or about the second stage rotation axis 607. The sample stage 122 is moved into the aligned position such that the image of object 114 displayed on monitor 124 either remains stationary or exhibits a minimal deflection. For example, the deflection is determined from the predefined zero point on monitor 124. Subsequently, in process step S7, the periodically changing voltage value is fixed to the voltage value of process step S1.

[0105] In the first method, the magnetic field generated by the objective lens 107 is therefore taken into account. Due to the setting of the second aperture unit 109, the primary electron beam travels along a target axis of symmetry of the magnetic field. Since the primary electron beam is now guided along the target axis of symmetry and thus in a center of the magnetic field, only an asymmetry of the electric field of the objective lens 107 causes any remaining image displacement on the monitor 124 when the operating voltage is wobbled. The electric field in question is the total electric field, which is composed of the first electric field between the individual electrode 112 and the tubular electrode 113, and the second electric field between the individual electrode 112 and the object 114.By moving the sample stage 122 and thus aligning the object 114, the electric field between the individual electrode 112 and the object 114 is changed. This change neutralizes the total deflection of the primary electron beam caused by the electric fields between the tubular electrode 113 and the object 114. The aforementioned process steps S1 to S7 can be repeated several times until no or only a minimal deflection of the image on the monitor 124 occurs.

[0106] If the objective lens 107A of the SEM 100 is according to the Fig. The above also applies if 7 is used.

[0107] Another embodiment of the first method includes additional process steps S5A to S7A (see below). Fig. 12). For example, process steps S5A to S7A are performed after process step S4 according to the Fig. 9. This further embodiment of the first method is carried out, for example, with the SEM 100 of the Fig. 1 or the SEM 100A of Fig. 2 carried out, wherein the SEM 100 or the SEM 100A uses the objective lens 107A according to the Fig. 8. As mentioned above, in the objective lens 107A, the single electrode 112A is a first termination electrode, which is supplied with a first termination electrode voltage, while the electrode 119A is a second termination electrode, which is supplied with a second termination electrode voltage. In the case of the Fig. In the embodiment shown in Figure 12, the first termination electrode voltage of the individual electrode 112A and the second termination electrode voltage of electrode 119A are swept, but with different amplitudes. The first termination electrode voltage and the second termination electrode voltage have the same termination electrode voltage value AU1. The periodic change of the first termination electrode voltage now occurs with a first amplitude. A periodic change of the termination electrode voltage value AU1 of the second termination electrode voltage also occurs with a second amplitude. The first amplitude and the second amplitude are different.During the periodic changes of the first and second terminal electrode voltages, the sample stage 122 is moved by rotating it about the first stage rotation axis 603 and / or the second stage rotation axis 607 such that the image of the object 114 displayed on the monitor 124 either remains stationary or exhibits a minimal deflection (process step S6A). For example, the deflection is again determined from the predefinable zero point on the monitor 124. Subsequently, in process step S7A, the periodically changed terminal electrode voltage values ​​are fixed to the terminal electrode voltage value from process step S1.

[0108] It is specifically provided that the first and second amplitudes are controlled such that they have opposite signs. Furthermore, the magnitudes of the first and second amplitudes are different. The magnitudes of the first and second amplitudes determine the deflecting effect of the first electric field between the individual electrode 112A and the object 114, and of the second electric field between the tubular electrode 113A and the individual electrode 112A. In a further embodiment of the method, it is additionally or alternatively provided that the first amplitude is controlled to have a magnitude of zero. Additionally or alternatively, the second amplitude is controlled to have a magnitude of zero.Thus, in this embodiment of the method, either the first terminal electrode voltage is zero or the second terminal electrode voltage is zero.

[0109] If the SEM 100A of Fig. In a further embodiment of the first method, where the object voltage is used to carry out the first method according to the invention, the object voltage is applied to the object 114 by means of the object voltage control unit 127. In this further embodiment of the first method, the object voltage is also swept. In other words, the object voltage of the object 114 is set to a specific object voltage value. A periodic change of the object voltage value then occurs. The period is, for example, in the range of 0.5 Hz to 3 Hz, and particularly in the range of 1 Hz to 2 Hz, whereby the range limits are always included in the aforementioned ranges.The maximum amplitude is, for example, in the range of 0.1% to 10% above or below the set object voltage, but at least up to 100 V above or below the set object voltage, where the maximum amplitude is the distance between the peak of the amplitude and the object voltage value. During the periodic change of the object voltage value, the sample stage 122 is moved. This movement of the sample stage 122 is achieved, for example, by rotating it about the first stage rotation axis 603 and / or the second stage rotation axis 607. The movement of the sample stage 122 is such that the image of the object 114 displayed on the monitor 124 either remains stationary or exhibits a minimal displacement. For example, the displacement is determined from the predefinable zero point on the monitor 124.

[0110] Fig. Figure 13 shows an embodiment of a method which can be used, for example, with the SEM 100A according to the Fig. 2 or with the combination device 200 according to the Fig. 3 is carried out. The following describes how to perform this procedure with the SEM 100A according to the Fig. 2 described. The same applies to the implementation of this procedure with the particle beam device mentioned above.

[0111] The procedural steps S1 to S4 of the second procedure correspond to the procedural steps S1 to S4 of the procedure according to the Fig. 9. Thus, the objective lens current I of objective lens 107 is swept. Reference is made to all previously given explanations regarding process steps S1 to S4. In contrast to the embodiment according to the Fig. 9 is used in the embodiment according to the Fig. 13. In process steps S5B to S7B, the termination electrode voltage AU of the individual electrode 112 (i.e., the termination electrode) is swept. In other words, in process step S5B, a termination electrode voltage of the individual electrode 112, set to a termination electrode voltage value AU1, is periodically changed by means of the termination electrode control unit 128. The period is, for example, in the range of 0.5 Hz to 3 Hz, particularly in the range of 1 Hz to 2 Hz, whereby the range limits are always included in the aforementioned ranges. The maximum amplitude is, for example, in the range of 0.1% to 10% of the sum of the object voltage and the anode voltage, but at least up to 100 V, where the maximum amplitude is the distance between the peak of a maximum of the amplitude and the set termination electrode voltage value.During the periodic change of the terminal electrode voltage value, the sample stage 122 is moved (process step S6B). The sample stage 122 is moved into the aligned position of the object 114, for example, by rotating the sample stage 122 about the first stage rotation axis 603 and / or the second stage rotation axis 607. The sample stage 122 is moved into the aligned position such that the image of the object 114 displayed on the monitor 124 either remains stationary or exhibits a minimal displacement (process step S6B). For example, the displacement is determined from the predefined zero point on the monitor 124. Subsequently, in process step S7B, the periodically changed terminal electrode voltage value is fixed to the terminal electrode voltage value of process step S1.

[0112] In this procedure, the magnetic field generated by the objective lens 107 is taken into account in a first step. Due to the setting of the second aperture unit 109, the primary electron beam travels along a desired axis of symmetry of the magnetic field. Since the primary electron beam is now already guided along the desired axis of symmetry and thus in a center of the magnetic field, only an asymmetry of the electric field between the objective lens 107 and the object 114 causes any remaining image shift on the monitor 124 when the final electrode voltage is swept. In a second step of this procedure, this electric field is taken into account by aligning the sample stage 122.The aforementioned process steps, i.e., the wobbling of the objective lens current I, the setting of the second aperture unit 109, the wobbling of the terminal electrode voltage AU and the positioning of the sample stage 122, can be repeated several times until no or only a minimal deflection of the image on the monitor 124 occurs.

[0113] The Fig. 14A and Fig. Figure 14B shows an embodiment of a method according to the invention, which can be used, for example, with the SEM 100 according to the Fig. 1, with the SEM 100A according to the Fig. 2, with the combination device 200 according to the Fig. 3 and / or with the particle beam device 400 according to the Fig. 4 is carried out. The following describes the execution of the procedure with the SEM 100 according to the Fig. 1 described. Regarding the execution of the procedure with the other aforementioned particle beam devices, the same applies and / or explicit reference is made below.

[0114] In process step S1C, a beam parameter is set to a reference value using a control unit. For example, the reference value is a zero value or a zero point. The control unit is, for example, the electron source control unit 126 for supplying the beam generator, in the form of the electron source 101, with an operating voltage in the form of the cathode voltage and for setting the cathode voltage. The beam parameter is then the cathode voltage. If the process is carried out with the SEM 100A according to the Fig. If procedure 2 is carried out, then, for example, the control unit is the terminal electrode control unit 128 for supplying the terminal electrode 112, 119 with a terminal electrode voltage and for setting the terminal electrode voltage. The beam parameter is then the terminal electrode voltage.

[0115] In process step S1C, the sample table 122 is also rotated to a predefinable reference position. The sample table 122 is rotated, for example, by rotating it around the first table rotation axis 603 and / or around the second table rotation axis 607 to the reference position.

[0116] In process step S2C, a first reference image of object 114 in the reference position is acquired. In process step S3C, the beam parameter is then set to a value that differs from the reference value. This setting is performed, for example, by one of the control units mentioned above, which is designed to adjust the corresponding beam parameter.

[0117] In process step S4C, a second reference image of object 114 is then acquired in the reference position. Thus, both the first and the second reference images are acquired in the reference position of the sample stage 122, but with different beam parameter values: one with the reference value and the other with a beam parameter value that differs from the reference value.

[0118] In process step S4C, the image shift of the second reference image relative to the first reference image is also calculated. This image shift is determined, for example, using cross-correlation.

[0119] In a further process step S5C, the beam parameter is again set to the reference value. The sample stage 122 is then rotated into a first position. This rotation occurs, for example, around the first stage rotation axis 603 and / or around the second stage rotation axis 607. In the first position of the sample stage 122, a first image of the object 114 is now acquired in process step S6C. The image shift of the first image relative to the first reference image is then calculated. This shift is determined, for example, by means of cross-correlation.

[0120] Following this, in process step S7C, the beam parameter is again set to a value that differs from the reference value. Then, in process step S8C, a second image of object 114 is acquired in the first position of the sample stage 122. Furthermore, the image shift of the second image relative to the first reference image is calculated. This image shift is also determined, for example, using cross-correlation.

[0121] In process step S9C, the beam parameter is again set to the reference value. The sample stage 122 is then rotated to a second position. This second position is set, for example, by rotating the sample stage 122 around the first stage rotation axis 603 and / or around the second stage rotation axis 607. Then, in process step S10C, a third image of the object 114 in the second position is acquired. Furthermore, the image shift of the third image relative to the first reference image is calculated, for example, by means of cross-correlation.

[0122] In process step S11C, the beam parameter is again set to a value that differs from the reference value. Then, in process step S12C, a fourth image of object 114 is acquired in the second position. Furthermore, the image shift of the fourth image relative to the first reference image is calculated, for example, by means of cross-correlation.

[0123] In process step S13C, the image shifts at the reference value are interpolated as a function of the position of the sample stage 122 from the image shifts of the first and third images. Furthermore, in process step S14C, the image shifts at a beam parameter value different from the reference value are interpolated as a function of the position of the sample stage 122 from the image shifts of the second reference image, the second image, and the fourth image.

[0124] In process step S15C, a target position of the sample stage 122 is determined at which the interpolated image shifts coincide at the reference value and at the beam parameter value differing from the reference value. In process step S16C, the beam parameter is again set to the reference value. The sample stage 122 is then rotated to the determined target position by rotating the sample stage 122 about the first stage rotation axis 603 and / or about the second stage rotation axis 607.

[0125] This method is particularly well suited for automation, since no value is constantly changed periodically, but rather a few discrete values ​​of a parameter are set and determined.

[0126] The features of the invention disclosed in this description, in the drawings, and in the claims can be essential for realizing the invention in its various embodiments, both individually and in any combination. The invention is not limited to the described embodiments. It can be varied within the scope of the claims and taking into account the knowledge of the person skilled in the art. Reference symbol list 100 SEM 100A SEM 101 Electron source 101A Suppressor electrode 102 Extraction electrode 103 Anode 104 Beam guide tube 104A Beam guide tube 105 first condenser lens 106 second condenser lens 107 lens 107A lens 108 first aperture unit 108A first aperture 109 second aperture unit 110 pole shoes 110A Pole shoes 111 Coil 111A coil 112 individual electrodes 112A single electrode 113 Pipe electrode 113A Pipe electrode 114 objects 115 Grid system 116 first detector 116A Counterfield grid 117 second detector 118 second aperture 119A electrode 120 sample chamber 121 third detector 122 Sample table 123 Control unit 124 Monitor 125 Lens control unit 126 Electron source control unit (radiator generator control unit) 127 Object voltage control unit 128 (first) terminal electrode control unit 129 second terminal electrode control unit 130 processor 131 first deflection unit 132 second deflection unit 133 Deflection control unit 134 Chamber detector 200 combination device 201 Sample chamber 300 ion beam device 301 Ion Beam Generators 302 Extraction electrode in the ion beam device 303 Condenser lens 304 additional lens elements 306 adjustable aperture 307 first electrode arrangement 308 second electrode arrangement 400 particle beam device with corrector unit 401 Particle beam column 402 Electron source 403 Extraction electrode 404 Anode 405 first electrostatic lens 406 second electrostatic lens 407 third electrostatic lens 408 magnetic deflection unit 409 first electrostatic beam deflection unit 409A first multipole unit 409B second multipole unit 410 Beam deflection device 411A first magnetic sector 411B second magnetic sector 411C third magnetic sector 411D fourth magnetic sector 411E fifth magnetic sector 411F sixth magnetic sector 411G seventh magnetic sector 413A first mirror electrode 413B second mirror electrode 413C third mirror electrode 414 electrostatic mirror 415 fourth electrostatic lens 416 second electrostatic beam deflection unit 416A third multipole unit 416B fourth multipole unit 417 third electrostatic beam deflection unit 418 fifth electrostatic lens 418A fifth multipole unit 418B sixth multipole unit 419 first analysis detector 420 Beam guide tube 421 Lens 422 magnetic lens 423 sixth electrostatic lens 424 Sample table 425 object 426 Sample chamber 427 Detection beam path 428 second analysis detector 429 Grid system 432 additional magnetic deflection element 600 first movement element 601 Housing 602 second movement element 603 first table rotation axis 604 third movement element 605 fourth movement element 606 fifth movement element 607 second table rotation axis 608 Control unit 609 bracket AU terminal electrode voltage AU1 Termination electrode voltage value I Objective lens current I1 Current value M1 first stepper motor M2 second stepper motor M3 third stepper motor M4 fourth stepper motor M5 fifth stepper motor OA optical axis OA1 first optical axis OA2 second optical axis OA3 third optical axis S1 to S16C process steps t time Operating voltage U1 voltage value

Claims

[1] Method for operating a particle beam device (100, 100A, 200, 400) with - at least one beam generator (101, 301, 402) for generating a particle beam with charged primary particles, - at least one objective lens (107, 107A, 304, 421) for focusing the particle beam onto the object (114, 425), wherein interaction particles and / or interaction radiation are generated upon interaction of the particle beam with the object (114, 425), wherein the objective lens (107, 107A, 304, 421) has at least one termination electrode (112, 112A, 119A, 423), - at least one movable sample stage (122, 424) for arranging the object (114, 425) in the particle beam device (100, 100A, 200, 400), wherein the sample stage (122, 424) is rotatable about a first axis (603) and / or a second axis (607) and wherein the first axis (603) is arranged perpendicular to the second axis (607), - at least one detector (116, 117, 121, 134, 419, 428) for detecting the interaction particles and / or interaction radiation and for generating detector signals, - at least one display device (124) for displaying an image of the object (114, 425) based on the detector signals, as well as - at least one control unit (125, 126, 127, 128, 129) for setting a beam parameter, the method comprising the following steps: a) Acquisition of reference images in a reference position of the sample stage (122, 424) using the following steps: - Taking a first reference image of the object (114, 425) in the reference position of the sample table (122, 424) with a beam parameter that has a value corresponding to a reference value; - Recording of a second reference image of the object (114, 425) in the reference position of the sample table (122, 424) with the beam parameter having a beam parameter value that is different from the reference value; - Calculating an image shift of the second reference image relative to the first reference image; b) Taking pictures in a first position of the sample table (122, 424) using the following steps: - Taking a first image of the object (114, 425) in the first position of the sample stage (122, 424) with the beam parameter having a value that corresponds to the reference value; - Taking a second image of the object (114, 425) in the first position of the sample stage (122, 424) with the beam parameter having a beam parameter value that is different from the reference value; - Calculating an image shift of the first image relative to the first reference image and calculating an image shift of the second image relative to the first reference image; c) Taking images in a second position of the sample table (122, 424) using the following steps: - Taking a third image of the object (114, 425) in the second position of the sample table (122, 424) with the beam parameter having a value that corresponds to the reference value; - Taking a fourth image of the object (114, 425) in the second position of the sample stage (122, 424) with the beam parameter having a beam parameter value that is different from the reference value; - Calculating an image shift of the third image relative to the first reference image and calculating an image shift of the fourth image relative to the first reference image; d) Interpolation of the image shifts of the first image and the third image recorded at the reference value with respect to the first reference image as a function of the position of the sample table (122, 424); e) Interpolation of the image shifts of the second reference image, the second image and the fourth image recorded at the respective beam parameter value with respect to the first reference image as a function of the position of the sample stage (122,424), wherein the beam parameter value is different from the reference value; f) Determining a target position of the sample stage (122, 424) at which the interpolated image shifts are identical at the reference value and at the beam parameter value that differs from the reference value; and g) Operating the particle beam device with the beam parameter having a value corresponding to the reference value and with the sample table (122, 424) positioned in the target position. [2] The method of claim 1, comprising at least one of the following steps: - Setting the beam parameter to the reference value; - Setting the beam parameter to a value that differs from the reference value; - Setting the reference position of the sample table (122, 424) by rotating the sample table (122, 424) about the first axis (603) and / or about the second axis (607); - Setting the first position of the sample table (122, 424) by rotating the sample table (122, 424) about the first axis (603) and / or about the second axis (607); - Setting the second position of the sample table (122, 424) by rotating the sample table (122, 424) about the first axis (603) and / or about the second axis (607). [3] Method according to claim 1 or 2, wherein the control unit is an objective lens control unit (125) for supplying the objective lens (107, 107A, 304, 421) with an objective lens current (I) and for adjusting the objective lens current (I) and wherein the beam parameter is the objective lens current (I). [4] Method according to claim 1 or 2, wherein the control unit is a beam generator control unit (126) for supplying the beam generator (103, 402) with an operating voltage (U) and for adjusting the operating voltage (U) and wherein the beam parameter is the operating voltage (U). [5] Method according to claim 1 or 2, wherein the control unit is a terminal electrode control unit (128, 129) for supplying the terminal electrode (112, 112A, 119A) with a terminal electrode voltage (AU) and for adjusting the terminal electrode voltage (AU) and wherein the beam parameter is the terminal electrode voltage (AU). [6] Method according to claim 1 or 2, wherein the control unit is a deflection control unit (133) for supplying a deflection unit (131, 132) with a control variable and for adjusting the control variable and wherein the beam parameter is the control variable. [7] Method according to any one of claims 1 to 6, wherein the method comprises the following steps: a) Taking another image of the object (114, 425) at another position of the sample table (122, 424) with the beam parameter having the value corresponding to the reference value; b) Taking another image of the object (114, 425) with the beam parameter having a value different from the reference value; c) Calculating an image shift of the subsequent image relative to the first reference image; d) Calculating an image shift of the further image relative to the first reference image; e) Interpolation of the image shift of the further image with respect to the first reference image as a function of the further position of the sample table taking into account the interpolation according to step d) of claim 1; f) Interpolation of the image shift of the further image with respect to the first reference image as a function of the further position of the sample table taking into account the interpolation according to step e) of claim 1; g) Determining a further target position of the sample stage (122, 424) where the interpolated image shifts are identical at the reference value and at the beam parameter value that differs from the reference value; and h) Operating the particle beam device with the beam parameter having a value corresponding to the reference value and with the sample table (122, 424) arranged in the further target position. [8] Computer program product comprising a program code that can be loaded into a processor (130) of a particle beam device (100, 100A, 200, 400) and, when implemented, controls a particle beam device (100, 100A, 200, 400) such that a method according to one of the preceding claims is carried out. [9] Particle beam device (100, 100A, 200, 400) for imaging and / or processing an object (114, 425), with - at least one beam generator (101, 301, 402) for generating a particle beam with charged primary particles, - at least one objective lens (107, 107A, 304, 421) for focusing the particle beam onto the object (114, 425), wherein interaction particles and / or interaction radiation are generated upon interaction of the particle beam with the object (114, 425), wherein the objective lens (107, 107A, 304, 421) has at least one termination electrode (112, 112A, 119A, 423), - at least one adjustable deflection unit (131, 132) for deflecting the particle beam and / or at least one adjustable aperture unit (109) for shaping the particle beam, - at least one movable sample table (122, 424) for arranging the object (114, 425) in the particle beam device (100, 100A, 200, 400), - at least one detector (116, 117, 121, 134, 419, 428) for detecting the interaction particles and / or interaction radiation and for generating detector signals, - at least one display device (124) for displaying an image of the object (114, 425) based on the detector signals, - at least one objective lens control unit (125) for supplying the objective lens (107, 107A, 304, 421) with an objective lens current (I) and for adjusting the objective lens current (I), - at least one radiation generator control unit (126) for supplying the radiation generator (101, 402) with an operating voltage (U) and for adjusting the operating voltage (U), - at least one termination electrode control unit (128, 129) for supplying the termination electrode (112, 112A, 119A) with a termination electrode voltage (AU) and for adjusting the termination electrode voltage (AU), - at least one deflection control unit (133) for supplying the deflection unit (131, 132) and / or the aperture unit (109) with a control variable and for adjusting the control variable, wherein the particle beam device (100, 100A, 200, 400) has a processor (130) in which a computer program product according to claim 8 is loaded. [10] Particle beam device (100, 100A, 200, 400) according to claim 9, wherein the beam generator has a cathode (101, 402) and wherein the operating voltage (U) is a cathode voltage supplied to the cathode (101, 402) by the beam generator control unit (126). [11] Particle beam device (100, 100A, 200, 400) according to claim 9 or 10, wherein the particle beam device (100, 100A, 200, 400) has an object voltage control unit (127) for supplying the object (114, 425) with object voltage. [12] Particle beam device (100, 100A, 200, 400) according to any one of claims 9 to 11, wherein the particle beam device (100, 100A, 200, 400) has at least one corrector (414) for correcting chromatic and / or spherical aberration. [13] Particle beam device (100, 100A, 200, 400) according to claim 12, wherein the corrector (414) is a mirror corrector. [14] Particle beam device (100, 100A, 200, 400) according to any one of claims 9 to 13, wherein the particle beam device (100, 100A, 200, 400) is designed as an electron beam device and / or as an ion beam device. [15] Particle beam device (200) according to one of claims 9 to 14, wherein the beam generator (101) for generating a particle beam with charged primary particles is configured as a first beam generator for generating a first particle beam with first charged primary particles and the objective lens (107, 107A) is configured as a first objective lens for focusing the first particle beam, and wherein the particle beam device (200) further comprises: - at least one second beam generator (301) for generating a second particle beam with second charged primary particles, and - at least one second objective lens (304) for focusing the second particle beam onto the object (114).

Images