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 for imaging, analyzing, and / or processing an object. Furthermore, the invention relates to a computer program and a particle beam device for carrying out the method.The method comprises guiding a particle beam by means of a first guiding device and a second guiding device such that the particle beam is guided to first positions on a surface of the object, wherein the first positions are arranged along a first geometric shape on the object, and comprises guiding the particle beam by means of the first guiding device and the second guiding device such that the particle beam is guided to second positions on the surface of the object, wherein the second positions are arranged along a second geometric shape on the object, wherein guiding the particle beam along the first geometric shape and / or along the second geometric shape is faster in time than guiding the particle beam from the first geometric shape to the second geometric shape.

Description

[0001] The invention relates to a method for operating a particle beam device for imaging, analyzing, and / or processing an object. Furthermore, the invention relates to a computer program product and a particle beam device for carrying out the method. For example, the particle beam device is designed as an electron beam device and / or ion beam device.

[0002] An electron beam device, in particular a scanning electron microscope (hereinafter also referred to as SEM) and / or a transmission electron microscope (hereinafter also referred to as TEM), is used to examine objects (hereinafter also referred to as samples) in order to gain insights into their properties and behavior under certain conditions.

[0003] In an SEM, an electron beam (hereinafter also referred to as the primary electron beam) is generated by a beam generator and focused onto an object to be examined using a beam guidance system. The primary electron beam is guided over the surface of the object to be examined using a deflection device in the form of a scanning device. The electrons of the primary electron beam interact with the object to be examined. Due to the interaction, electrons (so-called secondary electrons) are emitted from the object and electrons of the primary electron beam are scattered back (so-called backscattered electrons). The secondary electrons and the backscattered electrons are detected and used for imaging. This produces an image of the object to be examined.Furthermore, the interaction generates interaction radiation, for example X-rays or cathodoluminescence light, which is detected by a detector to analyze the object and then evaluated.

[0004] In a TEM, a primary electron beam is generated by a beam generator and focused onto an object under investigation using a beam guidance system. The primary electron beam passes through the object under investigation. As the primary electron beam passes through the object under investigation, the electrons in the primary electron beam interact with the material of the object under investigation. The electrons that pass through the object under investigation are imaged onto a luminescent screen or a detector (e.g., a camera) by a system with an objective lens and a projection lens. Imaging can also be performed in the scanning mode of a TEM. Such a TEM is commonly referred to as a STEM.In addition, it may be provided to detect electrons scattered back from the object to be examined and / or secondary electrons emitted by the object to be examined with a further detector in order to image the object to be examined.

[0005] It is known to combine the functions of a STEM and an SEM in a single particle beam device. This particle beam device thus enables the analysis and imaging of objects with an SEM function and / or a STEM function.

[0006] Furthermore, a particle beam device with an ion beam column is known. Ions are generated using an ion beam generator arranged in the ion beam column. The ions are used to process an object. During processing, for example, material from the object is removed from the object or material is applied to the object, particularly with the addition of a gas. Additionally or alternatively, the ions are used for imaging.

[0007] Furthermore, a combination device is known which is used for imaging, analyzing, and / or processing an object. The combination device is designed to direct both electrons and ions onto an object to be examined. For example, it is known to additionally equip an SEM with an ion beam column. An ion beam generator arranged in the ion beam column generates ions which are used to process the object (e.g., removing material from the object or applying material to the object) or to image the object. For this purpose, the ions are guided over the object by means of a deflection device in the form of a scanning device. The SEM is used in particular for observing the processing, but also for further examination (imaging and / or analysis) of the processed or unprocessed object.

[0008] A particle beam device can image an object with high spatial resolution. This can be achieved by using a primary electron beam with a very small diameter in the plane of the object. Furthermore, the spatial resolution can be improved the more the electrons of the primary electron beam are initially accelerated in the particle beam device and then decelerated to a desired energy (hereinafter referred to as landing energy) at the end in the objective lens or in the region of the objective lens. For example, the electrons of the primary electron beam are accelerated with an acceleration voltage of 2 kV to 30 kV and guided through an electron beam column of the particle beam device. In the region between the objective lens and the object, the electrons of the primary electron beam are decelerated to the desired landing energy with which they impact the object.For example, the landing energy of the electrons in the primary electron beam is in the range of 10 eV to 30 keV.

[0009] It is known to provide a particle beam device with a scanning system for guiding a particle beam (for example, the primary electron beam or an ion beam) over an object. For example, the scanning system is designed as a deflection system. The deflection system can have a first deflection device and a second deflection device, wherein the first deflection device and the second deflection device are arranged one after the other along an optical axis of the particle beam device. By combining the deflections of the particle beam with the first deflection device and the second deflection device, the position of a virtual pivot point of the particle beam can be shifted along the optical axis of the particle beam device. The deflection of the particle beam is apparently generated virtually by an inclination about the virtual pivot point.

[0010] A method used to image defects in crystalline materials is known from the prior art. The method is called electron channeling contrast imaging (hereinafter also referred to as ECCI). It is based on the effects of electron channeling and diffraction produced when a primary electron beam passes through a crystal lattice of an object. Depending on the direction of the primary electron beam with respect to the crystal lattice, the density of electrons backscattered by the object changes. The crystal lattice defects can thus be monitored by recording the image generated by the backscattered electrons while the incident primary electron beam is scanned across the object. The density of backscattered electrons is minimal for the given direction of the primary electron beam when one set of lattice planes is close to the Bragg condition.In this case, most of the electrons are channeled through the crystalline lattice.

[0011] ECCI can be combined with another method known from the prior art, known as rocking beam. This further known method involves sweeping the primary electron beam over a specific angular range and directing the incident primary electron beam to a single position on the surface of the object. This further known method involves the use of a two-stage beam deflection system. The primary electron beam is deflected away from the optical axis of the particle beam device by a first deflection device (also called first guide device) and synchronously deflected back onto the optical axis by a second deflection device (also called second guide device). The primary electron beam is irradiated at the same point on the object using an objective lens. This further known method is carried out over a specific angular range.The further known method can also be described as follows. The primary electron beam is guided to a specific location within a scanning region on the surface of the object by means of (i) a first guide device provided for guiding the primary electron beam and (ii) a second guide device provided for guiding the primary electron beam. Viewed from the beam generator toward the object, the first guide device is arranged first, followed by the second guide device. The first guide device guides the primary electron beam away from the optical axis at a first angle with respect to the optical axis. The second guide device guides the primary electron beam toward the optical axis at a second angle with respect to the optical axis. The first angle and the second angle may be identical.The first angle passes through a first predeterminable range of values ​​and the second angle passes through a second predeterminable range of values ​​when the primary electron beam is guided to the position of the scanning area.

[0012] With regard to the state of the art, reference is made to DE 11 2016 005 577 B4 and US 2020 / 0013581 A1.

[0013] The use of an objective lens in a particle beam device can cause aberrations, particularly spherical aberrations, which can lead to distortion. This distortion causes unwanted deflections of the particle beam.

[0014] The invention is therefore based on the object of creating a method, a computer program product and a particle beam device for carrying out the method, with which undesired deflections of the particle beam caused by aberrations are reduced or avoided.

[0015] According to the invention, this object is achieved by a method having the features of claim 1. A computer program product having program code that controls a particle beam device for carrying out the method is provided by the features of claim 10. Furthermore, a particle beam device for imaging, analyzing, and / or processing an object is provided by the features of claim 11. Further features of the invention will become apparent from the following description, the appended claims, and / or the appended drawings.

[0016] The method according to the invention is used to operate a particle beam device for imaging, analyzing, and / or processing an object. The particle beam device comprises at least one beam generator for generating a particle beam with charged particles. For example, the charged particles are electrons or ions. Furthermore, the particle beam device can comprise an objective lens for focusing the particle beam onto the object.

[0017] The method according to the invention comprises guiding the particle beam to the object. In particular, the particle beam is guided away from an optical axis of the particle beam device at a first angle with respect to the optical axis by means of a first guiding device. Furthermore, the method according to the invention comprises guiding the particle beam by means of a second guiding device, wherein the particle beam is guided to the optical axis at a second angle with respect to the optical axis such that the particle beam is guided to first positions on a surface of the object. The first positions are arranged along a first geometric shape on the surface of the object. The first geometric shape can be any geometric shape. Embodiments of the first geometric shape are discussed further below.The first guide device may be a first deflection device, such as a first magnetic and / or electrostatic deflection device. The second guide device may be a second deflection device, such as a second magnetic and / or electrostatic deflection device.

[0018] The method according to the invention further comprises guiding the particle beam away from the optical axis by means of the first guiding device at a third angle with respect to the optical axis. Furthermore, the method according to the invention comprises guiding the particle beam by means of the second guiding device, wherein the particle beam is guided to the optical axis at a fourth angle with respect to the optical axis such that the particle beam is guided to second positions on the surface of the object. The second positions are arranged along a second geometric shape on the surface of the object. The second geometric shape can be any geometric shape. Embodiments of the second geometric shape are discussed further below.

[0019] The method according to the invention provides a first guidance signal for guiding the particle beam by means of a control device of the particle beam device. The first guidance signal is supplied to the first guidance device from the control device using a first signal connection between the control device and the first guidance device. The first signal connection can be a physical connection, such as a connecting line, and / or a wireless connection, such as a radio communication system and / or a wireless local area network.

[0020] The method according to the invention further provides a second guidance signal for guiding the particle beam by means of the control device of the particle beam device. The second guidance signal is supplied to the second guidance device from the control device using a second signal connection between the control device and the second guidance device. The second signal connection can be a physical connection, such as a connecting line, and / or a wireless connection, such as a radio communication system and / or a wireless local area network.

[0021] The method according to the invention further comprises providing the first guidance signal and the second guidance signal as a function of a first distance from a center point arranged on the surface of the object to the first geometric shape. The first guidance signal and the second guidance signal are used to guide the particle beam along the first geometric shape. The first distance can be a distance from the center point to one of the first positions arranged on the first geometric shape. For example, the distance can be the shortest distance of all distances from the center point to the first positions arranged on the first geometric shape.

[0022] Furthermore, the method according to the invention comprises providing the first guidance signal and the second guidance signal as a function of a second distance between the center point arranged on the surface of the object and the second geometric shape. The first guidance signal and the second guidance signal are used to guide the particle beam along the second geometric shape. The second distance can be a distance between the center point and one of the second positions arranged on the second geometric shape. For example, the distance can be the shortest distance of all distances between the center point and the second positions arranged on the second geometric shape.

[0023] According to the invention, guiding the particle beam along the first geometric shape and / or along the second geometric shape is faster in time than guiding the particle beam from the first geometric shape to the second geometric shape.

[0024] It has been found that the method according to the invention reduces or avoids undesired deflections of the particle beam caused by aberrations, in particular aberrations generated by an objective lens of the particle beam. The aberrations can be spherical aberrations. The invention offers the possibility of adapting the first guide signal and the second guide signal by means of the control device such that the undesired deflections caused by the aberrations are compensated. For example, the first guide signal and the second guide signal are adapted as a function of the first distance and the second distance. Embodiments for adapting the first guide signal and the second guide signal are discussed further below.

[0025] An embodiment of the method according to the invention additionally or alternatively comprises at least one of the following steps: (i) using a circular shape as the first geometric shape; (ii) using a circular shape as the second geometric shape; (iii) using a first circle as the first geometric shape; and (iv) using a second circle as the second geometric shape. It is expressly noted that the invention is not limited to these geometric shapes. Rather, any geometric shape suitable for the invention may be used.

[0026] The first geometric shape, in particular a first circular shape and / or a first circle, can be determined by the center point and by a first radius extending from the center point along the surface of the object. The second geometric shape, in particular a second circular shape and / or a second circle, can be determined by the center point and by a second radius extending from the center point along the surface of the object. A further embodiment of the method according to the invention additionally or alternatively comprises: (i) providing the first guide signal and the second guide signal as a function of the first radius for guiding the particle beam along the first geometric shape and (ii) providing the first guide signal and the second guide signal as a function of the second radius for guiding the particle beam along the second geometric shape.

[0027] As mentioned above, the first geometric shape and the second geometric shape may be any geometric shapes. Therefore, a further embodiment of the method according to the invention additionally or alternatively comprises: (i) using a first polygon as the first geometric shape; and (ii) using a second polygon as the second geometric shape. For example, the first geometric shape may be a triangle or a square. Furthermore, the second geometric shape may be a triangle or a square. As mentioned above, the invention is not limited to these geometric shapes. Rather, any geometric shape suitable for the invention may be used.

[0028] A further embodiment of the method according to the invention additionally or alternatively provides that the first distance is smaller than the second distance. Furthermore, the method according to the invention comprises: (i) providing the first guide signal with a first gain factor of a first amplifier by the control device and (ii) providing the second guide signal with a second gain factor of a second amplifier by the control device. The ratio of the first gain factor to the second gain factor is higher when guiding the particle beam along the second geometric shape than when guiding the particle beam along the first geometric shape.

[0029] The aforementioned amplification factors are selected depending on the distances. As mentioned above, the first guide signal and the second guide signal are provided by the control device. The control device may comprise or be connected to an amplifier for providing the first guide signal and the second guide signal. The amplifier is designed to increase or decrease the first guide signal using the first amplification factor and / or the second guide signal using the second amplification factor. Additionally or alternatively, the control device may comprise or be connected to the first amplifier for providing the first guide signal. Furthermore, the control device may comprise or be connected to the second amplifier for providing the second guide signal.The first amplifier is configured to increase or decrease the first command signal using the first gain factor. Furthermore, the second amplifier is configured to increase or decrease the second command signal using the second gain factor.

[0030] A further embodiment of the method according to the invention additionally or alternatively provides for the first guide signal to be used as the second guide signal. Furthermore, a further embodiment of the method according to the invention additionally or alternatively provides for the first amplification factor to be constant, while the second amplification factor is different when guiding the particle beam along the second geometric shape and when guiding the particle beam along the first geometric shape. Alternatively, the second amplification factor is constant, while the first amplification factor is different when guiding the particle beam along the second geometric shape and when guiding the particle beam along the first geometric shape. The aforementioned embodiments can be used in particular when the first guide signal is used as the second guide signal.

[0031] A further embodiment of the method according to the invention additionally or alternatively provides control signals that are used to control the objective lens as a function of (i) the first distance of the center point to the first geometric shape and (ii) the second distance of the center point to the second geometric shape. In particular, this embodiment of the method according to the invention comprises the control device supplying a first control signal to the objective lens of the particle beam device as a function of the first distance for focusing the particle beam along the first geometric shape. Additionally or alternatively, the method according to the invention comprises the control device supplying a second control signal to the objective lens of the particle beam device as a function of the second distance for focusing the particle beam along the second geometric shape.Additionally or alternatively, the method according to the invention comprises: (i) using an analog signal or a digital signal as the first control signal; and (ii) using an analog signal or a digital signal as the second control signal. The first control signal and / or the second control signal are / is used to further reduce or avoid spherical aberrations. In particular, the first control signal can be used to refocus the particle beam to the first positions. In a further embodiment of the method according to the invention, the first control signal in the form of a first analog signal can be used to refocus the particle beam to the first positions. Furthermore, the second control signal can be used to refocus the particle beam to the second positions.In a further embodiment of the method according to the invention, the second control signal in the form of a second analog signal can be used to refocus the particle beam to the second positions. Additionally or alternatively, the first control signal in the form of a first digital signal and / or the second control signal in the form of a second digital signal can be used to control a digital-to-analog converter used to generate a focus signal for the objective lens of the particle beam device.

[0032] An embodiment of the method according to the invention additionally or alternatively comprises at least one of the following steps: (i) using the second angle as the first angle; and (ii) using the fourth angle as the third angle. In other words, the first angle may be identical to the second angle. Furthermore, the third angle may be identical to the fourth angle.

[0033] A further embodiment of the method according to the invention additionally or alternatively provides for the rocking beam method to be carried out at least at one of the first positions and / or at least at one of the second positions. In other words, at at least one of the first positions, the first angle passes through a first predeterminable value range and the second angle passes through a second predeterminable value range when the particle beam is guided to the respective position of the first positions. Additionally or alternatively, at at least one of the second positions, the third angle passes through a third predeterminable value range and the fourth angle passes through a fourth predeterminable value range when the particle beam is guided to the respective position of the second positions.Each of the aforementioned predeterminable value ranges can comprise angles in the range from 0° to 90°, wherein the boundaries can be contained within the aforementioned predeterminable value ranges. A further embodiment of the method according to the invention additionally or alternatively provides for the rocking beam method to be carried out at each of the first positions and / or at each of the second positions.

[0034] All of the above and following embodiments of the method according to the invention are not limited to the explained sequence of method steps. The invention also encompasses other sequences of method steps that are suitable for achieving the object of the invention. Additionally or alternatively, the method according to the invention also provides for parallel execution of at least two method steps. Furthermore, the above and following embodiments of the method according to the invention are not limited to the entirety of all method steps mentioned above or below. In particular, in further embodiments, one or more of the above or below method steps are to be omitted.

[0035] The invention further relates to a computer program product comprising program code that is loadable or is loaded into a processor of a particle beam device. When executed in the processor, the program code controls the particle beam device to carry out a method that has at least one of the above or following features or a combination of at least two of the above or following features. In other words, the invention further relates to a non-transitory and computer-readable medium containing software that is loadable or is loaded into a processor of a particle beam device. When executed in the processor, the software controls the particle beam device to carry out a method that has at least one of the above or following features or a combination of at least two of the above or following features.The software includes executable code for performing at least one of the method steps explained above or below.

[0036] Therefore, the invention also relates to a processor that is designed to perform a method having at least one of the above or below features or a combination of at least two of the above or below features.

[0037] The invention further relates to a particle beam device for imaging, analyzing, and / or processing an object, wherein the particle beam device has been explained above and will be specified in more detail below. This will be briefly summarized below. The particle beam device according to the invention comprises at least one beam generator for generating a particle beam that comprises charged particles.

[0038] The charged particles are, for example, electrons or ions. Furthermore, the particle beam device according to the invention comprises at least one first guide device for guiding the particle beam and at least one second guide device for guiding the particle beam. The first guide device can be a first deflection device, such as a first magnetic and / or electrostatic deflection device. The second guide device can be a second deflection device, such as a second magnetic and / or electrostatic deflection device. Furthermore, the particle beam device according to the invention comprises at least one control device for supplying a first guide signal to the first guide device and a second guide signal to the second guide device for guiding the particle beam.Furthermore, the particle beam device according to the invention comprises at least one first signal connection arranged between the control device and the first guide device, and at least one second signal connection arranged between the control device and the second guide device. The first signal connection and / or the second signal connection can be a physical connection such as a connecting line and / or a wireless connection such as a radio communication system and / or a wireless local area network. In addition, the particle beam device according to the invention comprises at least one processor arranged in or on the control device and into which a computer program product having the features mentioned above or below is loaded.

[0039] In one embodiment of the particle beam device according to the invention, the particle beam device additionally or alternatively comprises at least one scanning device for guiding the particle beam over the object, wherein the scanning device comprises the first guiding device and the second guiding device.

[0040] In a further embodiment of the particle beam device according to the invention, the particle beam device additionally or alternatively comprises at least one detector for detecting interaction particles and / or interaction radiation resulting from an interaction of the particle beam with the object when the particle beam impinges on the object. The interaction particles can be secondary electrons, backscattered electrons, and / or secondary ions. The interaction radiation can be X-rays and / or cathodoluminescent light.

[0041] In a further embodiment of the particle beam device according to the invention, the particle beam device additionally or alternatively comprises at least one objective lens for focusing the particle beam onto the object. For example, the first guide device and / or the second guide device are / is arranged within the objective lens of the particle beam device. In particular, the first guide device and / or the second guide device can be arranged within the objective lens along the optical axis of the particle beam device. For example, the first guide device can be designed as a first electrostatic and / or magnetic deflection device. Furthermore, the second guide device can be designed as a second electrostatic and / or magnetic deflection device.

[0042] In a further embodiment of the particle beam device according to the invention, the particle beam device additionally or alternatively comprises a first amplifier connected to the first guide device and a second amplifier connected to the second guide device.

[0043] In yet another embodiment of the particle beam device according to the invention, it is additionally or alternatively provided that the beam generator is a first beam generator and that the particle beam is a first particle beam with first charged particles. The objective lens is a first objective lens for focusing the first particle beam onto the object. Furthermore, the particle beam device according to the invention comprises at least one second beam generator for generating a second particle beam with second charged particles. Furthermore, the particle beam device according to the invention comprises at least one second objective lens for focusing the second particle beam onto the object.

[0044] In particular, it is provided that the particle beam device according to the invention is designed as an electron beam device and / or as an ion beam device.

[0045] Further practical embodiments and advantages of the invention are described below in connection with the following figures: Fig. 1 shows a schematic representation of a first embodiment of a particle beam device according to the invention; Fig. Figure 2 shows a schematic representation of a second embodiment of a particle beam device according to the invention; Fig. 3 shows a schematic representation of a third embodiment of a particle beam device according to the invention; Fig. 4 shows a schematic representation of an embodiment of a movable stage; Fig. 5 shows a further schematic representation of the embodiment of the movable object stage according to Fig. 4; Fig. 6 shows a schematic representation of a sequence of a first embodiment of the method according to the invention; Fig. 7 shows a schematic representation of a first geometric shape with first positions and a second geometric shape with second positions; Fig. 8 shows a further schematic representation of a first geometric shape with first positions and a second geometric shape with second positions; Fig. 9 shows a schematic representation of a control device connected to units of a particle beam device; and Fig. 10 shows a schematic representation of a sequence of a second embodiment of the method according to the invention.

[0046] The invention will now be explained in more detail using a particle beam device in the form of an SEM and a combination device consisting of an electron beam column and an ion beam column. It should be expressly noted that the invention can be used with any particle beam device, in particular with any electron beam device and / or any ion beam device.

[0047] Fig. Figure 1 shows a schematic representation of a first embodiment of a particle beam device according to the invention in the form of an SEM 100. The SEM 100 has a beam generator 1 with an electron source, an extraction electrode 2, a control electrode 3, and an anode 4. The anode 4 forms a source-side end of a beam guide tube 21 of the SEM 100. The beam generator 1 is designed, for example, as a thermal field emitter. Alternatively, the beam generator 1 is designed, for example, as a thermal tungsten emitter or as an LAB. 6 -Emitter trained.

[0048] Electrons emitted from the beam generator 1 form a primary electron beam. The electrons are accelerated to the anode potential due to a potential difference between the beam generator 1 and the anode 4. For example, the potential of the anode 4 is 1 kV to 30 kV positive relative to the potential of the beam generator 1, so the electrons have a kinetic energy in the range between 1 keV and 30 keV.

[0049] Starting from the anode 4 and viewed in the direction of an objective lens 10 along an optical axis 20, the SEM 100 comprises first a first condenser lens 5 and then a second condenser lens 6. Between the first condenser lens 5 and the second condenser lens 6, an aperture unit 7 is arranged in the beam guide tube 21. In the Fig. In the SEM 100 shown in Figure 1, the objective lens 10 is designed as a magnetic lens having a pole piece 22 with a pole piece gap 23. An annular coil 11 for generating a magnetic field of the objective lens 10 is arranged in the pole piece 22.

[0050] Starting from the second condenser lens 6 and viewed in the direction of the objective lens 10, a guide device in the form of a deflection device is arranged along the optical axis 20 of the SEM 100. The guide device has a first guide device in the form of a first deflection device 9 and a second guide device in the form of a second deflection device 12. The first deflection device 9 is arranged on the source side of the objective lens 10. The second deflection device 12, in contrast, is arranged on the object side within the objective lens 10 on the beam guide tube 21. The first deflection device 9 and the second deflection device 12 are crossed deflection devices. In other words, both the first deflection device 9 and the second deflection device 12 are designed to deflect the primary electron beam in two non-parallel directions that are oriented perpendicular to the direction of the optical axis 20.For example, the first deflection device 9 and / or the second deflection device 12 is / are (a) magnetic deflection device(s). In particular, the first deflection device 9 and / or the second deflection device 12 has / have, for example, four air-core coils arranged around the optical axis 20 of the SEM 100. Additionally or alternatively, the first deflection device 9 and / or the second deflection device 12 is / are (a) electrostatic deflection device. In particular, the first deflection device 9 and / or the second deflection device 12 has / have, for example, four electrodes arranged around the optical axis 20 of the SEM 100, to which different electrostatic potentials can be applied.

[0051] The objective lens 10 is arranged on an object chamber 13. In particular, the objective lens 10 protrudes through an opening of the object chamber 13 into an interior of the object chamber 13. A movable object stage 19 is arranged in the interior of the object chamber 13. An object 15 can be arranged on the object stage 19.

[0052] The primary electron beam generated by the beam generator 1 and shaped by the first condenser lens 5 and / or the second condenser lens 6 is focused in an object plane 16 by means of the objective lens 10. Suitable excitations of the first deflection device 9 and the second deflection device 12 ensure that the primary electron beam can be deflected in the object plane 16 perpendicular to the optical axis 20 of the SEM 100 such that the surface of the object 15 arranged in the object plane 16 can be scanned by different deflections of the primary electron beam. The electrons of the primary electron beam interact with the object 15. Due to the interaction, electrons (so-called secondary electrons) are emitted from the object 15, and electrons of the primary electron beam are scattered back (so-called backscattered electrons). The secondary electrons and the backscattered electrons are detected and used to generate an image.Thus, an image of the object 15 to be examined is obtained. Furthermore, interaction radiation such as X-rays or cathodoluminescence light is generated during the interaction, which is detected and subsequently evaluated for the analysis of the object 15.

[0053] For detecting the aforementioned interaction particles and / or the aforementioned interaction radiation, a first detector unit 14 is arranged in the object chamber 13, for example. Additionally or alternatively, a second detector unit 8 for detecting the aforementioned interaction particles is arranged, for example, in the region between the first deflection device 9 and the second condenser lens 6 in the beam guide tube 21.

[0054] At the Fig. In the embodiment of the SEM 100 shown in Figure 1, a pressure diaphragm holder 17 is provided, which can be arranged on the pole piece 22 of the objective lens 10 projecting into the object chamber 13. The pressure diaphragm holder 17 has a pressure diaphragm with a diaphragm opening 18. Additional pressure diaphragm units can be arranged, for example, within the beam guide tube 21 of the SEM 100. These are shown in Fig. 1 not shown. Vacuum pumps required to create and maintain the vacuum within the beam guide tube 21 and the object chamber 13 and to operate the SEM 100 are shown in Fig. 1 is also not shown.

[0055] If the SEM 100 is operated in the specimen chamber 13 under high vacuum, the pressure stage diaphragm holder 17 is not absolutely necessary and can accordingly be located away from the pole piece 22 of the objective lens 10. However, if the SEM 100 is operated at relatively high pressure (pressures in the range of approximately 1 to 3000 Pa) in the specimen chamber 13, the pressure stage diaphragm holder 17 can be mounted on the pole piece 22 of the objective lens 10, so that despite the higher pressure in the specimen chamber 13, a sufficiently good vacuum can be maintained within the beam guide tube 21 by differential pumping.

[0056] In particular, the first detector unit 14, the second detector unit 8, the first deflection device 9, and the second deflection device 12 are connected to a control device 123, which comprises a monitor 124. In particular, the first deflection device 9 is connected to the control device 123 by a first signal connection 800. The first signal connection 800 can be a physical connection, such as a connecting line, and / or a wireless connection, such as a radio communication system and / or a wireless local area network. The second deflection device 12 is connected to the control device 123 by a second signal connection 801. The second signal connection 801 can be a physical connection, such as a connecting line, and / or a wireless connection, such as a radio communication system and / or a wireless local area network.The control device 123 processes detection signals generated by the first detector unit 14 and the second detector unit 8 and displays them in the form of images on the monitor 124. The control device 123 further comprises a database 126 in which data is stored and from which data is read. Furthermore, the control device 123 is connected to other units of the SEM 100. This is shown in FIG. Fig. 1 not shown further.

[0057] The control device 123 of the SEM 100 includes a processor 127. A computer program product comprising program code is loaded into the processor 127. When executed, the program code executes a method for operating the SEM 100. This is explained in more detail below.

[0058] In the SEM 100, it is possible to set a distance A by means of the control device 123 of the SEM 100. The distance A is given either (a) by an object distance between an outer boundary of the objective lens 10 of the SEM 100 and the object 15 or (b) by a focal plane distance between the outer boundary of the objective lens 10 of the SEM 100 and a focal plane of the objective lens 10. The aforementioned distance A according to case (a) or case (b) is also referred to as the working distance. For example, the distance A in case (a) is set by moving the stage 19 and / or moving the objective lens 10 with a movement device 25. In particular, the distance A in case (b) is set by varying an excitation of the objective lens 10 along the optical axis 20 of the SEM 100.

[0059] Fig. 2 shows a schematic representation of another SEM 100. The other SEM 100 has a first beam generator in the form of an electron source 101, which is designed as a cathode. Furthermore, the other SEM 100 is provided with an extraction electrode 102 and an anode 103, which is arranged at one end of a beam guide tube 104 of the other SEM 100. For example, the electron source 101 is designed as a thermal field emitter. However, the invention is not limited to such an electron source 101. Rather, any electron source suitable for the invention can be used.

[0060] Electrons emitted by the electron source 101 form a primary electron beam. The electrons are accelerated to anode potential due to a potential difference between the electron source 101 and the anode 103. In the embodiment shown here, the anode potential is 100 V to 35 kV relative to a ground potential of a housing of a specimen chamber 120, for example, 5 kV to 15 kV, in particular 8 kV. However, it could alternatively also be at ground potential.

[0061] Two condenser lenses are arranged on the beam guide tube 104, namely a first condenser lens 105 and a second condenser lens 106. Starting from the electron source 101 and viewed in the direction of a first objective lens 107, the first condenser lens 105 is arranged first, followed by the second condenser lens 106. It should be expressly noted that further embodiments of the further SEM 100 can have only a single condenser lens. A first diaphragm unit 108 is arranged between the anode 103 and the first condenser lens 105. The first diaphragm unit 108, together with the anode 103 and the beam guide tube 104, is at high voltage potential, namely the potential of the anode 103 or to ground. The first diaphragm unit 108 has numerous first diaphragm openings 108A, one of which is Fig. 2. For example, two first apertures 108A are provided. Each of the plurality of first apertures 108A has a different aperture diameter. By means of an adjustment mechanism (not shown), it is possible to adjust a desired first aperture 108A to an optical axis OA of the further SEM 100. It should be expressly noted that the first aperture unit 108 of further embodiments may be provided with only a single first aperture 108A. In this embodiment, no adjustment mechanism may be provided, and the first aperture unit 108 is stationary. A stationary second aperture unit 109 is arranged between the first condenser lens 105 and the second condenser lens 106. Alternatively, the second aperture unit 109 may be movable.

[0062] The first objective lens 107 has pole pieces 110 with a bore. The beam guide tube 104 is guided through this bore. A coil 111 is arranged in the pole pieces 110.

[0063] An electrostatic delay system is arranged in a lower region of the beam guide tube 104. The electrostatic delay system has a single electrode 112 and a tubular electrode 113. The tubular electrode 113 is arranged at one end of the beam guide tube 104 facing an object 125 arranged on a movable object holder 114.

[0064] The tube electrode 113, together with the beam guide tube 104, is at the potential of the anode 103, while the individual electrode 112 and the object 125 are at a potential that is lower than the potential of the anode 103. In the present case, this is the ground potential of the housing of the object chamber 120. In this way, the electrons of the primary electron beam can be decelerated to a desired energy that is required for the examination of the object 125.

[0065] The object 125 and the individual electrode 112 can also be at different potentials and at potentials other than ground potential. This makes it possible to adjust the location of the deceleration of the primary electron beam relative to the object 125. For example, if the deceleration occurs quite close to the object 125, imaging errors become smaller.

[0066] The further SEM 100 further comprises a guidance system in the form of a deflection device, which comprises a first guidance device in the form of a first deflection device 130 and a second guidance device in the form of a second deflection device 115. The first deflection device 130 is arranged on the source side within the first objective lens 107. The second deflection device 115, on the other hand, is arranged on the object side of the beam guide tube 104 within the first objective lens 107. The first deflection device 130 and the second deflection device 115 are crossed deflection devices. In other words, both the first deflection device 130 and the second deflection device 115 are designed to deflect the primary electron beam in two non-parallel directions that are oriented perpendicular to the direction of the optical axis OA of the further SEM 100.For example, the first deflection device 130 and / or the second deflection device 115 is / are a magnetic deflection device. In particular, the first deflection device 130 and / or the second deflection device 115 has / have, for example, four air-core coils arranged around the optical axis OA of the further SEM 100. Additionally or alternatively, it is provided that the first deflection device 130 and / or the second deflection device 115 is / are an electrostatic deflection device. In particular, the first deflection device 130 and / or the second deflection device 115 has / have, for example, four electrodes arranged around the optical axis OA of the SEM 100, to which different electrostatic potentials can be applied. The primary electron beam is deflected by means of the first deflection device 130 and the second deflection device 115 and can be scanned over the object 125.The electrons of the primary electron beam interact with object 125. The interaction generates interaction particles, which are then detected. Specifically, electrons are emitted as interaction particles from the surface of object 125—so-called secondary electrons—or electrons of the primary electron beam are scattered back—so-called backscattered electrons.

[0067] A detector system is arranged in the beam guide tube 104, comprising a first detector 116 and a second detector 117 for detecting the secondary electrons and / or the backscattered electrons. 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 in the beam guide tube 104. The first detector 116 and the second detector 117 are offset from one another in the direction of the optical axis OA of the SEM 100. Both the first detector 116 and the second detector 117 have an opening 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 beam guide tube 104, and the optical axis OA of the SEM 100 runs through the respective opening.

[0068] The second detector 117 is primarily used to detect secondary electrons. The secondary electrons initially have low kinetic energy and can move in any direction when they exit the object 125. Due to the strong extraction field emanating from the tubular electrode 113, the secondary electrons are accelerated toward the first objective lens 107. The secondary electrons enter the first objective lens 107 approximately parallel. The beam diameter of the secondary electrons remains small in the first objective lens 107. The first objective lens 107 exerts a strong influence on the secondary electrons, creating a comparatively short focus of secondary electrons with sufficiently steep angles to the optical axis OA so that the secondary electrons disperse after the focus and impinge on the active surface of the second detector 117.Electrons scattered back by object 125, i.e., backscattered electrons that have a relatively high kinetic energy upon exiting object 125 compared to the secondary electrons, are only detected to a small extent by the second detector 117. The high kinetic energy and the angles of the backscattered electrons with respect to the optical axis OA upon exiting object 125 result in a beam waist, i.e., a beam region with a minimal diameter, of the backscattered electrons being located near the second detector 117. A large portion of the backscattered electrons passes through the opening of the second detector 117. Therefore, the first detector 116 is essentially used to detect the backscattered electrons.

[0069] In a further embodiment of the further SEM 100, the first detector 116 can additionally comprise a counter-field grating 116A. The counter-field grating 116A is arranged on the side of the first detector 116 facing the object 125. The counter-field grating 116A has a negative potential compared to the potential of the beam guide tube 104, so that only backscattered electrons with high kinetic energy pass through the counter-field grating 116A to the first detector 116. Additionally or alternatively, the second detector 117 comprises a further counter-field grating, which is designed in the same way as the aforementioned counter-field grating 116A of the first detector 116 and has an analogous function.

[0070] In addition, the further SEM 100 comprises a chamber detector 119 in the object chamber 120, for example an Everhart-Thornley detector or an ion detector, which may have a detection surface coated with light-shielding metal.

[0071] The detection signals generated by the first detector 116, the second detector 117 and the chamber detector 119 are used to generate one or more images of the surface of the object 125.

[0072] It should be expressly noted that the apertures of the first aperture unit 108 and the second aperture unit 109, as well as the apertures of the first detector 116 and the second detector 117, are exaggerated. The apertures of the first detector 116 and the second detector 117 have an extension perpendicular to the optical axis OA in the range of 0.5 mm to 5 mm. They are, for example, circular in shape and have a diameter perpendicular to the optical axis OA in the range of 1 mm to 3 mm.

[0073] In the embodiment shown here, the second aperture unit 109 is designed as a pinhole unit and is provided with a second aperture 118 for the passage of the primary electron beam. The second aperture 118 has an extension in the range of 5 µm to 500 µm, for example 35 µm. Alternatively, in a further embodiment, the second aperture unit 109 is provided with a plurality of apertures that are mechanically displaceable relative to the primary electron beam or that can be reached by the primary electron beam by means of electrical and / or magnetic deflection elements. The second aperture unit 109 can be 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 to 10 -12 hPa), from a second area which has a high vacuum (10 -3 hPa to 10 -7hPa). The second region is the medium pressure region of the beam guide tube 104, which leads to the object chamber 120.

[0074] The object chamber 120 is under vacuum. To generate the vacuum, a pump (not shown) is arranged on the object chamber 120. In the Fig. In the embodiment shown in Figure 2, the object 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 includes only pressures greater than 10 -3 hPa. The object chamber 120 is vacuum-tight to ensure these pressure ranges.

[0075] The object holder 114 is arranged on a object stage 122. The object stage 122 is configured to be movable in three mutually perpendicular directions, namely an x-direction (first stage axis), a y-direction (second stage axis), and a z-direction (third stage axis). Furthermore, the object stage 122 can be rotated about two mutually perpendicular rotation axes (stage rotation axes). The invention is not limited to the object stage 122 described above. Rather, the object stage 122 can have additional translation axes and additional rotation axes along or around which the object stage 122 can move.

[0076] The further SEM 100 further comprises a third detector 121 arranged in the specimen chamber 120. In particular, the third detector 121 is arranged behind the specimen stage 122 along the optical axis OA, as viewed from the electron source 101. The specimen stage 122 and thus the specimen holder 114 can be rotated so that the primary electron beam can impinge on the specimen 125 arranged on the specimen holder 114. When the primary electron beam passes through the specimen 125 to be examined, the electrons of the primary electron beam interact with the material of the specimen 125 to be examined. The electrons that pass through the specimen 125 to be examined are detected using the third detector 121.

[0077] A radiation detector 500 is arranged on the object chamber 120 and detects interaction radiation (for example, X-rays and / or cathodoluminescence light) generated when the primary electron beam strikes the object 125. The radiation detector 500, the first detector 116, the second detector 117, and the chamber detector 119 are connected to a control device 123, which includes a monitor 124. The third detector 121 is also connected to the control device 123. For the sake of clarity, this is not shown. The control device 123 processes detection signals generated by the first detector 116, the second detector 117, the chamber detector 119, the third detector 121, and / or the radiation detector 500 and displays them in the form of images on the monitor 124.

[0078] The first deflection device 130 and the second deflection device 115 are connected to the control device 123. In particular, the first deflection device 130 is connected to the control device 123 by a first signal connection 800. The first signal connection 800 can be a physical connection such as a connection line and / or a wireless connection such as a radio communication system and / or a wireless local area network. The second deflection device 115 is connected to the control device 123 by a second signal connection 801. The second signal connection 801 can be a physical connection such as a connection line and / or a wireless connection such as a radio communication system and / or a wireless local area network.

[0079] The control device 123 further comprises a database 126 in which data is stored and from which data is read. Furthermore, the control device 123 is connected to other units of the further SEM 100. This is not shown in detail for reasons of clarity.

[0080] The control device 123 of the further SEM 100 comprises a processor 127. A computer program product comprising program code is loaded into the processor 127. When the program code is executed, a method for operating the further SEM 100 is executed. This is explained in more detail below.

[0081] In the further SEM 100, it is possible to set a distance A by means of the control device 123 of the further SEM 100. The distance A is given either (a) by an object distance between the individual electrode 112 of the further SEM 100 and the object 125 or (b) by a focal plane distance between the individual electrode 112 of the further SEM 100 and a focal plane of the first objective lens 107. The aforementioned distance A according to case (a) or case (b) is also referred to as the working distance. For example, in case (a), the distance A is set by moving the object stage 122 and / or moving the first objective lens 107 with a movement device 25. For example, in case (b), the distance A is set by varying an excitation of the first objective lens 107 along the optical axis OA of the further SEM 100.

[0082] 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. On the one hand, the combination device 200 has the further SEM 100, as already shown in Fig. 2, but without the sample chamber 120. Rather, the further SEM 100 is arranged on an object chamber 201. The object chamber 201 is under vacuum. To generate the vacuum, a pump (not shown) is arranged on the object chamber 201. In the Fig. In the embodiment shown in Figure 3, the object 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 includes only pressures greater than 10 -3 hPa. The object chamber 201 is vacuum-tight to ensure these pressure ranges.

[0083] The chamber detector 119 is arranged in the object chamber 201. The chamber detector 119 is designed, for example, as an Everhart-Thornley detector or an ion detector. The chamber detector 119 can have a detection surface coated with light-shielding metal. Furthermore, the third detector 121 is arranged in the object chamber 201.

[0084] The further SEM 100 generates a first particle beam, namely the primary electron beam already described above, and has the optical axis already mentioned above, which is Fig. 3 is provided with the reference numeral 709 and is referred to below as the first beam axis. Secondly, the combination device 200 is provided with an ion beam device 300, which is also arranged on the object chamber 201. The ion beam device 300 also has an optical axis which is Fig. 3 is provided with the reference number 710 and is referred to below as the second beam axis.

[0085] The further SEM 100 is arranged vertically to the object chamber 201. In contrast, the ion beam device 300 is arranged at an angle of approximately 0° to 90° to the SEM 100. In Fig. 3 shows an arrangement of approximately 50°. The ion beam device 300 comprises a second beam generator in the form of an ion beam generator 301. The ion beam generator 301 is used to generate ions that form 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 predeterminable potential. The second particle beam then passes through an ion optics system of the ion beam device 300, which includes a condenser lens 303 and a second objective lens 304. Finally, the second objective lens 304 generates an ion probe that is focused on the object 125 arranged on an object holder 114. The object holder 114 is arranged on an object stage 122.

[0086] An adjustable or selectable aperture unit 306 and a guidance system are arranged above the second objective lens 304 (i.e., in the direction of the ion beam generator 301). The guidance system comprises a first guidance device in the form of a first deflection device 307 and a second guidance device in the form of a second deflection device 308. The first deflection device 307 is arranged on the source side within the second objective lens 304. The second deflection device 308, on the object side, is arranged within the second objective lens 304. The first deflection device 307 and the second deflection device 308 are crossed deflection devices. In other words, both the first deflection device 307 and the second deflection device 308 are designed to deflect the ion beam in two non-parallel directions that are oriented perpendicular to the direction of the optical axis in the form of the second beam axis 710 of the ion beam device 300.For example, the first deflection device 307 and / or the second deflection device 308 are / is (a) magnetic deflection device(s). In particular, the first deflection device 307 and / or the second deflection device 308 can, for example, have four air-core coils arranged around the optical axis in the form of the second beam axis 710 of the ion beam device 300. Additionally or alternatively, the first deflection device 307 and / or the second deflection device 308 are / is (a) electrostatic deflection device. In particular, the first deflection device 307 and / or the second deflection device 308 can, for example, have four electrodes arranged around the optical axis in the form of the second beam axis 710 of the ion beam device 300, to which different electrostatic potentials can be applied.By means of the first deflection device 307 and the second deflection device 308, the ion beam is deflected and can be scanned over the object 125.

[0087] As explained above, the object holder 114 is arranged on the object table 122. In the Fig. In the embodiment shown in Figure 3, the stage 122 is designed to move in three mutually perpendicular directions, namely an x-direction (first stage axis), a y-direction (second stage axis), and a z-direction (third stage axis). Furthermore, the stage 122 can be rotated about two mutually perpendicular rotation axes (stage rotation axes).

[0088] The distances between the individual units of the combination device 200 are in Fig. 3 is exaggerated in order to better illustrate the individual units of the combination device 200.

[0089] A radiation detector 500 for detecting interaction radiation, such as X-rays and / or cathodoluminescent light, is arranged on the specimen chamber 201. The radiation detector 500 is connected to a control device 123, which includes a monitor 124.

[0090] The control device 123 processes detection signals received from the first detector 116 (not shown in Fig. 3), the second detector 117 (not shown in Fig. 3), the chamber detector 119, the third detector 121 and / or the radiation detector 500, and displays them in the form of images on the monitor 124.

[0091] The control device 123 further comprises a database 126 in which data is stored and from which data is read. Furthermore, the control device 123 is connected by the first signal connection 800 (in Fig. 3 not shown) with the first deflection device 130 and through the second signal connection 801 (in Fig. 3) is connected to the second deflection device 115. In addition, the control device 123 is connected to the first deflection device 307 by a first signal connection and to the second deflection device 308 by a second signal connection.

[0092] The control device 123 of the combination device 200 comprises a processor 127. A computer program product with program code is loaded into the processor 127. Upon execution of the program code, a method for operating the combination device 200 is executed. This will be explained in more detail below.

[0093] It is also possible to set working distances with the combination device 200. For example, with the further SEM 100, it is possible to set a distance A1 via the control device 123. The distance A1 is given either (a) by an object distance between an outer boundary of the first objective lens 107 of the further SEM 100 and the object 125 or (b) by a focal plane distance between the outer boundary of the first objective lens 107 of the further SEM 100 and a focal plane of the first objective lens 107. The aforementioned distance A1 according to case (a) or case (b) is also referred to as the working distance. For example, in case (a), the distance A1 is set by moving the object stage 122 and / or moving the first objective lens 107 with the movement device 25. For example, in case (b), the distance A1 is adjusted by varying an excitation of the first objective lens 107 along the first beam axis 709 of the further SEM 100.Furthermore, it is possible to adjust a distance A2 using the control device 123. The distance A2 is given either by (a) an object distance between an outer boundary of the second objective lens 304 of the ion beam device 300 and the object 125 or (b) a focal plane distance between the outer boundary of the second objective lens 304 of the ion beam device 300 and a focal plane of the second objective lens 304. The aforementioned distance A2 according to case (a) or case (b) is also referred to as a working distance. For example, in case (a), the distance A2 is adjusted by moving the object stage 122 and / or moving the second objective lens 304 with a movement device 25. For example, in case (b), the distance A2 is adjusted by varying an excitation of the second objective lens 304 along the second beam axis 710 of the ion beam device 300.

[0094] In the following, we will now take a closer look at the object stage 122 of the Fig. 2 shown further SEM 100 and the one in Fig. 3 shown combination device 200. The object table 122 is designed as a movable object table, which in Fig. 4 and Fig. 5 is shown schematically. The following explanation applies accordingly with regard to the object stage 19 of the SEM 100 according to Fig. 1.

[0095] It should be noted that the invention is not limited to the stage 122 described herein. Rather, the invention may include any movable stage suitable for the invention.

[0096] The object holder 114 is arranged on the object stage 122. The object stage 122 has movement elements that ensure movement of the object stage 122 so that an area of ​​interest on the object 125 can be examined, for example, with a particle beam. The movement elements are in Fig. 4 and Fig. 5 are shown schematically and are explained below.

[0097] The object stage 122 has a first movement element 600, which is arranged, for example, on a housing 601 of the object chamber 120 or 201 in which the object stage 122 is arranged. The first movement element 600 enables movement of the object stage 122 along the z-axis (third stage axis). Furthermore, a second movement element 602 is provided. The second movement element 602 enables rotation of the object stage 122 about a first stage rotation axis 603, which is also referred to as the tilt axis. This second movement element 602 serves to tilt the object 125 about the first stage rotation axis 603, wherein the object 125 is arranged on the object holder 114.

[0098] A third movement element 604 is arranged on the second movement element 602. This third movement element 604 is designed as a guide for a carriage and ensures that the object stage 122 is movable in the x-direction (first stage axis). The aforementioned carriage is in turn a further movement element, namely a fourth movement element 605. The fourth movement element 605 is designed such that the object stage 122 can be moved in the y-direction (second stage axis). For this purpose, the fourth movement element 605 has a guide in which a further carriage is guided, on which the object holder 114 is arranged. The object holder 114 has a fifth movement element 606, which enables rotation of the object holder 114 about a second stage rotation axis 607. The second stage rotation axis 607 is aligned perpendicular to the first stage rotation axis 603.

[0099] Based on the arrangement described above, the object stage 122 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 stage 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 stage rotation axis 607).

[0100] In a further embodiment (not shown), it is provided to arrange further movement elements on the object table 122 so that movements along further translation axes and / or about further rotation axes are enabled.

[0101] As it is in Fig. As shown in Figure 5, each of the above-mentioned moving elements is connected to a drive unit M1 to M5 in the form of a motor. The first moving element 600 is connected to a first drive unit M1 and is driven based on a drive force provided by the first drive unit M1. The second moving element 602 is connected to a second drive unit M2, which drives the second moving element 602. The third moving element 604 is connected to a third drive unit M3. The third drive unit M3 provides a drive force for driving the third moving element 604. The fourth moving element 605 is connected to a fourth drive unit M4, wherein the fourth drive unit M4 drives the fourth moving element 605. Furthermore, the fifth moving element 606 is connected to a fifth drive unit M5.The fifth drive unit M5 provides a driving force that drives the fifth moving element 606.

[0102] The aforementioned drive units M1 to M5 can be designed, for example, as stepper motors and are controlled by a drive control unit 608. Each drive unit M1 to M5 can be supplied with a supply current by the drive control unit 608 (as shown in Fig. 5). It should be expressly noted that the invention is not limited to movement by stepper motors. Rather, any drive unit suitable for the invention can be used as drive units, for example, brushless motors.

[0103] In the following, embodiments of the method according to the invention are described with respect to the SEM 100 according to Fig. 1. The method according to the invention can also be carried out with the further SEM 100 according to Fig. 2 and / or the combination device 200 according to Fig. 3 be carried out.

[0104] Fig. Figure 6 shows a schematic representation of a sequence of a first embodiment of the method according to the invention. The method according to the invention is used to operate the SEM 100.

[0105] Method step S1 comprises generating the primary electron beam by means of the beam generator 1 of the SEM 100. Method step S2 comprises guiding the primary electron beam to the object 15. In particular, the primary electron beam is guided away from the optical axis 20 of the SEM 100 by means of the first deflection device 9 at a first angle to the optical axis 20. Furthermore, the primary electron beam is guided by means of the second deflection device 12, wherein the primary electron beam is guided to the optical axis 20 at a second angle to the optical axis 20 such that the primary electron beam is guided to first positions on a surface of the object 15. The first positions are arranged along a first geometric shape on the surface of the object 15. The first geometric shape can be any geometric shape. Method step S3 comprises guiding the primary electron beam to the object 15.In particular, the primary electron beam is guided away from the optical axis 20 of the SEM 100 by means of the first deflection device 9 at a third angle with respect to the optical axis 20. Furthermore, the primary electron beam is guided by means of the second deflection device 12, wherein the primary electron beam is guided to the optical axis 20 at a fourth angle with respect to the optical axis 20, such that the primary electron beam is guided to second positions on the surface of the object 15. The second positions are arranged along a second geometric shape on the surface of the object 15. The second geometric shape can be any geometric shape.

[0106] Method step S4 provides a first guidance signal for guiding the primary electron beam using the control device 123 of the SEM 100. The first guidance signal is delivered from the control device 123 to the first deflection device 9 using the first signal connection 800 between the control device 123 and the first deflection device 9. As mentioned above, the first signal connection 800 may be a physical connection such as a connecting line and / or a wireless connection such as a radio communication system and / or a wireless local area network.

[0107] Method step S5 provides a second guidance signal for guiding the primary electron beam using the controller 123 of the SEM 100. The second guidance signal is provided from the controller 123 to the second deflection device 12 using the second signal connection 801 between the controller 123 and the second deflection device 12. As mentioned above, the second signal connection 801 may be a physical connection such as a connecting line and / or a wireless connection such as a radio communication system and / or a wireless local area network.

[0108] To guide the primary electron beam to the first geometric shape, the first guide signal and the second guide signal are provided as a function of a first distance from a center point arranged on the surface of the object 15 to the first geometric shape. The first guide signal and the second guide signal are used to guide the primary electron beam along the first geometric shape. The first distance can be a distance of the center point to one of the first positions arranged on the first geometric shape. For example, the distance can be the shortest distance of all distances of the center point to the first positions arranged on the first geometric shape.

[0109] To guide the primary electron beam to the second geometric shape, the first guide signal and the second guide signal are provided as a function of a second distance from the center point arranged on the surface of the object 15 to the second geometric shape. The first guide signal and the second guide signal are used to guide the primary electron beam along the second geometric shape. The second distance can be a distance from the center point to one of the second positions arranged on the second geometric shape. For example, the distance can be the shortest distance of all distances from the center point to the second positions arranged on the second geometric shape.

[0110] According to the invention, guiding the primary electron beam along the first geometric shape and / or along the second geometric shape is faster in time than guiding the primary electron beam from the first geometric shape to the second geometric shape.

[0111] A method step S6 comprises imaging, analyzing, and / or processing the object 15 with the primary electron beam at the first positions and / or at the second positions. Reference is made to the above explanations, which also apply here.

[0112] An embodiment of the method according to the invention uses circular shapes or full circles as the first geometric shape and / or second geometric shape. Fig. 7 shows an embodiment of the first geometric shape and the second geometric shape. Reference numeral 900 denotes the first geometric shape in the shape of a first full circle. Reference numeral 901 denotes the second geometric shape in the shape of a second full circle. The first positions FP11 to FP110 are arranged along the first geometric shape 900 on the surface 902 of the object 15. It should be expressly noted that the number of first positions arranged along the first geometric shape 900 is not limited to the first positions FP11 to FP110. Rather, any number of first positions suitable for the invention can be used. The second positions FP21 to FP210 are arranged along the second geometric shape 901 on the surface 902 of the object 15.It should be expressly noted that the number of second positions arranged along the second geometric shape 901 is not limited to the second positions FP21 to FP210. Rather, any number of second positions suitable for the invention can be used. The first geometric shape 900 is determined (i) by a center point CP arranged on the surface 902 of the object 15 and (ii) by a first radius R1 extending from the center point CP along the surface 902 of the object 15. The second geometric shape 901 is determined by the center point CP and by a second radius R2 extending from the center point CP along the surface 902 of the object 15.

[0113] With respect to the first geometric shape 900 in the form of a first full circle, method steps S4 and S5 comprise providing the first guide signal and the second guide signal as a function of the first radius R1 for guiding the primary electron beam along the first geometric shape 900. With respect to the second geometric shape 901 in the form of a second full circle, method steps S4 and S5 comprise providing the first guide signal and the second guide signal as a function of the second radius R2 for guiding the primary electron beam along the second geometric shape 901.

[0114] As mentioned above, the first geometric shape 900 and the second geometric shape 901 may be any geometric shapes. Therefore, a further embodiment of the method according to the invention additionally or alternatively comprises (i) using a polygon as the first geometric shape 900; and (ii) using a polygon as the second geometric shape 901. Fig. 8 shows such an embodiment of the first geometric shape and the second geometric shape. Reference numeral 900A denotes the first geometric shape in the form of a first polygon, for example a square. Reference numeral 901A denotes the second geometric shape in the form of a second polygon, for example a square. The first positions FP11 to FP14 are arranged along the first geometric shape 900A on the surface 902 of the object 15. It should be expressly noted that the number of first positions arranged along the first geometric shape 900A is not limited to the first positions FP11 to FP14. Rather, any number of first positions suitable for the invention can be used. The second positions FP21 to FP24 are arranged along the second geometric shape 901A on the surface 902 of the object 15.It should be expressly noted that the number of second positions arranged along the second geometric shape 901A is not limited to the second positions FP21 to FP24. Rather, any number of second positions suitable for the invention can be used. The first geometric shape 900A is determined (i) by the center point CP arranged on the surface 902 of the object 15, and (ii) by a first distance D1 between the center point CP and one of the first positions FP11 to FP14, for example, the first position FP14. The second geometric shape 901A is determined (i) by the center point CP arranged on the surface 902 of the object 15, and (ii) by a second distance D2 extending from the center point CP to one of the second positions FP21 to FP24, for example, FP24.

[0115] Fig. 9 shows a schematic representation of the control device 123 of the SEM 100 according to Fig. 1. The control device 123 is connected to a first amplifier 803 via the first signal connection 800. The first amplifier 803 is also connected to the first deflection device 9 via the first signal connection 800. Furthermore, the control device 123 is connected to a second amplifier 804 via the second signal connection 801. The second amplifier 804 is also connected to the second deflection device 12 via the second signal connection 801. In addition, the control device 123 is connected to the objective lens 10 via a third signal connection 802. The first signal connection 800, the second signal connection 801, and / or the third signal connection 802 can be a physical connection such as a connecting line and / or a wireless connection such as a radio communication system and / or a wireless local area network.

[0116] As mentioned above, the first guide signal and the second guide signal are provided by the controller 123. As shown in Fig. As shown in Figure 9, the controller 123 is connected to the first amplifier 803 to supply the first guide signal to the first deflection device 9. The first amplifier 803 is configured to increase or decrease the first guide signal using a first gain factor. Furthermore, the controller 123 is connected to the second amplifier 804 to supply the second guide signal to the second deflection device 12. The second amplifier 804 is configured to increase or decrease the second guide signal using a second gain factor.

[0117] As is particularly the case in Fig. 7, the first radius R1 is smaller than the second radius R2. The ratio of the first gain factor to the second gain factor is higher when guiding the primary electron beam along the second geometric shape 901 than when guiding the primary electron beam along the first geometric shape 900. The aforementioned gain factors are selected depending on the first radius R1 and the second radius R2.

[0118] A further embodiment of the method according to the invention additionally or alternatively provides for the first guide signal to be used as the second guide signal. Furthermore, a further embodiment of the method according to the invention additionally or alternatively provides that the first amplification factor is constant, while the second amplification factor is different when guiding the primary electron beam along the second geometric shape 901 and when guiding the primary electron beam along the first geometric shape 900. Alternatively, the second amplification factor is constant, while the first amplification factor is different when guiding the primary electron beam along the second geometric shape 901 and when guiding the primary electron beam along the first geometric shape 900. The aforementioned embodiments can be used in particular when the first guide signal is used as the second guide signal.

[0119] As it is in Fig. 9, the control device 123 is connected to the objective lens 10 by means of the third signal connection 802. A further embodiment of the method according to the invention can be carried out by the SEM 100, which has the Fig. 9. The further embodiment of the method according to the invention is shown in Fig. 10. The Fig. 10 further embodiment of the method according to the invention is based on the Fig. 6 illustrated embodiment of the method according to the invention. Reference is made to the explanations given above, which also apply here. In contrast to the embodiment according to Fig. 6 shows the embodiment according to Fig. 10 additional method steps, namely method steps S5A and S5B. For example, method steps S5A and S5B are executed after method step S5 and before method step S6. In method steps S5A and S5B, control signals are provided which are used to control the objective lens 10 as a function of (i) the first distance of the center point CP to the first geometric shape 900 and (ii) the second distance of the center point CP to the second geometric shape 901. For example, the first distance is the first radius R1 and the second distance is the second radius R2 (see Fig. 7). Alternatively, the first distance can be the first distance D1 and the second distance can be the second distance D2 (see Fig. 8). In particular, in method step S5A, a first control signal is supplied to the objective lens 10 by the control device 123, wherein the first control signal is dependent on the first distance. The first control signal is used to focus the primary electron beam along the first geometric shape 900 or 900A. Furthermore, in method step S5B, a second control signal is supplied to the objective lens 10 by the control device 123, wherein the second control signal is dependent on the second distance. The second control signal is used to focus the primary electron beam along the second geometric shape 901 or 901A. Furthermore, the embodiment of the method shown in Fig. 10 may comprise (i) using an analog signal or a digital signal as the first control signal and (ii) using an analog signal or a digital signal as the second control signal. The first control signal and / or the second control signal are / is used to further reduce or avoid spherical aberrations. In particular, the first control signal may be used to direct the primary electron beam to the first positions FP11 to FP110 (as shown in Fig. 7) or FP11 to FP14 (as shown in Fig. 8). In a further embodiment of the Fig. 10, the first control signal may be in the form of a first analog signal for refocusing the primary electron beam to the first positions FP11 to FP110 (as shown in Fig. 7) or FP11 to FP14 (as shown in Fig. 8). In addition, the second control signal can be used to refocus the primary electron beam to the second positions FP21 to FP210 (as shown in Fig. 7) or FP21 to FP24 (as shown in Fig. 8). In a further embodiment of the device shown in Fig. 10, the second control signal may be in the form of a second analog signal for refocusing the primary electron beam to the second positions FP21 to FP210 (as shown in Fig. 7) or FP21 to FP24 (as shown in Fig. 8). Additionally or alternatively, the first control signal in the form of a first digital signal and / or the second control signal in the form of a second digital signal may be used to control a digital-to-analog converter used to generate a focus signal for the objective lens 10 of the SEM 100.

[0120] The embodiments of the Fig. 6 and Fig. The method shown in Figure 10 may additionally comprise at least one of the following steps: (i) using the second angle as the first angle; and (ii) using the fourth angle as the third angle. In other words, the first angle may be identical to the second angle. Furthermore, the third angle may be identical to the fourth angle.

[0121] The Fig. 6 and Fig. 10, the embodiments of the method may additionally include performing the rocking beam method at each of the first positions FP11 to FP110 (as shown in Fig. 7) or FP11 to FP14 (as shown in Fig. 8) and / or at each of the second positions FP21 to FP210 (as shown in Fig. 7) or FP21 to FP24 (as shown in Fig. 8). In other words, at each position of the first positions FP11 to FP110 (as in Fig. 7) or FP11 to FP14 (as shown in Fig. 8) the first angle has a first predeterminable value range and the third angle has a third predeterminable value range when the primary particle beam is directed to the respective position of the first positions FP11 to FP110 (as shown in Fig. 7) or FP11 to FP14 (as shown in Fig. 8). Additionally or alternatively, the second angle passes through a second predeterminable range of values ​​and the fourth angle passes through a fourth predeterminable range of values ​​when the primary electron beam is guided to the respective position of the second positions FP21 to FP210 (as shown in Fig. 7) or FP21 to FP24 (as shown in Fig. 8). Each of the aforementioned predeterminable value ranges can comprise angles in the range from 0° to 90°, wherein the boundaries can be contained in the aforementioned predeterminable value ranges.

[0122] All of the above-mentioned and subsequent embodiments of the method according to the invention are not limited to the explained sequence of method steps. The invention also encompasses other sequences of method steps that are suitable for achieving the object of the invention. Additionally or alternatively, the method according to the invention also provides for parallel execution of at least two method steps. Furthermore, the above-mentioned and subsequent embodiments of the method according to the invention are not limited to the entirety of all method steps mentioned above or below. In particular, it is provided that in further embodiments, one or more of the method steps mentioned above or below are omitted.

[0123] The features of the invention disclosed in the present description, the drawings, and the claims may be essential, both individually and in any combination, for the realization of the invention in its various embodiments. The invention is not limited to the described embodiments. It may be modified within the scope of the claims and taking into account the specialist knowledge of those skilled in the art. Reference symbol 1 beam generator 2 Extraction electrode 3 Control electrode 4 Anode 5 first condenser lens 6 second condenser lens 7 aperture unit 8 second detector unit 9 first guide device / first deflection device 10 objective lens 11 Ring-shaped coil 12 second guide device / second deflection device 13 Object Chamber 14 first detector unit 15 objects 16 Object level 17 compression damper bracket 18 aperture 19 movable stage 20 optical axis 21 Beam guide tube 22 Pole piece 23 Pole piece gap 25 Movement device 100 SEM 101 Electron source 102 Extraction electrode 103 Anode 104 Beam guide tube 105 first condenser lens 106 second condenser lens 107 first objective lens 108 first aperture unit 108A first aperture 109 second aperture unit 110 pole pieces 111 Coil 112 single electrode 113 Tubular electrode 114 object holders 115 second guide device / second deflection device 116 first detector 116A opposing field grid 117 second detector 118 second aperture 119 Chamber detector 120 Object Chamber 121 third detector 122 Object table 123 Control device 124 monitors 125 objects 126 database 127 processor 130 first guidance device / first deflection device 200 combination device 201 Object Chamber 300 ion beam device 301 ion beam generator 302 Extraction electrode in ion beam device 303 Condenser lens 304 second objective lens 306 adjustable or selectable aperture unit 307 first guidance device / first deflection device 308 second guide device / second deflection device 500 radiation detector 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 drive control unit 709 first beam axis 710 second beam axis 800 first signal connection 801 second signal connection 802 third signal connection 803 first amplifier 804 second amplifier 900 first geometric form 900A first geometric shape 901 second geometric shape 901A second geometric shape 902 Surface of the object A distance A1 distance A2 distance CP center point D1 first distance D2 second distance FP11 to FP110 first positions FP21 to FP210 second positions M1 first drive unit M2 second drive unit M3 third drive unit M4 fourth drive unit M5 fifth drive unit OA optical axis R1 first radius R2 second radius S1 to S6 process steps S5A Process step S5B Process step QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 11 2016 005 577 B4

[0012] US 2020 / 0013581 A1

[0012]

Claims

[1] A method for operating a particle beam device (100, 200, 300) for processing, imaging and / or analyzing an object (15, 125), comprising: - generating a particle beam with a beam generator (1, 101, 301) of the particle beam device (100, 200, 300), wherein the particle beam comprises charged particles, - guiding the particle beam using a first guiding device (9, 130, 307), wherein the particle beam is guided away from an optical axis (20, 709, 710, OA) of the particle beam device (100, 200, 300) at a first angle with respect to the optical axis (20, 709, 710, OA), and guiding the particle beam using a second guiding device (12, 115, 308), wherein the particle beam is guided to the optical axis (20, 709, 710, OA) at a second angle with respect to the optical axis (20, 709, 710, OA) such that the particle beam is guided to first positions (FP11 to FP110) on a surface (902) of the object (15, 125), wherein the first positions (FP11 to FP110) are along a first geometric shape (900, 900A) are arranged on the surface (902) of the object (15,125), - guiding the particle beam using the first guiding device (9, 130, 307), wherein the particle beam is guided away from the optical axis (20, 709, 710, OA) at a third angle with respect to the optical axis (20, 709, 710, OA), and guiding the particle beam using the second guiding device (12, 115, 308), wherein the particle beam is guided to the optical axis (20, 709, 710, OA) at a fourth angle with respect to the optical axis (20, 709, 710, OA) such that the particle beam is guided to second positions (FP21 to FP210) on the surface (902) of the object (15, 125), wherein the second positions (FP21 to FP210) are along a second geometric shape (901, 901A) on the surface (902) of the object (15, 125), - providing a first guide signal for guiding the particle beam using a control device (123), wherein the first guide signal is supplied to the first guide device (9, 130, 307) using a first signal connection (800) between the control device (123) and the first guide device (9, 130, 307), - providing a second guide signal for guiding the particle beam using the control device (123), wherein the second guide signal is supplied to the second guide device (12, 115, 308) using a second signal connection (801) between the control device (123) and the second guide device (12, 115, 308), - Providing the first guide signal and the second guide signal as a function of a first distance (R1, D1) of a center point (CP) arranged on the surface (902) of the object (15, 125) to the first geometric shape (900, 900A) for guiding the particle beam along the first geometric shape (900, 900A), - Providing the first guide signal and the second guide signal as a function of a second distance (R2, D2) of the center point (CP) to the second geometric shape (901, 901A) for guiding the particle beam along the second geometric shape (901, 901A), and wherein guiding the particle beam along the first geometric shape (900, 900A) and / or along the second geometric shape (901, 901A) is faster in time than guiding the particle beam from the first geometric shape (900, 900A) to the second geometric shape (901, 901A). [2] The method of claim 1, further comprising at least one of the following: (i) using a circular shape as the first geometric shape (900, 900A); (ii) using a circular shape as the second geometric shape (901, 901A); (iii) using a first circle as the first geometric shape (900, 900A); (iv) Using a second circle as the second geometric shape (901, 901A). [3] The method of claim 2, wherein the first geometric shape (900, 900A) is determined by the center point (CP) and by a first radius (R1) extending from the center point (CP) along the surface (902) of the object (15, 125), and wherein the second geometric shape (901, 901A) is determined by the center point (CP) and by a second radius (R2) extending from the center point (CP) along the surface (902) of the object (15, 125), the method further comprising: - providing the first guide signal and the second guide signal as a function of the first radius (R1) for guiding the particle beam along the first geometric shape (900, 900A), and - Providing the first guide signal and the second guide signal as a function of the second radius (R2) for guiding the particle beam along the second geometric shape (901, 901A). [4] A method according to any one of the preceding claims, further comprising at least one of the following steps: (i) using a polygon as the first geometric shape (900, 900A); (ii) Using a polygon as the second geometric shape (901, 901A). [5] A method according to any one of the preceding claims, wherein the first distance (R1, D1) is smaller than the second distance (R2, D2), and wherein the method further comprises: - providing the first control signal with a first gain factor of a first amplifier (803) by the control device (123), and - providing the second guide signal with a second amplification factor of a second amplifier (804) by the control device (123), wherein the ratio of the first amplification factor to the second amplification factor is higher when guiding the particle beam along the second geometric shape (901, 901A) than when guiding the particle beam along the first geometric shape (900, 900A). [6] A method according to any one of the preceding claims, wherein the first guide signal is used as the second guide signal. [7] A method according to any one of the preceding claims, further comprising: - supplying a first control signal by the control device (123) to an objective lens (10, 107, 304) of the particle beam device (100, 200, 300) as a function of the first distance (R1, D1) for focusing the particle beam along the first geometric shape (900, 900A), and - Supplying a second control signal by the control device (123) to the objective lens (10, 107, 304) as a function of the second distance (R2, D2) for focusing the particle beam along the second geometric shape (901, 901A). [8] The method of claim 7, further comprising one of the following steps: - Using an analog signal or a digital signal as the first control signal; - Using an analog signal or a digital signal as a second control signal. [9] A method according to any one of the preceding claims, further comprising at least one of the following steps: - Using the second angle as the first angle; - Using the fourth angle as the third angle. [10] Computer program product comprising program code loadable into a processor (127) and which, when executed, controls a particle beam device (100, 200, 300) such that a method according to at least one of the preceding claims is carried out. [11] Particle beam device (100, 200, 300) for processing, imaging and / or analyzing an object, comprising: - at least one beam generator (1, 101, 301) for generating a particle beam with charged particles, - at least one first guiding device (9, 130, 307) for guiding the particle beam, - at least one second guiding device (12, 115, 308) for guiding the particle beam, - at least one control device (123) for providing a first guide signal and a second guide signal for guiding the particle beam, - at least one first signal connection (800) arranged between the control device (123) and the first guide device (9, 130, 307), - at least one second signal connection (801) arranged between the control device (123) and the second guide device (12, 115, 308), and - at least one processor (127) arranged in or on the control device (123) and into which a computer program product according to claim 10 is loaded. [12] Particle beam device (100, 200, 300) according to claim 11, further comprising at least one scanning device (9, 12, 115, 130, 307, 308) for guiding the particle beam over the object (15, 125), wherein the scanning device (9, 12, 115, 130, 307, 308) comprises the first guiding device (9, 130, 307) and the second guiding device (12, 115, 308). [13] Particle beam device (100, 200, 300) according to claim 11 or 12, further comprising at least one detector unit (8, 14, 116, 117, 119, 121, 500) for detecting interaction particles and / or interaction radiation resulting from an interaction of the particle beam with the object (15, 125). [14] Particle beam device (100, 200, 300) according to one of claims 11 to 13, further comprising at least one objective lens (10, 107, 304) for focusing the particle beam onto the object (15, 125). [15] Particle beam device (200) according to claim 14, wherein the beam generator (101) is a first beam generator, wherein the particle beam is a first particle beam comprising first charged particles, wherein the objective lens (107) is a first objective lens for focusing the first particle beam onto the object (125), and wherein the particle beam device (200) further comprises: - at least one second beam generator (301) for generating a second particle beam comprising second charged particles; and - at least one second objective lens (304) for focusing the second particle beam onto the object (125). [16] Particle beam device (100, 200, 300) according to one of claims 11 to 15, further comprising: a first amplifier (803) connected to the first guide device (9, 130, 307) and a second amplifier (804) connected to the second guide device (12, 115, 308). [17] Particle beam device (100, 200, 300) according to one of claims 11 to 16, wherein the particle beam device (100, 200, 300) is an electron beam device and / or an ion beam device.

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