Method of generating corrected image, computer program product and particle beam apparatus

Abstract

The invention relates to a method for generating a corrected image of an object. The method includes directing a particle beam over a scanning region of an object; detecting interaction particles and / or interaction radiation; generating a plurality of images of the scanning area; defining an interference function; calculating actual scanning points in the scanning area by means of an interference function; calculating an expected detection signal at the expected scanning point; generating a desired image of the scanning area for the plurality of images; comparing the generated desired images; testing (i) whether a quality metric dependent on the interference parameter and the subtraction signal is less than or equal to a predeterminable threshold and / or (ii) whether the quality metric does not deviate from or only slightly deviates from a predetermined quality metric; and, if the condition (s) are present, one of the following steps is performed: (a) defining a corrected image by selecting one of the desired images as a corrected image; (b) compute the corrected image or (c) may be used in the guidance device to record the corrected image by maintaining the interference function.

Description

Technical Field

[0001] The present invention relates to a method for generating a corrected image of an object using a particle beam device, a computer program product, and a particle beam device for performing the method. For example, the particle beam device takes the form of an electron beam device and / or an ion beam device. Background Art

[0002] Electron beam devices, in particular scanning electron microscopes (hereinafter also referred to as SEMs) and / or transmission electron microscopes (hereinafter also referred to as TEMs), are used to examine an object (hereinafter also referred to as a sample) in order to obtain information about its properties and behavior under certain conditions.

[0003] In an SEM, an electron beam (hereinafter also referred to as a primary electron beam) is generated by means of a beam generator, and the electron beam is focused on the object to be examined by means of a beam guiding system. The primary electron beam is guided over the surface of the object to be examined by means of a deflection device in the form of a scanning device. During this process, the electrons of the primary electron beam interact with the object to be examined. As a result of the interaction, in particular, electrons are emitted by the object (so-called secondary electrons), and the electrons of the primary electron beam are backscattered (so-called backscattered electrons). The secondary electrons and the backscattered electrons are detected and used for image generation. Thus, an image representation of the object to be examined is obtained. In addition, interaction radiation (for example, x-ray radiation or cathodoluminescence) is generated during the interaction, and this interaction radiation is detected by means of a detector and subsequently evaluated in order to analyze the object.

[0004] In the case of a TEM, a primary electron beam is likewise generated by means of a beam generator, and the primary electron beam is guided onto the object to be examined by means of a beam guiding system. The primary electron beam passes through the object to be examined. When the primary electron beam passes through the object to be examined, the electrons of the primary electron beam interact with the material of the object to be examined. The electrons passing through the object to be examined are imaged on a fluorescent screen or a detector (for example, a camera) by means of a system consisting of an objective lens and a projection unit. Here, the imaging can also be carried out in the scanning mode of the TEM. Generally, such a TEM is referred to as a STEM. Additionally, it is possible to provide for the detection of electrons backscattered at the object to be examined and / or secondary electrons emitted by the object to be examined using additional detectors 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. Thus, such a particle beam device can be used to examine an object by means of the SEM function and / or the STEM function.

[0006] In addition, particle beam apparatuses in the form of ion beam columns are known. Ions for machining an object are generated by means of an ion beam generator arranged in the ion beam column. For example, during machining, the material of the object is ablated or material is applied to the object, for example in the case of supplying a gas. In addition or as an alternative, the ions are used for imaging.

[0007] In addition, the prior art discloses the use of a combined apparatus for inspecting an object, in which both electrons and ions can be directed onto the object to be inspected. 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 is used to generate ions for preparing the object (for example ablating material from the object or applying material to the object) or for imaging. For this purpose, a deflection device in the form of a scanning device is used to scan the ions over the object. The SEM is used in particular for observing the preparation and also for further inspecting the prepared or unprepared object.

[0008] When generating an image of an object, a particle beam apparatus can be used to image the object with high spatial resolution. In particular, this is achieved by using a primary electron beam with a very small diameter in the plane of the object. In addition, the higher the electrons of the primary electron beam are initially accelerated in the particle beam apparatus and are finally decelerated to a desired energy (referred to as the landing energy) in the objective lens or in the region between the objective lens and the object, the better the spatial resolution can be. For example, an acceleration voltage of 2 kV to 30 kV is used to accelerate the electrons of the primary electron beam and to guide them through the electron beam column of the particle beam apparatus. The electrons of the primary electron beam are decelerated to the desired landing energy only in the region between the objective lens and the object, and these electrons impinge on the object with this desired landing energy. For example, the landing energy of the electrons in the primary electron beam is in the range between 10 e V and 30 keV.

[0009] The image created by a particle beam apparatus can be affected by disturbances in the particle beam apparatus. For example, it is known that the primary electron beam and / or the ion beam are disturbed by external disturbances (for example in the form of acoustic or electromagnetic oscillations). For example, the external disturbance can be described as a disturbance function. The disturbance function describes the disturbance in the path of the particle beam in the particle beam apparatus compared to the path of the particle beam in the particle beam apparatus in the absence of disturbances. As already presented above, the above-mentioned disturbances are, for example, acoustic oscillations or electromagnetic oscillations that are not caused by the particle beam apparatus itself but by external influences. In particular, sound, movement of a building, and / or electronic devices can generate disturbances.

[0010] For example, the disturbance function can be described as an oscillation as follows:

[0011] v x\(\xi(t;\alpha,\omega,\Phi,\omega_0)=\alpha\cdot\sin(\omega\cdot t+\omega_0)\cdot\cos\Phi\) [1]

[0012] v y \(\eta(t;\alpha,\omega,\Phi,\omega_0)=\alpha\cdot\sin(\omega\cdot t+\omega_0)\cdot\sin\Phi\) [2]

[0013] wherein,

[0014] x is the first direction along the scanning area and in the plane of the scanning area,

[0015] y is the second direction along the scanning area and in the plane of the scanning area, wherein the first direction and the second direction are perpendicular to each other,

[0016] α is the amplitude of oscillation,

[0017] ω corresponds to 2*π*f, where f is the frequency of oscillation,

[0018] ω0 corresponds to the phase shift generated by the time of recording the image of the scanning area of the object,

[0019] corresponds to the polar angle of the final reproduction interference direction, and

[0020] t is the time for detecting interacting particles and / or interacting radiation.

[0021] The degree to which the primary electron beam and / or ion beam is affected by one or more of the above interferences is such that the primary electron beam and / or ion beam cannot be guided to the desired scan point in the scanning area of the object, but is guided to another undesired scan point. Ultimately, one or more interferences mean that instead of generating an image of the desired scan point in the desired scanning area, an image of the scan point (i.e., the actual scan point) to which the primary electron beam and / or ion beam is actually guided due to one or more interferences is generated.

[0022] For example, the desired scan point in the desired scanning area on the object can be described as the grid point of the ideal measurement grid. If N desired scan points are assumed, the ideal measurement grid includes, for example, the following desired scan points, where each scan point is defined by three variables x, y, and t:

[0023] (x1, y1, t1), (x2, y2, t2),......, (x N-1 , y N-1 , t N-1 ), (x N , y N , t N ),

[0024] wherein, N is an integer and corresponds to the total number of desired scan points, xi is the desired scan point SP i is the first coordinate in a first direction (e.g., the x-direction) along the surface of the object, and yi is the desired scan point SP i is the second coordinate in a second direction (e.g., the y-direction) along the surface of the object, wherein the first direction is aligned perpendicular to the second direction, and wherein, t i is the time at which the particle beam is directed to the desired scan point SP i and / or the time at which interaction particles and / or interaction radiation are detected at the desired scan point SP i and wherein the following applies: 1 ≤ i ≤ N, where i is an integer. If a row and column notation is used to represent the ideal measurement grid, the ideal measurement grid can be represented as follows:

[0025] (x 1，1 , y 1，1 , t 1，1 ), ……, (x m,n , y m，n , t m，n )

[0026] where m is the total number of rows in the ideal measurement grid, where n is the total number of columns in the ideal measurement grid, and where the following applies to the total number N of desired scan points: N = m * n.

[0027] Assuming that all grid parameters of the ideal measurement grid are known except for the start time of detecting interaction particles and / or interaction radiation, the coordinates of the desired scan points of the ideal measurement grid can also be represented as follows:

[0028] x i,j = (j - 1)·Δx [3]

[0029] y i,j = (i - 1)·Δy [4]

[0030] t i,j = t 1,1 + ((i - 1)·n + j - 1)·Δt mess + (i - 1)·Δ sprung [5]

[0031] where Δx is the first distance between a first desired scan point and a second desired scan point in the first direction (e.g., the horizontal direction), where Δy is the second distance between a first desired scan point and a third desired scan point in the second direction (e.g., the vertical direction), where Δt mess is the measurement time (i.e., the detection time) at each desired scan point, and where Δt sprungis the retrace time from a first position of a first scan point on a scan line to a second position of a second scan point on the scan line.

[0032] As described above, one or more interferences ultimately result in an image of scan points in a scan region where the primary electron beam and / or ion beam is actually directed due to one or more interferences, rather than an image of the desired scan points in the desired scan region. The scan points actually struck by the primary electron beam and / or ion beam can be described as nodes of a disturbed measurement grid. Considering the interference function, the disturbed measurement grid is generated as follows:

[0033]

[0034] where and are the coordinates of a scan point (i.e., the actual scan point) in the disturbed measurement grid.

[0035] Regarding the prior art, reference is made to DE 11 2009 002 402 T5, US 9 129 353 B2, US 2016 / 0163501 A1, US 10 614 999 B2, US 2019 / 0103250 A1 and EP 3 503 157 A1.

[0036] Therefore, it is necessary to correct the current interference of the particle beam used in the object image recorded by the particle beam device in order to obtain an image of the actually desired scan points. Summary of the Invention

[0037] Therefore, an object of the present invention is to specify a method, a computer program product and a particle beam device for carrying out the method, by means of which the object image recorded by the particle beam device is corrected with respect to the current interference of the particle beam used, so that an image of the actually desired scan points is obtained.

[0038] According to the present invention, this object is achieved by a method having the features of claim 1. The features of claim 12 specify a computer program product having program code for controlling a particle beam device for carrying out the method. The particle beam device according to the present invention is given by the features of claim 13. Further features of the present invention become apparent from the following description, the appended claims and / or the drawings.

[0039] The method according to the present invention is used to generate a corrected image of an object using a particle beam device. The particle beam device includes at least one beam generator for generating a particle beam having charged particles. For example, the charged particles are electrons or ions.

[0040] The method according to the invention comprises controlling a guiding device of a particle beam device with a control device of the particle beam device. The guiding device is designed to guide a particle beam of the particle beam device to a desired scanning point in a scanning area on an object. For example, the guiding device takes the form of an objective lens for focusing the particle beam onto the object. In addition or alternatively, the guiding device includes scanning means for scanning the particle beam over the object. However, the invention is not limited to the above embodiments of the guiding device. Rather, any guiding device suitable for the invention may be used.

[0041] In a further step of the method according to the invention, the guiding device is used to guide the particle beam over the scanning area of the object. Subsequently, interaction particles and / or interaction radiation are detected by at least one detector of the particle beam device. The interaction particles and / or interaction radiation are generated by the interaction of the particle beam with the object. The detector is used to generate a detection signal based on the interaction particles detected by the detector and / or the interaction radiation detected by the detector. Now, the control device is used to generate a plurality of images of the scanning area of the object based on the detection signal.

[0042] In a further step, the control device is used to define an interference function having at least one interference parameter. The interference parameter has a predetermined value. The interference function describes the interference in the path of the particle beam in the particle beam device as compared to the path of the particle beam in the particle beam device in the absence of interference. The above interference is, for example, an acoustic oscillation or an electromagnetic oscillation that is not caused by the particle beam device itself but is generated, for example, by external influences. In particular, sound, movement of a building, and / or electronic devices may generate interference.

[0043] As already mentioned above, the interference function can be described, for example, as an oscillation, as follows:

[0044] v x (t; α, ω, Φ, ω0) = α · sin(ω · t + ω0) · cos Φ [1]

[0045] v y (t; α, ω, Φ, ω0) = α · sin(ω · t + ω0) · sin Φ [2]

[0046] Regarding the variables (i.e., the interference parameters), reference is made to the further explanations made above, which also apply here.

[0047] Furthermore, the method according to the invention comprises using the control device to calculate an actual scanning point in the scanning area by means of the interference function. The actual scanning point is the scanning point to which the particle beam is actually guided by the guiding device due to the interference of the particle beam, rather than the desired scanning point.

[0048] Accordingly, the above-mentioned plurality of images generated for the scanned area are based on the detection of the actual detection signals at the actual scan points. Therefore, the plurality of images generated in this way are also referred to as actual images hereinafter. The actual scan points ultimately lie on the disturbed (actual) measurement grid. Considering equations [6] and [7], the coordinates of the actual scan points of the actual plurality of images can be described as follows:

[0049]

[0050] where i is an integer and the following applies: 1 ≤ i ≤ N, where N is the total number of actual scan points; where k is an integer and the following applies: 1 ≤ k ≤ NBILD, where NBILD is the total number of the actual plurality of images. The variables α, ω, Φ, ω0 1 ......ω0 NBild are unknown variables (i.e., unknown interference parameters). Referring to the further explanations made above, these explanations also apply here.

[0051] Furthermore, a control device is used to calculate the expected detection signal at the expected scan points by means of the actual scan points and the (actual) detection signals, and for the plurality of images, an expected image of the scanned area of the object is generated based on the expected detection signals. In this regard, in this step of the method according to the invention, the image that would be obtained if the particle beam were not disturbed (i.e., the actually expected image) is calculated. Embodiments for calculating the expected detection signal at the expected scan points and generating the expected image are further explained below.

[0052] Furthermore, the method according to the invention includes using a control device to compare the generated expected images with each other. In other words, at least one of the generated expected images is compared with at least one other of the generated expected images. During the comparison, for each of the expected scan points, a corresponding subtraction signal is generated by subtracting the expected detection signal of one image in the expected image at the corresponding expected scan point from the expected detection signal of the other image in the expected image at the corresponding expected scan point. Therefore, a plurality of subtraction signals are obtained depending on the plurality of expected scan points. What has been set forth above can also be described as follows:

[0053] Generally, during the measurement of the actual detection signals at the actual scan points in the disturbed measurement grid, the intensity value of each actual scan point is obtained. For example, the intensity values of the actual N scan points are obtained

[0054]

[0055] where the value range of the above-mentioned intensity values is, for example, from 0 to 1, and the above-mentioned interval extreme values are included in this interval. For example, a single generated expected image can be calculated by a function ψ as follows:

[0056]

[0057] where f i is the intensity value of the desired detection signal at the i-th desired scan point. As described above, a plurality of actual images are generated, and for each of the plurality of actual images, a corresponding desired image is generated. To represent this, an ideal measurement grid can be defined as follows to simplify the notation:

[0058] X = (x1...x N ; y1…y N )

[11]

[0059] To simplify the notation, a perturbed measurement grid is defined as follows:

[0060]

[0061] Then, the k-th generated desired image can be calculated, for example, by the function ψ as follows:

[0062]

[0063] where the following applies:

[0064]

[0065] and where is the intensity value of the generated (actual) image. Now, a quality metric that depends on the selected interference parameter and thus changes accordingly with the interference parameter can be determined (calculated). For example, the quality metric can be formed based on the difference. Hereinafter, the quality metric is particularly denoted by the letter "E" and can be determined, for example, as follows:

[0068]

[0069] where the term within the double vertical bars is the difference between the generated desired image and the average of the generated desired images. The average of the generated desired images is produced as follows:

[0070]

[0071] The double vertical bars in equation

[14] denote the norm. Thus, this is the norm of the difference. Ultimately, the quality metric is a function that maps the selected nuisance parameter to a numerical value. In other words, when calculating the quality metric, the numerical value is determined based on the selected nuisance parameter. This numerical value is a quality metric for the accuracy of the selected nuisance parameter and thus the quality of the resulting corrected image. For example, the norm is the taxicab norm (also known as the 1-norm). However, the present invention is not limited to this norm. Instead, any norm suitable for the present invention can be used in the present invention, particularly the Euclidean norm (also known as the 2-norm).

[0072] In the method according to the present invention, a control device is now used to perform at least one of the following tests: (i) perform a test on whether the quality metric is less than or equal to a predetermined threshold, and (ii) perform a test on whether the quality metric does not deviate or only slightly deviates from a pre-determined quality metric. For example, there is a slight deviation when the deviation is less than 5%, less than 4%, less than 3%, less than 2%, less than 1%, less than 0.5%, or less than 0.1%. For example, the pre-determined quality metric is pre-determined or has been pre-determined when performing the method according to the present invention. The above item (i) and / or item (ii) are hereinafter also referred to as the (multiple) conditions regarding the quality metric. If (1) the quality metric is less than or equal to a predetermined threshold, and / or if (2) the quality metric does not deviate or only slightly deviates from a pre-determined quality metric (i.e., if the (multiple) conditions regarding the quality metric are satisfied), then one of the following steps is performed:

[0073] (a) Use the control device to define the corrected image by selecting one of the generated desired images as the corrected image;

[0074] (b) Use the interference function to calculate the corrected image, which includes a region of the object that is different from and / or at least partially covers the scanned region. In other words, use the interference function to calculate the corrected image of any desired region on the object. In an embodiment of the method according to the present invention, the complete scanned region of the object is used as the above region;

[0075] (c) Using an interference function with interference parameters to control a guiding device with a control device so as to guide a particle beam to a desired scanning point in a scanning area on an object, and using the guiding device to guide the particle beam to the desired scanning point on the scanning area of the object. Further, a detector of the particle beam device is used to detect additional interaction particles and / or additional interaction radiation, where the additional interaction particles and / or additional interaction radiation are generated by an additional interaction of the particle beam with the object. The detector is used to generate an additional detection signal based on the additional interaction particles detected by the detector and / or the additional interaction radiation detected by the detector. Further, the control device is used to generate a corrected image of the scanning area of the object based on the additional detection signal. Finally, in this embodiment of the method according to the invention, the interference function is kept available at the guiding device so that despite the influence of the interference, the particle beam is still guided to the desired scanning point. In other words, the guiding device is designed such that the influence of the interference is taken into account when guiding the particle beam so that despite the influence of the interference, the particle beam is still guided to the desired scanning point. Finally, the inverse interference is kept available in the guiding device so as to cancel the interference on the particle beam.

[0076] As further explained in more detail below, the method according to the invention allows to identify the interference parameters of the interference function such that the generated desired images of a plurality of recorded images are as similar to each other as possible, where the recorded images form an image series. For example, the Nelder-Mead-Simplex method and / or the "simulated annealing" method known to the applicant can be used to determine suitable interference parameters.

[0077] The method according to the invention ensures that the object image recorded by the particle beam device is corrected for the current interference of the used particle beam such that an image of the desired scanning point is obtained. Thus, a desired image is generated. In particular, what the method according to the invention provides is to determine the interference function and to quantify one or more interference parameters of the interference function. Due to the interference function obtained in this way, a corrected image of the scanning area on the object can be obtained.

[0078] Additionally or alternatively, according to one embodiment of the method of the present invention, the method comprises the steps of: if (i) the quality metric is greater than a predetermined threshold and / or if (ii) the quality metric does not deviate only slightly from a pre-determined quality metric (i.e., if the (one or more) conditions regarding the quality metric are not met), then change the value of the interference parameter and re-perform the steps mentioned below and above: re-calculate the actual scan points; re-calculate the actual detection signals; re-generate the desired image; re-compare the generated desired images; re-generate one or more subtraction signals; re-calculate the quality metric based on the modified interference parameter; and re-perform at least one of the following steps: (i) perform a test on whether the re-calculated quality metric is less than or equal to the predetermined threshold depending on the modified interference parameter (and the subtraction signal), and (ii) perform a test on whether the re-calculated quality metric does not deviate or only slightly deviates from the pre-determined quality metric. If (1) the re-calculated quality metric is less than or equal to the predetermined threshold, and / or if (2) the re-calculated quality metric does not deviate or only slightly deviates from the pre-determined quality metric, then perform one of the following steps (a), (b), or (c). Finally, this embodiment of the method according to the present invention includes an optimization step. The value of the interference parameter should be selected and optimized such that (i) it is below the predetermined threshold and / or (ii) the quality metric does not change or hardly changes. Finally, this embodiment relates to (i) approximating the quality metric to the predetermined threshold by adjusting the value of the interference parameter such that the quality metric is below the predetermined threshold or corresponds to the predetermined threshold, and / or (ii) approximating the quality metric to a fixed value. In this case, the desired images generated based on multiple actual images are very similar to each other. The above embodiment of the method according to the present invention is not limited to a single change in the value of the interference parameter and a single repetition of the above steps. Instead, for example, it is provided that the value of the interference parameter is modified multiple times, and the above steps are repeated after each change in the value of the interference parameter.

[0079] As will be explained in further detail below, the interference function may also include a plurality of interference parameters. In this case, the above optimization step comprises determining the minimum value of the quality metric for all possible configurations of the plurality of interference parameters.

[0080] Additionally or alternatively, according to another embodiment of the method of the present invention, defining the interference function comprises at least one of the following steps: (i) loading the interference function from a database of the particle beam device into a control device of the particle beam device; (ii) inputting the interference function into the control device of the particle beam device; (iii) using the control device to predetermine the interference function; and (iv) using the control device to generate the interference function. For example, the optimization steps mentioned above are provided when generating the interference function. If the interference function comprises a plurality of interference parameters, the above optimization steps may comprise obtaining the minimum value of the quality metric for all possible configurations of the plurality of interference parameters.

[0081] Additionally or alternatively, according to yet another embodiment of the method of the present invention, defining the interference function comprises: (i) defining the interference function as an oscillation; and (ii) defining the interference parameters as the amplitude, frequency, direction, phase or time of the interference. In yet another embodiment of the method according to the present invention, the interference function has at least two interference parameters. For example, the interference function has at least two of the following interference parameters: the amplitude, frequency, direction, phase or time of the interference. Interference and thus the interference function taking the form of an oscillation have been further explained above. Referring to the explanations given above, these explanations also apply here.

[0082] Additionally or alternatively, according to an embodiment of the method of the present invention, the interference parameter is a first interference parameter, and wherein defining the interference function further comprises defining the interference function using at least one second interference parameter. The second interference parameter has a predetermined value. For example, the amplitude, frequency, direction, phase or time of the interference is used as the second interference parameter. In particular, it is provided that the second interference parameter is different from the first interference parameter.

[0083] Additionally or alternatively, according to another embodiment of the method according to the invention, for a plurality of interference parameters, the method according to the invention is carried out sequentially, where only a single interference parameter is considered in each individual sequence. In its alternative, it is provided that the method according to the invention is carried out while considering a plurality of interference parameters simultaneously. In other words, this embodiment of the method according to the invention provides that, for example, the first interference parameter and, for example, the second interference parameter are modified simultaneously, and / or the steps explained below and further explained above are carried out: recalculating the actual scan points; recalculating the expected detection signal; regenerating the expected image; re-comparing the generated expected image; regenerating one or more subtraction signals; recalculating and testing the quality metric (as explained above); and, for example, carrying out one of steps (a), (b), or (c). In the alternative, it is provided that the value of the first interference parameter is first modified and / or only the first interference parameter is used to carry out the following steps and the steps further mentioned above: recalculating the actual scan points; recalculating the expected detection signal; regenerating the expected image; re-comparing the generated expected image; regenerating one or more subtraction signals; recalculating and testing the quality metric (as explained above); and, for example, carrying out one of steps (a), (b), or (c). Subsequently, the value of the second interference parameter is modified and / or the above steps are carried out again only using the second interference parameter. In yet another embodiment of the method according to the invention, alternatively, it is provided that the value of the second interference parameter is modified and the above steps are carried out only using the second interference parameter, and subsequently the value of the first interference parameter is modified and the above steps are carried out again only using the first interference parameter.

[0084] If the particle beam is affected by a plurality of interferences that can each be described by an interference function, then, taking into account the interference functions, the perturbed measurement grid is produced as follows by modifying equations [6] and [7]:

[0085]

[0086]

[0087] where and are the coordinates of the i-th scan point (i.e., the actual scan point) among the N scan points in the perturbed measurement grid. This results in a total number of variables (i.e., interference parameters) to be optimized that has increased multiplicatively according to the total number of external interferences.

[0088] As already mentioned above, one or more interference parameters of the interference function can be optimized in the optimization step. In embodiments of the method according to the invention in which multiple interferences act on the particle beam, this optimization step can likewise be carried out. For example, multiple interferences can be described by corresponding interference functions, which has been further described above. In an alternative, it is provided that multiple interferences are described in a single interference function, where the total number of variables to be optimized (i.e., the interference parameters) increases multiplicatively. For example, the optimization of the interference parameters among multiple interference parameters can be carried out simultaneously for all interference parameters to be considered in the sole interference function of the current interference or all interference functions. In an alternative, for example, it is provided that the interference parameters of the sole interference function of the current interference or all interference functions are optimized successively in each case. For example, for this purpose, an order of the interference parameters to be optimized is predetermined. Then, the interference parameters of the interference function or all interference functions are optimized successively according to the predetermined order. This is also referred to as the sequential method. In this case, for example, the optimization for each interference parameter is carried out as follows: the value of the interference parameter is modified, and then the following steps and the steps further mentioned above are carried out using the modified value of the interference parameter: recalculating the actual scan points; recalculating the expected detection signal; regenerating the expected image; re-comparing the generated expected image; regenerating one or more subtraction signals; recalculating and testing the quality metric (as explained above); and, for example, carrying out one of steps (a), (b), or (c). For example, the interference parameters that have already been optimized remain fixed during the optimization of the interference parameters that have not yet been optimized. In other words, the optimized interference parameters are no longer modified. In an alternative, it is provided that when optimizing the interference parameters that have not yet been optimized, the interference parameters that have already been optimized are also optimized again. For example, the predetermined order can be based on the expected degree of influence on the corrected image and / or on the frequency of the corresponding generated interference.

[0089] If the number of interferences affecting the particle beam cannot be accurately known, then additionally or alternatively provided in one embodiment of the method according to the invention is that the optimization is carried out according to an iterative method. In other words, first, one or more interference parameters of the first interference function of the first interference are optimized as has been further described above. Subsequently, it is tested whether the particle beam is affected by further interferences to be considered. In an alternative, if the user determines that the image correction is insufficient, the user himself can add an interference function to the method according to the invention. If further interferences are considered, one or more interference parameters of the further interference function of the further interference are considered and optimized. For example, an interference function can be added until a corrected image with sufficient image quality for the user can be obtained. In the above embodiment, for example, the optimized interference parameters remain fixed during the optimization of the non-optimized interference parameters. In other words, the optimized interference parameters are not modified any further. In an alternative, it is provided that when the non-optimized interference parameters are optimized, the already optimized interference parameters are also optimized again.

[0090] It has been taken into account that the optimization of at least one of the above interference parameters is particularly well implemented if the change in the interference parameter takes into account at least one of the following boundary conditions: (i) the amplitude is non-negative; (ii) the frequency is non-negative; (iii) the phase shift is arbitrary, but multiples of the period are not considered; and (iv) the range of the polar angle is between 0° and 180°. It has also been taken into account that the maximum value of the amplitude can be limited (for example, ten times the distance between two adjacent scan points). It has been taken into account that the amplitude of the actual interference cannot be greater than this maximum value. Regarding the phase shift and the polar angle, no further limitations are required. Consideration has shown that the quality metric can be easily affected by changing the amplitude, the phase shift, and the polar angle, and the quality metric can be reduced relative to a threshold.

[0091] It has also been taken into account that the change in frequency has a significant impact on image correction and thus greatly affects the optimization. To achieve reliable correction of the image, it has been found that for the optimization, the frequency range should be limited to a few hertz around the actual interference frequency. It has also been taken into account that to compensate for the large changes caused by the change in frequency, the measurement time (i.e., the detection time) at each desired scan point and the flyback time Δt from the first position of the first scan point on the scan line to the second position of the second scan point on the scan line sprung should be considered as parameters in the optimization steps that have been further explained above and will be further explained below.

[0092] Additionally or alternatively, according to another embodiment of the method according to the invention, the scanned area is subdivided into a plurality of areas, and the method according to the invention is performed for each of the plurality of areas of the scanned area with respect to the optimization of one or more interference parameters. Then, the corrected image of the entire scanned area is created using the thus obtained optimized values of the corresponding interference parameters. For example, the average value of the optimized values of one or more interference parameters over the plurality of areas of the scanned area is determined, or the optimized values of one or more interference parameters are interpolated according to the detection time.

[0093] Additionally or alternatively, according to yet another embodiment of the method according to the invention, only a subset of the desired scan points is used, in particular, to optimize one or more interference parameters. In this context, the subset forms, for example, a partial area of the scanned area. In an alternative, the subset is distributed, for example, regularly or irregularly over the entire scanned area of the object. In this context, it is advantageous that the interference of the particle beam occurs in the area of the subset of the desired scan points in order to obtain a meaningful optimization. For example, the subset of the desired scan points is selected such that intensity variations occur due to the object structures present in the subset. In particular, these structures are edges or corners.

[0094] Additionally or alternatively, according to yet another embodiment of the method according to the invention, the quality measure already mentioned above is further specified in order to obtain a good corrected image. For this purpose, the quality measure is enhanced by additional regularization that evaluates the distortion remaining in the corrected image. It has been taken into account that then the quality measure E should be determined as follows reg :

[0095]

[0096] where

[0097]

[0098] where R is a regularization term, and where represents the intensity gradient in one of the above directions, for example in the second direction (in particular in the y - direction). This regularization preferably smooths the edge profile rather than distorts the edge at the object edge. Further, the influence of this regularization can be set by the coefficient λ of the regularization term R (where the following applies: λ≥0).

[0099] Additionally or alternatively, according to another embodiment of the method of the present invention, the calculation of the desired detection signal at the desired scan point is implemented by interpolation. The desired scan point, the actual scan point, and the actual detection signal are used during interpolation. Any suitable interpolation method can be used during interpolation, such as linear interpolation, non-linear interpolation, triangular interpolation, logarithmic interpolation, nearest neighbor interpolation, and / or spline interpolation. The present invention is not limited to the above interpolation methods. Instead, any interpolation method suitable for the present invention can be used. For example, the above function ψ is an interpolation operator.

[0100] Additionally or alternatively, according to another embodiment of the method of the present invention, the calculation of the desired detection signal at the desired scan point is implemented by inpainting, wherein the desired scan point, the actual scan point, and the actual detection signal are used and considered during inpainting. Inpainting is a known method by which an image can be processed in a way that reconstructs the missing parts of the image.

[0101] Additionally or alternatively, according to an embodiment of the method of the present invention, predetermined guiding parameters are used when controlling a guiding device. When the first value of the guiding parameter is used, the particle beam is guided in a first manner. In contrast, when the second value of the guiding parameter is used, the particle beam is guided in a second manner. For example, the guiding parameter is (i) the residence time of the particle beam at a predetermined position of the object or (ii) the retrace time of the particle beam from a first position on a scan line to a second position on the scan line, where the particle beam is guided along the scan line. The guiding parameter is not limited to the above embodiments. Instead, any parameter suitable for the present invention can be used as the guiding parameter. Further, according to this embodiment of the method of the present invention, the first value and / or the second value of the guiding parameter and the first value and / or the second value of the particle beam parameter are used when guiding the particle beam over the scan region of the object.

[0102] Additionally or alternatively, according to another embodiment of the method of the present invention, when controlling the guiding device, a predetermined first guiding parameter and a predetermined second guiding parameter are used. The first guiding parameter is different from the second guiding parameter. For example, the first guiding parameter is (i) the first dwell time of the particle beam at a predetermined position of the object or (ii) the first retrace time of the particle beam from a first position on the scan line to a second position on the scan line, wherein the particle beam is guided along the scan line. The first guiding parameter is not limited to the above embodiments. Instead, any parameter suitable for the present invention can be used as the first guiding parameter. Further, for example, the second guiding parameter is (i) the second dwell time of the particle beam at a predetermined position of the object or (ii) the second retrace time of the particle beam from a first position on the scan line to a second position on the scan line, wherein the particle beam is guided along the scan line. The second guiding parameter is not limited to the above embodiments. Instead, any parameter suitable for the present invention can be used as the second guiding parameter. Further, this embodiment provides that when controlling the control device, a predetermined first particle beam parameter and a predetermined second particle beam parameter are used. The first particle beam parameter and the second particle beam parameter are different from each other. When the first particle beam parameter is used, the particle beam has a first beam characteristic. In contrast, when the second particle beam parameter is used, the particle beam has a second beam characteristic. For example, the following items at a predetermined position of the particle beam on the object are used as the first particle beam parameter: the first current intensity of the particle beam, the first energy of the particles in the particle beam, or the first range of the particle beam. The first particle beam parameter is not limited to the above embodiments. Instead, any parameter suitable for the present invention can be used as the first particle beam parameter. Further, for example, the following items at a predetermined position of the particle beam on the object are used as the second particle beam parameter: the second current intensity of the particle beam, the second energy of the particles in the particle beam, or the second range of the particle beam. The second particle beam parameter is not limited to the above embodiments. Instead, any parameter suitable for the present invention can be used as the second particle beam parameter. Additionally, according to this embodiment of the method of the present invention, when guiding the particle beam over the scan region of the object, the first guiding parameter and the first particle beam parameter are first used, and then the second guiding parameter and the second particle beam parameter are used, in order to generate a plurality of images. In an alternative, it is provided that when guiding the particle beam over the scan region of the object, the first guiding parameter and the second particle beam parameter are first used, and then the second guiding parameter and the first particle beam parameter are used, in order to generate a plurality of images.

[0103] Additionally or alternatively, according to a further embodiment of the method according to the invention, there is provided that generating a plurality of (actual) images comprises using a control device to generate a first series of a plurality of images of a scanning area and a second series of a plurality of images of the scanning area. In this context, in particular, it is provided that the above-mentioned first guiding parameters and the above-mentioned first particle beam parameters are used when generating the first series of a plurality of images of the scanning area. Further, in particular, it is provided that the above-mentioned second guiding parameters and the above-mentioned second particle beam parameters are used when generating the second series of a plurality of images of the scanning area. In an alternative, for example, it is provided that the above-mentioned first guiding parameters and the above-mentioned second particle beam parameters are used when generating the first series of a plurality of images of the scanning area. Further, in particular, it is provided that the above-mentioned second guiding parameters and the above-mentioned first particle beam parameters are used when generating the second series of a plurality of images of the scanning area.

[0104] For example, according to a further embodiment of the method according to the invention, when performing step (c), a perturbation function with perturbation parameters is used in such a way when the control device controls the guiding device that: the perturbation parameters have the same value when the particle beam is guided to a first scanning point among the desired scanning points and when the particle beam is guided to a second scanning point among the desired scanning points. For example, a phase with the same value is used as the perturbation parameter. This embodiment of the method according to the invention is based on the following consideration: Whenever the perturbation occurring in each case has the same perturbation parameter (e.g., the same phase value), the particle beam is always guided to the first scanning point among the desired scanning points and the second scanning point among the desired scanning points. Eventually, the particle beam is synchronized with the perturbation in time. Therefore, the particle beam is finally perturbed in the same way at each scanning point of the desired scanning points and is deflected accordingly in the same way. Since the recorded image of the scanning area is finally uniformly shifted and the perturbation is known, a corrected image of the scanning area can be generated when the known perturbation is taken into account.

[0105] It is explicitly mentioned that the order of the individual steps of the embodiments of the method according to the invention further explained above and further explained below is not limited to the order described in the embodiments of the method according to the invention further explained above and further explained below. Instead, any order suitable for the individual steps of the invention can be used for the method according to the invention. In addition, at least two of these steps further specified above or further specified below can also be performed in parallel with each other.

[0106] The invention also relates to a computer program product comprising program code that can be loaded or is loaded into a processor of a particle beam device, wherein, when the program code is executed in the processor, the program code controls the particle beam device such that 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 is performed.

[0107] The present invention further relates to a particle beam device for processing, imaging, and / or analyzing an object, wherein the particle beam device has been further explained above and will be further described in detail below. A brief overview of this will be given below.

[0108] The particle beam device according to the present invention includes at least one beam generator for generating a particle beam having charged particles. The charged particles are, for example, electrons or ions. In addition, the particle beam device according to the present invention includes at least one guiding device for guiding the particle beam over a scanning area of the object. The guiding device takes, for example, the form of an objective lens for focusing the particle beam onto the object. In addition or alternatively, the guiding device includes a scanning device for scanning the particle beam over the object or takes the form of a scanning device. Note the fact that the guiding device is not limited to the above embodiments. Rather, any device suitable for the present invention can be used as the guiding device. For example, the guiding device can take the form of a magnetic deflection unit and / or an electrostatic deflection unit. Further, the particle beam device according to the present invention includes at least one detector for detecting interaction particles and / or interaction radiation, which are emitted from the interaction between the particle beam and the object when the particle beam impinges on the object. In addition, the particle beam device according to the present invention includes at least one display device for displaying an image of the object and / or data analysis regarding the object, wherein the image and / or analysis is generated based on detection signals generated from the detected interaction particles and / or the detected interaction radiation. In addition, the particle beam device according to the present invention includes at least one control device having at least one processor in which a computer program product having the features further mentioned above is loaded.

[0109] Additionally or alternatively, according to another embodiment of the particle beam device of the present invention, it is provided that the beam generator takes the form of a first beam generator, and the particle beam takes the form of a first particle beam having first charged particles. The guiding device takes the form of a first guiding device for guiding the first particle beam onto an object. Further, the particle beam device according to the present invention includes at least one second beam generator for generating a second particle beam including second charged particles. In addition, the particle beam device according to the present invention includes at least one second guiding device for guiding the second particle beam onto the object. The second guiding device takes the form of, for example, an additional objective lens for focusing the second particle beam onto the object. In addition or as an alternative, the second guiding device includes an additional scanning device for scanning the second particle beam onto the object or takes the form of an additional scanning device. Note the fact that the second guiding device is not limited to the above embodiments. Instead, any device suitable for the present invention can be used as the second guiding device. For example, the second guiding device can take the form of a magnetic deflection unit and / or an electrostatic deflection unit.

[0110] In particular, it is provided that the particle beam device according to the present invention takes the form of an electron beam device and / or an ion beam device. BRIEF DESCRIPTION OF THE DRAWINGS

[0111] Additional practical embodiments and advantages of the present invention are described below in conjunction with the drawings, in which:

[0112] Figure 1 A schematic diagram of a particle beam device according to the present invention is shown;

[0113] Figure 1A Is shown in connection with Figure 1 A schematic diagram of a control device connected to the functional units and guiding devices of the particle beam device of

[0114] Figure 2 A schematic diagram of another particle beam device according to the present invention is shown;

[0115] Figure 2A Is shown in connection with Figure 2 A schematic diagram of a control device connected to the functional units and guiding devices of the particle beam device of

[0116] Figure 3 A schematic diagram of yet another particle beam device according to the present invention is shown;

[0117] Figure 3A Is shown in connection with Figure 3 A schematic diagram of a control device connected to the functional units and guiding devices of the particle beam device of

[0118] Figure 4 A flowchart of a first embodiment of a method according to the present invention is shown;

[0119] Figure 5 shows a flow chart of a second embodiment of the method according to the present invention;

[0120] Figure 6 shows a flow chart of a third embodiment of the method according to the present invention; and

[0121] Figure 7 shows a flow chart of a third embodiment of the method according to the present invention. Detailed Description of the Invention

[0122] The present invention will now be explained in detail with the aid of a particle beam apparatus in the form of a SEM and in the form of a combined apparatus having an electron beam column and an ion beam column. It is expressly mentioned that the present invention can be used in any particle beam apparatus, in particular in any electron beam apparatus and / or any ion beam apparatus.

[0123] Figure 1 Shows a schematic view of a SEM 100. The SEM 100 includes a first beam generator in the form of an electron source 101, which takes the form of a cathode. Further, the SEM 100 is provided with an extraction electrode 102 and an anode 103, which is placed at one end of the beam guiding tube 104 of the SEM 100. For example, the electron source 101 takes the form of a thermal field emitter. However, the present invention is not limited to such an electron source 101. Rather, any electron source suitable for the present invention can be used.

[0124] The electrons emitted from the electron source 101 form a primary electron beam. The electrons are accelerated to the anode potential due to the potential difference between the electron source 101 and the anode 103. In the embodiment presented here, the anode potential is 100 V to 35 kV, for example 5 kV to 15 kV, in particular 8 kV, relative to the ground potential of the housing of the sample chamber 120. However, alternatively, the anode potential can also be at the ground potential.

[0125] Two condenser lenses are arranged on the beam guiding tube 104, specifically a first condenser lens 105 and a second condenser lens 106. When looking in the direction of the first objective lens 107 starting from the electron source 101, in this case, the first condenser lens 105 is arranged in front, followed by the second condenser lens 106. It is expressly mentioned that further embodiments of the SEM 100 can include only a single condenser lens. A first aperture unit 108 is arranged between the anode 103 and the first condenser lens 105. Together with the anode 103 and the beam guiding tube 104, the first aperture unit 108 is at a high voltage potential (specifically the potential of the anode 103), or connected to the ground. The first aperture unit 108 includes a plurality of first apertures 108A, in Figure 1One of them is depicted. For example, there are two first apertures 108A. Each of the many first apertures 108A has a different aperture diameter. With the aid of an adjustment mechanism (not shown), a desired first aperture 108A can be set on the optical axis OA of the SEM 100. The fact is explicitly mentioned that in a further embodiment, the first aperture unit 108 can be provided with only a single first aperture 108A. In this embodiment, the adjustment mechanism can be dispensed with. Then, the first aperture unit 108 is fixed. A fixed second aperture unit 109 is arranged between the first condenser lens 105 and the second condenser lens 106. As an alternative, it is provided that the second aperture unit 109 is movable.

[0126] The first objective lens 107 includes pole pieces 110 in which drill holes are formed. The beam guiding tube 104 is guided through the drill holes. Coils 111 are arranged in the pole pieces 110.

[0127] An electrostatic deceleration device is arranged in the lower region of the beam guiding tube 104. The electrostatic deceleration device includes a single electrode 112 and a tubular electrode 113. The tubular electrode 113 is arranged at one end of the beam guiding tube 104, which end faces the object 125 arranged on the movable object holder 114.

[0128] The tubular electrode 113 is at the potential of the anode 103 together with the beam guiding tube 104, while the single electrode 112 and the object 125 are at a lower potential with respect to the potential of the anode 103. In the present case, this is the ground potential of the housing of the sample chamber 120. In this way, the electrons of the primary electron beam can be decelerated to the desired energy for inspecting the object 125.

[0129] The SEM 100 further includes a scanning device 115 by means of which the primary electron beam can be deflected and scanned (or raster scanned) over the object 125. In this process, the electrons of the primary electron beam interact with the object 125. The interaction generates interaction particles which are detected. In particular, the interaction particles are electrons (so-called secondary electrons) emitted from the surface of the object 125 or backscattered electrons (so-called backscattered electrons) of the primary electron beam.

[0130] The object 125 and the single electrode 112 can also be at different potentials and at a potential different from ground. This enables the site of deceleration of the primary electron beam with respect to the object 125 to be set. For example, if deceleration is performed very close to the object 125, the aberration becomes smaller.

[0131] A detector arrangement including a first detector 116 and a second detector 117 is arranged in the in-beam guiding tube 104 for detecting secondary electrons and / or backscattered electrons. In this case, in the in-beam guiding tube 104, the first detector 116 is arranged on the source side along the optical axis OA, and the second detector 117 is arranged on the object side along the optical axis OA. The first detector 116 and the second detector 117 are arranged offset from each other in the direction of the optical axis OA of the SEM 100. Both the first detector 116 and the second detector 117 have respective passage openings through which the primary electron beam can pass. The first detector 116 and the second detector 117 are at approximately the potential of the anode 103 and the in-beam guiding tube 104. The optical axis OA of the SEM 100 extends through the respective passage openings.

[0132] The second detector 117 is mainly used for detecting secondary electrons. When exiting from the object 125, the secondary electrons initially have low kinetic energy and random movement directions. The secondary electrons are accelerated in the direction of the first objective lens 107 by a strong extraction field emitted from the tubular electrode 113. The secondary electrons enter the first objective lens 107 substantially parallel. The beam diameter of the secondary electron beam remains small even in the first objective lens 107. Then, the first objective lens 107 has a strong effect on the secondary electrons and generates a relatively short secondary electron focus at a sufficiently steep angle with respect to the optical axis OA, so that the secondary electrons diverge significantly from each other downstream of the focus and impinge on the effective area of the second detector 117. In contrast, the second detector 117 only detects a small portion of the electrons backscattered at the object 125 (i.e., backscattered electrons having a relatively high kinetic energy compared to the secondary electrons when exiting from the object 125). The high kinetic energy of the backscattered electrons when exiting from the object 125 and the angle with respect to the optical axis OA have the effect that the beam waist (i.e., the beam region with the smallest diameter) of the backscattered electrons is located near the second detector 117. Most of the backscattered electrons pass through the passage opening of the second detector 117. Therefore, the first detector 116 is basically used for detecting backscattered electrons.

[0133] In another embodiment of the SEM 100, the first detector 116 can additionally be formed with a backscattering grating 116A. The backscattering grating 116A is arranged on the side of the first detector 116 facing the object 125. The backscattering grating 116A has a negative potential with respect to the potential of the in-beam guiding tube 104, so that only the high-energy backscattered electrons pass through the backscattering grating 116A to reach the first detector 116. In addition or alternatively, the second detector 117 includes an additional backscattering grating which has a similar embodiment and a similar function as the above-mentioned backscattering grating 116A of the first detector 116.

[0134] Further, in the sample chamber 120, the SEM 100 includes a chamber detector 119, such as an Everhart-Thornley detector or an ion detector, which has a detection surface coated with metal and blocking light.

[0135] 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.

[0136] Explicitly mention the fact that the apertures of the first aperture unit 108 and the second aperture unit 109, as well as the through openings in the first detector 116 and the through openings in the second detector 117, are depicted in an exaggerated manner. The ranges of the through openings in the first detector 116 and the second detector 117 perpendicular to the optical axis OA are in the range of 0.5 mm to 5 mm. For example, the through openings take the form of circles and have diameters perpendicular to the optical axis OA in the range of 1 mm to 3 mm.

[0137] The second aperture unit 109 is configured as a pinhole aperture in the embodiment shown here and is provided with a second aperture 118 for the passage of the primary electron beam, and the range of this second aperture is in the range of 5 μm to 500 μm, for example, 35 μm. In an alternative, another embodiment provides that the second aperture unit 109 is provided with a plurality of apertures, and these apertures can be mechanically displaced relative to the primary electron beam or the primary electron beam can be made to reach these apertures by using electrical and / or magnetic deflection elements. The second aperture unit 109 is designed as a pressure-stage aperture. This separates the first region, in which the electron source 101 is arranged and there is an ultra-high vacuum (10 -7 hPa to 10 -12 hPa), from the second region, which has a high vacuum (10 - 3 hPa to 10 -7 hPa). The second region is the intermediate pressure region of the beam guiding tube 104, which leads to the sample chamber 120.

[0138] The sample chamber 120 is under vacuum. To generate the vacuum, a pump (not shown) is arranged on the sample chamber 120. In Figure 1 the depicted embodiment, the sample chamber 120 operates within a first pressure range or within a second pressure range. The first pressure range only includes pressures less than or equal to 10 -3 hPa, and the second pressure range only includes pressures greater than 10 -3 hPa. The sample chamber 120 is vacuum-sealed to ensure these pressure ranges.

[0139] The object holder 114 is arranged at the sample stage 122. The sample stage 122 is movable in three mutually perpendicular directions, specifically the x-direction (first stage axis), the y-direction (second stage axis), and the z-direction (third stage axis). In addition, the sample stage 122 can be rotated about two mutually perpendicular rotation axes (stage rotation axes). The present invention is not limited to the sample stage 122 described above. Rather, the sample stage 122 can have additional translation axes and rotation axes along or about which the sample stage 122 can be moved.

[0140] The SEM 100 further includes a third detector 121 arranged in the sample chamber 120. More precisely, when viewed along the optical axis OA from the electron source 101, the third detector 121 is arranged downstream of the sample stage 122. The sample stage 122 and thus the object holder 114 can be rotated in such a way that the primary electron beam can radiate through the object 125 arranged at the object holder 114. When the primary electron beam passes through the object 125 to be inspected, the electrons of the primary electron beam interact with the material of the object 125 to be inspected. The third detector 121 detects the electrons passing through the object 125 to be inspected.

[0141] A radiation detector 500 for detecting interaction radiation (e.g., x-ray radiation and / or cathodoluminescence) is arranged on the sample chamber 120. 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. This is not shown for the sake of clarity. The control device 123 processes the 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 the detection signals in the form of an image on the monitor 124.

[0142] The control device 123 further includes a database 126 in which data is stored and from which data is read out. In addition, the control device 123 is connected to the scanning device 115. In addition, the control device 123 is connected to other units of the SEM 100. This will be shown in more detail below.

[0143] The control device 123 of the SEM 100 includes a processor. A computer program product including program code is loaded into the processor, and the program code, when executed, performs a method for operating the SEM 100. This will be explained in more detail below.

[0144] Figure 1AShows a schematic view of the control device 123 of the SEM 100. As already partially further mentioned above, the control device 123 of the SEM 100 is wired to the functional units and the guiding device of the SEM 100. The functional units should be understood as structural units of the SEM 100 that can be set in any way. For example, the position of the functional units in the SEM 100 can be set. In addition or as an alternative, it is provided that the electrostatic and / or magnetic embodiments of the functional units are set. The present invention is not limited to the above setting options. Instead, the functional units can be set in any way suitable for the present invention. The guiding device should be understood to mean any unit for guiding the primary electron beam onto the object 125 and also a unit for shaping the primary electron beam subsequently guided onto the object 125. For example, the guiding device takes the following forms: a first objective lens 107 for focusing the primary electron beam onto the object 125, an electrostatic and / or magnetic unit for beam shaping or for beam guiding, an astigmatism corrector, a bunching lens, or a mechanically adjustable aperture unit, and the primary electron beam is defined by means of the guiding device. Figure 1A Shows the control device 123, which is wired to the functional units and / or the guiding device of the SEM 100. Specifically, the control device 123 is connected to the electron source 101, extraction electrode 102, anode 103, first aperture unit 108, first bunching lens 105, second bunching lens 106, first detector 116, second detector 117, third detector 121, chamber detector 119, radiation detector 500, scanning device 115, coil 111, tubular electrode 113, single electrode 112, and sample stage 122.

[0145] Figure 2 Shows a particle beam device in the form of a combined device 200. The combined device 200 includes two particle beam columns. First, as already depicted in Figure 1 it is shown that the combined device 200 is provided with an SEM 100, but without a sample chamber 120. Instead, the SEM 100 is arranged in the sample chamber 201. The sample chamber 201 is under vacuum. To generate the vacuum, a pump (not shown) is arranged on the sample chamber 201. In Figure 2 the depicted embodiment, the sample chamber 201 operates in a first pressure range or in a second pressure range. The first pressure range only includes pressures less than or equal to 10 -3 hPa, and the second pressure range only includes pressures greater than 10 -3 hPa. The sample chamber 201 is vacuum-sealed to ensure these pressure ranges.

[0146] Disposed in the sample chamber 201 is a chamber detector 119, which takes the form of, for example, an Everhart-Thornley detector or an ion detector, and which has a detection surface coated with metal and blocking light. Further, a third detector 121 is disposed in the sample chamber 201.

[0147] The SEM 100 is used to generate a first particle beam, specifically a primary electron beam that has been further described above, and has an optical axis that has been mentioned above, which optical axis is provided with the reference numeral 709 in Figure 2 and is hereinafter also referred to as the first beam axis. Secondly, the combined device 200 is provided with an ion beam device 300, which is likewise disposed on the sample chamber 201. The ion beam device 300 likewise has an optical axis that is provided with the reference numeral 710 in Figure 2 and is hereinafter also referred to as the second beam axis.

[0148] The SEM 100 is disposed vertically with respect to the sample chamber 201. In contrast, the ion beam device 300 is disposed at an angle that is inclined by approximately 0° to 90° with respect to the SEM 100. For example, Figure 2 an arrangement of approximately 50° is shown in. The ion beam device 300 includes a second beam generator in the form of an ion beam generator 301. The ion beam generator 301 generates ions that form a second particle beam in the form of an ion beam. These ions are accelerated by means of an extraction electrode 302 at a predeterminable electric potential. The second particle beam then passes through the ion optical unit of the ion beam device 300, which ion optical unit includes a bunching lens 303 and a second objective lens 304. The second objective lens 304 finally generates an ion probe that is focused onto an object 125 disposed on an object holder 114. The object holder 114 is disposed at the sample stage 122.

[0149] Above the second objective lens 304 (i.e., in the direction of the ion beam generator 301) are disposed an adjustable or selectable aperture 306, a first electrode arrangement 307, and a second electrode arrangement 308, where the first electrode arrangement 307 and the second electrode arrangement 308 take the form of scanning electrodes. The second particle beam is scanned (or raster scanned) over the surface of the object 125 by means of the first electrode arrangement 307 and the second electrode arrangement 308, where the first electrode arrangement 307 acts in a first direction and the second electrode arrangement 308 acts in a second direction, which second direction is opposite to the first direction. For example, this implements scanning in the x direction. Scanning in the y direction, which is perpendicular thereto, is caused by additional electrodes (not shown) that are rotated by 90° at the first electrode arrangement 307 and the second electrode arrangement 308.

[0150] As explained above, the object holder 114 is disposed at the sample stage 122. InFigure 2 In the illustrated embodiment, the sample stage 122 can also be moved in three mutually perpendicular directions, specifically the x-direction (first stage axis), the y-direction (second stage axis), and the z-direction (third stage axis). In addition, the sample stage 122 can be rotated about two mutually perpendicular rotation axes (stage rotation axes).

[0151] For a better illustration of the individual units of the combined device 200, the distances between the individual units of the combined device 200 depicted in Figure 2 are depicted in an exaggerated manner.

[0152] On the sample chamber 201, a radiation detector 500 for detecting interaction radiation (e.g., x-ray radiation and / or cathodoluminescence) is arranged. The radiation detector 500 is connected to a control device 123, which includes a monitor 124.

[0153] The control device 123 processes the detection signals generated by the first detector 116 ( Figure 2 not shown in Figure 2 ), the second detector 117 (

[0154] not shown in Figure 2 ), the chamber detector 119, the third detector 121, and / or the radiation detector 500, and displays the detection signals in the form of an image on the monitor 124.

[0155] The control device 123 of the combined device 200 includes a processor. A computer program product including program code is loaded into the processor, and the program code, when executed, performs a method for operating the combined device 200. This will be explained in further detail below.

[0156] Figure 2AA schematic view of the control device 123 of the combined device 200 is shown. As has been further partly mentioned above, the control device 123 of the combined device 200 is wired to the functional units and the guiding device of the combined device 200. The functional units should be understood as structural units of the combined device 200 that can be set in any way. For example, the position of the functional units in the combined device 200 can be set. In addition or as an alternative, it is provided that the electrostatic and / or magnetic embodiments of the functional units are set. The present invention is not limited to the above setting options. Instead, the functional units can be set in any way suitable for the present invention. The guiding device should be understood to refer to any unit for guiding a primary electron beam and / or an ion beam onto the object 125, and also to a unit for shaping the primary electron beam and / or ion beam subsequently guided onto the object 125. For example, the guiding device takes the following forms: the first objective lens 107 or the second objective lens 304, electrostatic and / or magnetic units for beam shaping or for beam guiding, an astigmatism corrector, a bunching lens, or a mechanically adjustable aperture unit, and the primary electron beam and / or ion beam is defined by means of the guiding device. Figure 2A The control device 123 is shown, which is wired to the electron source 101, the extraction electrode 102, the anode 103, the first aperture unit 108, the first bunching lens 105, the second bunching lens 106, the first detector 116, the second detector 117, the third detector 121, the chamber detector 119, the radiation detector 500, the scanning device 115, the coil 111, the tubular electrode 113, the single electrode 112, the sample stage 122, the extraction electrode 302 in the ion beam generator 301, the bunching lens 303 in the ion beam device 300, the adjustable or selectable aperture 306, the first electrode arrangement 307, and the second electrode arrangement 308.

[0157] Figure 3 It is a schematic view of another embodiment of a particle beam device according to the present invention. This embodiment of the particle beam device is provided with the reference numeral 400 and includes a mirror corrector for correcting, for example, chromatic aberration and / or spherical aberration. The particle beam device 400 includes a particle beam column 401, which takes the form of an electron beam column and basically corresponds to the electron beam column of a corrected SEM. However, the particle beam device 400 is not limited to an SEM having a mirror corrector. Instead, the particle beam device 400 can include any type of corrector unit.

[0158] The particle beam column 401 includes a particle beam generator in the form of an electron source 402 (cathode), an extraction electrode 403, and an anode 404. For example, the electron source 402 takes the form of a thermionic field emitter. The electrons emitted from the electron source 402 are accelerated to reach the anode 404 due to the potential difference between the electron source 402 and the anode 404. Accordingly, a particle beam in the form of an electron beam is formed along the first optical axis OA1.

[0159] After the particle beam exits from the electron source 402, the particle beam is guided along a beam path corresponding to the first optical axis OA1. The first electrostatic lens 405, the second electrostatic lens 406, and the third electrostatic lens 407 are used to guide the particle beam.

[0160] Furthermore, a beam guiding device is used to set the particle beam along the beam path. The beam guiding device in this embodiment includes a source setting unit having two magnetic deflection units 408 arranged along the first optical axis OA1. In addition, the particle beam device 400 includes an electrostatic beam deflection unit. A first electrostatic beam deflection unit 409 (also in the form of a quadrupole in another embodiment) is arranged between the second electrostatic lens 406 and the third electrostatic lens 407. The first electrostatic beam deflection unit 409 is arranged downstream of the magnetic deflection unit 408. A first multipole unit 409A in the form of a first magnetic deflection unit is arranged on one side of the first electrostatic beam deflection unit 409. In addition, a second multipole unit 409B in the form of a second magnetic deflection unit is arranged on the other side of the first electrostatic beam deflection unit 409. The first electrostatic beam deflection unit 409, the first multipole unit 409A, and the second multipole unit 409B are set for the purpose of setting the particle beam relative to the axis of the third electrostatic lens 407 and the entrance window of the beam deflection device 410. The first electrostatic beam deflection unit 409, the first multipole unit 409A, and the second multipole unit 409B can interact like a Wien filter. Another magnetic deflection element 432 is arranged at the entrance of the beam deflection device 410.

[0161] The beam deflection device 410 serves as a particle beam deflector that deflects the particle beam in a specific manner. The beam deflection device 410 includes a plurality of magnetic sectors, specifically a first magnetic sector 411A, a second magnetic sector 411B, a third magnetic sector 411C, a fourth magnetic sector 411D, a fifth magnetic sector 411E, a sixth magnetic sector 411F, and a seventh magnetic sector 411G. The particle beam enters the beam deflection device 410 along the first optical axis OA1 and is deflected by the beam deflection device 410 in the direction of the second optical axis OA2. The beam is deflected by an angle of 30° to 120° by means of the first magnetic sector 411A, by means of the second magnetic sector 411B, and by means of the third magnetic sector 411C. The second optical axis OA2 is oriented at the same angle relative to the first optical axis OA1. The beam deflection device 410 also deflects the particle beam guided along the second optical axis OA2 precisely in the direction of the third optical axis OA3. The beam deflection is provided by the third magnetic sector 411C, the fourth magnetic sector 411D, and the fifth magnetic sector 411E. In Figure 3In the embodiments, the deflections relative to the second optical axis OA2 and relative to the third optical axis OA3 are provided by deflecting the particle beam by an angle of 90°. Accordingly, the third optical axis OA3 extends coaxially with the first optical axis OA1. However, it is noted that the particle beam apparatus 400 according to the invention described herein is not limited to a deflection angle of 90°. Instead, the beam deflection device 410 may select any suitable deflection angle, such as 70° or 110°, such that the first optical axis OA1 does not extend coaxially with the third optical axis OA3. For more details regarding the beam deflection device 410, reference is made to WO 2002 / 067286A2.

[0162] After the particle beam has been deflected by the first magnetic sector 411A, the second magnetic sector 411B, and the third magnetic sector 411C, the particle beam is guided along the second optical axis OA2. The particle beam is guided to the electrostatic mirror 414 and travels along the fourth electrostatic lens 415, the third multipole unit 416A in the form of a magnetic deflection unit, the second electrostatic beam deflection unit 416, the third electrostatic beam deflection unit 417, and the fourth multipole unit 416B in the form of a magnetic deflection unit on its path to the electrostatic mirror 414. The electrostatic mirror 414 includes a first mirror electrode 413A, a second mirror electrode 413B, and a third mirror electrode 413C. The electrons of the particle beam reflected back at the electrostatic mirror 414 travel again along the second optical axis OA2 and re-enter the beam deflection device 410. Then, these electrons are deflected to the third optical axis OA3 by the third magnetic sector 411C, the fourth magnetic sector 411D, and the fifth magnetic sector 411E.

[0163] The electrons of the particle beam exit the beam deflection device 410 and are guided along the third optical axis OA3 to the object 425 intended to be inspected and arranged in the object holder 114. On the path to the object 425, the particle beam is guided to the fifth electrostatic lens 418, the beam guiding tube 420, the fifth multipole unit 418A, the sixth multipole unit 418B, and the objective lens 421. The fifth electrostatic lens 418 is an electrostatic immersion lens. By the fifth electrostatic lens 418, the particle beam is decelerated or accelerated to the potential of the beam guiding tube 420.

[0164] By means of the objective lens 421, the particle beam is focused onto the focal plane in which the object 425 is arranged. The object holder 114 is arranged at the movable sample stage 424. The movable sample stage 424 is arranged in the sample chamber 426 of the particle beam apparatus 400. The sample stage 424 is movable in three mutually perpendicular directions, specifically the x direction (first stage axis), the y direction (second stage axis), and the z direction (third stage axis). In addition, the sample stage 424 can be rotated about two mutually perpendicular rotation axes (stage rotation axes).

[0165] The sample chamber 426 is under vacuum. To generate the vacuum, a pump (not shown) is arranged on the sample chamber 426. In Figure 3 the depicted embodiment, the sample chamber 426 operates within a first pressure range or within a second pressure range. The first pressure range only includes pressures less than or equal to 10 -3 hPa, and the second pressure range only includes pressures greater than 10 -3 hPa. The sample chamber 426 is vacuum-sealed to ensure these pressure ranges.

[0166] The objective lens 421 can take the form of a combination of a magnetic lens 422 and a sixth electrostatic lens 423. The end of the beam guiding tube 420 can also be an electrode of an electrostatic lens. After exiting the beam guiding tube 420, the particles of the particle beam device are decelerated to the potential of the object 425. The objective lens 421 is not limited to the combination of the magnetic lens 422 and the sixth electrostatic lens 423. Instead, the objective lens 421 can take any suitable form. For example, the objective lens 421 can also take the form of a pure magnetic lens or a pure electrostatic lens.

[0167] The particle beam focused on the object 425 interacts with the object 425. Interaction particles are generated. In particular, secondary electrons are emitted from the object 425, or backscattered electrons are backscattered at the object 425. The secondary electrons or backscattered electrons are also accelerated and guided into the beam guiding tube 420 along the third optical axis OA3. In particular, the trajectories of the secondary electrons and backscattered electrons on the path of the particle beam travel in a direction opposite to the particle beam.

[0168] The particle beam device 400 includes a first analysis detector 419, which is arranged along the beam path between the beam deflection device 410 and the objective lens 421. The secondary electrons traveling in a direction oriented at a large angle with respect to the third optical axis OA3 are detected by the first analysis detector 419. The backscattered electrons and secondary electrons (i.e., the backscattered electrons and secondary electrons that are at a short axial distance from the third optical axis OA3 at the site of the first analysis detector 419) at a small axial distance from the third optical axis OA3 at the site of the first analysis detector 419 enter the beam deflection device 410 and are deflected by the fifth magnetic sector 411E, the sixth magnetic sector 411F, and the seventh magnetic sector 411G along the detection beam path 427 to the second analysis detector 428. For example, the deflection angle is 90° or 110°.

[0169] The first analysis detector 419 generates a detection signal mainly generated by the emitted secondary electrons. The detection signal generated by the first analysis detector 419 is transmitted to the control device 123 and is used to obtain information about the characteristics of the interaction region between the focused particle beam and the object 425. In particular, the focused particle beam is scanned over the object 425 using the scanning device 429. With the detection signal generated by the first analysis detector 419, an image of the scanned region of the object 425 can then be generated and displayed on the display unit. For example, the display unit is the monitor 124 arranged at the control device 123.

[0170] The second analysis detector 428 is also connected to the control device 123. The detection signal from the second analysis detector 428 is transmitted to the control device 123 and is used to generate an image of the scanned region of the object 425 and display the image on the display unit. For example, the display unit is the monitor 124 arranged at the control device 123.

[0171] On the sample chamber 426, a radiation detector 500 for detecting interaction radiation (e.g., x-ray radiation and / or cathodoluminescence) is arranged. The radiation detector 500 is connected to the control device 123, which includes the monitor 124. The control device 123 processes the detection signals from the radiation detector 500 and displays these detection signals in the form of an image on the monitor 124.

[0172] The control device 123 further includes a database 126, where data is stored and read out from the database. In addition, the control device 123 is connected to the scanning device 429.

[0173] The control device 123 of the particle beam device 400 includes a processor. A computer program product including program code is loaded into the processor, and the program code, when executed, performs a method for operating the particle beam device 400.

[0174] Figure 3AShows a schematic diagram of the control device 123 of the particle beam device 400. As already partly further mentioned above, the control device 123 of the particle beam device 400 is wired to the functional units and the guiding device of the particle beam device 400. The functional units are to be understood as structural units of the particle beam device 400 that can be set in any way. For example, the position of the functional units in the particle beam device 400 can be set. In addition or as an alternative, it is provided that the electrostatic and / or magnetic embodiments of the functional units are set. The present invention is not limited to the above setting options. Rather, the functional units can be set in any way suitable for the present invention. The guiding device is to be understood as referring to any unit for guiding the particle beam onto the object 425 and also to a unit for shaping the particle beam subsequently guided onto the object 425. For example, the guiding device takes the following form: a first objective lens 421 for focusing the particle beam onto the object 425, an electrostatic and / or magnetic unit for beam shaping or for beam guiding, an astigmatism corrector, a bunching lens, or a mechanically adjustable aperture unit, and the particle beam is defined by means of the guiding device. Figure 3A Shows the control device 123, which is wired to the electron source 402, extraction electrode 403, anode 404, first electrostatic lens 405, second electrostatic lens 406, third electrostatic lens 407, magnetic deflection unit 408, first electrostatic beam deflection unit 409, first multipole unit 409A, second multipole unit 409B, beam deflection device 410, first magnetic sector 411A, second magnetic sector 411B, third magnetic sector 411C, fourth magnetic sector 411D, fifth magnetic sector 411E, sixth magnetic sector 411F, seventh magnetic sector 411G, first mirror electrode 413A, second mirror electrode 413B, third mirror electrode 413C, fourth electrostatic lens 415, second electrostatic beam deflection unit 416, third multipole unit 416A, fourth multipole unit 416B, third electrostatic beam deflection unit 417, fifth electrostatic lens 418, fifth multipole unit 418A, sixth multipole unit 418B, first analysis detector 419, magnetic lens 422, sixth electrostatic lens 423, sample stage 424, second analysis detector 428, scanning device 429, additional magnetic deflection element 432, and radiation detector 500.

[0175] In the following, the SEM 100 according to Figure 1 is used to explain the method according to the present invention. The explanations given below also apply analogously to the implementation of the method according to the present invention using the combined device 200 according to Figure 2 or the particle beam device 400 according to Figure 3

[0176] Figure 4 Shows an embodiment of the method according to the present invention, which is performed by the Figure 1performed by the SEM 100.

[0177] The method according to the invention is used to generate a corrected image of an object 125 using the SEM 100. In step S1 of an embodiment of the method according to the invention, the guiding device of the SEM 100 is controlled by the control device 123 of the SEM 100. The guiding device is designed to guide the primary electron beam of the SEM to a desired scanning point in the scanning area on the object 125. For example, the guiding device takes the following form: extraction electrode 102, anode 103, first aperture unit 108, first bunching lens 105, second bunching lens 106, scanning device 115, coil 111, tubular electrode 113, single electrode 112, and / or sample stage 122. However, the invention is not limited to the above embodiments of the guiding device. Instead, any guiding device suitable for the present invention can be used.

[0178] In another step S2 of an embodiment of the method according to the invention, the primary electron beam is guided over the scanning area of the object 125 using at least one of the guiding devices 102, 103, 105, 106, 108, 111, 112, 113, 115, and / or 122. Then, in step S3, the interaction particles and / or interaction radiation are detected using the detector of the SEM 100. For example, the first detector 116, the second detector 117, the chamber detector 119, and / or the third detector 121 are used as detectors for detecting the interaction particles. The radiation detector 500 is used to detect the interaction radiation. The interaction particles and / or interaction radiation are generated by the interaction of the primary electron beam with the object 125. For example, the interaction particles are secondary electrons and backscattered electrons. For example, the interaction radiation is x-ray radiation and / or cathodoluminescence.

[0179] In step S3 of an embodiment of the method according to the invention, at least one of the above detectors 116, 117, 119, 121, and 500 is used to generate a detection signal based on the detected interaction particles and / or the detected interaction radiation. In step S4 of an embodiment of the method according to the invention, the control device 123 now generates a plurality of images of the scanning area of the object 125 based on the generated detection signal.

[0180] In another step S5, the control device 123 is used to define an interference function having at least one interference parameter. The interference parameter has a predefined value. The interference function describes the interference in the path of the primary electron beam in the SEM 100 as compared to the path of the primary electron beam in the SEM 100 in the absence of interference. For example, defining the interference function includes at least one of the following steps: (i) loading the interference function from the database 126 of the SEM 100 into the control device 123 of the SEM 100; (ii) inputting the interference function into the control device 123 of the SEM 100; (iii) using the control device 123 of the SEM 100 to predetermine the interference function; and (iv) using the control device 123 of the SEM 100 to generate the interference function.

[0181] In a further embodiment of the method according to the invention, defining the interference function in step S5 includes: (i) defining the interference function as an oscillation; and (ii) defining the interference parameter as the amplitude, frequency, direction, phase or time of the interference. The above-mentioned interference is, for example, an acoustic oscillation or an electromagnetic oscillation that is not caused by the SEM 100 itself but is generated, for example, by external influences. In particular, sound, movement of a building and / or electronic devices may generate interference.

[0182] As already mentioned above, the interference function can be described, for example, as an oscillation, as follows:

[0183] v x (t; α, ω, Φ, ω0) = α·sin(ω·t + ω0)·cosΦ [1]

[0184] v y (t; α, ω, Φ, ω0) = α·sin(ω·t + ω0)·sinΦ [2]

[0185] Regarding the variables (i.e., the interference parameters), reference is made to the further explanations made above, which also apply here.

[0186] Furthermore, step S6 includes using the control device 123 to calculate the actual scan points in the scan area by means of the interference function. The actual scan points are the scan points to which the primary electron beam is actually guided by at least one of the above-mentioned guiding devices 102, 103, 105, 106, 108, 111, 112, 113, 115 and / or 122 due to the interference with the primary electron beam, rather than the desired scan points.

[0187] In step S4 of this embodiment of the method according to the invention, the plurality of images of the scan area of the object 125 are generated correspondingly based on the detection of the actual detection signals at the actual scan points. The plurality of images generated in this way can also be referred to as actual images. The actual scan points ultimately lie on a disturbed (actual) measurement grid. For example, the actual scan points form the nodes of the disturbed (actual) measurement grid. As explained above, by considering equations [6] and [7], the actual scan points of the actual plurality of images can be described as follows:

[0188]

[0189] where i is an integer and the following applies: 1 ≤ i ≤ N, where N is the total number of actual scan points; where k is an integer and the following applies: 1 ≤ k ≤ NBILD, where NBILD is the total number of the actual plurality of images. The variables α, ω, Φ, ω0 1 ……ω0 NBild are unknown variables (i.e., unknown disturbance parameters).

[0190] Furthermore, step S7 of this embodiment of the method according to the invention includes using the control device 123 to calculate the desired detection signals at the desired scan points by means of the actual scan points and the (actual) detection signals. For the plurality of images generated in step S4, then in step S8, the desired images of the scan area of the object 125 are generated based on the desired detection signals. In this regard, in step S8, the image that would be obtained if the primary electron beam were not disturbed is calculated (i.e., the actually desired image).

[0191] Furthermore, step S9 of the embodiment of the method according to the invention includes using the control device 123 to compare the generated desired images with each other. In other words, at least one of the generated desired images is compared with at least one other of the generated desired images. During the comparison, for each of the desired scan points, a corresponding subtraction signal is generated by subtracting the desired detection signal of one of the desired images at the corresponding desired scan point from the desired detection signal of the other of the desired images at the corresponding desired scan point. Thus, a plurality of subtraction signals are obtained depending on the plurality of desired scan points. Regarding the possible mathematical representation of the above statements, reference is made to the further explanations made above, which also apply here.

[0192] In an embodiment of the method according to the invention, now, in step S10, the control device 123 is used to determine (calculate) a quality metric that depends on the selected interference parameter and accordingly changes based on the interference parameter. For example, the quality metric can be formed by a difference. For example, the quality metric is determined by means of equation

[14] . Referring to the further explanations made above, these explanations also apply here. In the method according to the invention, the control device 123 is now used to perform at least one of the following tests: (i) perform a test on whether the quality metric is less than or equal to a predetermined threshold, and (ii) perform a test on whether the quality metric does not deviate or only slightly deviates from a predetermined quality metric. For example, there is a slight deviation when the deviation is less than 5%, less than 4%, less than 3%, less than 2%, less than 1%, less than 0.5% or less than 0.1%. For example, the predetermined quality metric is predetermined or has been predetermined when performing the method according to the invention. If (1) the quality metric is less than or equal to a predetermined threshold, and / or if (2) the quality metric does not deviate or only slightly deviates from a predetermined quality metric (i.e., if the (multiple) conditions regarding the quality metric are met), then one of the following steps is performed:

[0193] (a) Use the control device 123 to define a corrected image by selecting one of the generated desired images as the corrected image;

[0194] (b) Use the interference function to calculate a corrected image that includes a region of the object 125 that is different from and / or at least partially covers the scanned region. In other words, use the interference function to calculate the corrected image of any desired region on the object 125. In an embodiment of the method according to the invention, the corrected image of the complete scanned region of the object 125 is used;

[0195] (c) Use an interference function with interference parameters to control at least one of the guiding devices 123, 102, 103, 105, 106, 108, 111, 112, 113, 115, and / or 122 with a control device 123 so as to guide a primary electron beam to a desired scan point in a scan area on an object 125, and use the guiding device to guide the primary electron beam to the desired scan point on the scan area of the object 125. Additionally, detect additional interaction particles using at least one of the detectors 116, 117, 119, and 121 and / or detect additional interaction radiation using a detector 500 of the SEM 100, where the additional interaction particles and / or additional interaction radiation are generated by additional interactions of the primary electron beam with the object 125. Generate an additional detection signal based on the additional interaction particles detected by at least one of the detectors 116, 117, 119, and 121 and / or the additional interaction radiation detected by the detector 500. Further, use the control device 123 to generate a corrected image of the scan area of the object 125 based on the additional detection signal. Finally, in this embodiment of the method according to the invention, keep the interference function available at at least one of the guiding devices 123, 102, 103, 105, 106, 108, 111, 112, 113, 115, and / or 122 such that despite the influence of interference, the primary electron beam is still guided to the desired scan point. In other words, at least one of the guiding devices 123, 102, 103, 105, 106, 108, 111, 112, 113, 115, and / or 122 is designed such that the influence of interference is taken into account when guiding the primary electron beam, such that despite the influence of interference, the primary electron beam is still guided to the desired scan point. Finally, keep the reverse interference available at at least one of the guiding devices 123, 102, 103, 105, 106, 108, 111, 112, 113, 115, and / or 122 such that the interference on the primary electron beam is cancelled out.

[0196] If it is determined in step S10 that the (multiple) conditions regarding the quality metric are not met, steps S5 to S10 are performed again. Now, in step S5, the value of the interference parameter of the above interference function is changed. Furthermore, step S6 includes using the control device 123 to recalculate the actual scan points in the scan area by means of the interference function. The actual scan points are the scan points to which the primary electron beam is actually guided by at least one of the above guiding devices 102, 103, 105, 106, 108, 111, 112, 113, 115, and / or 122 due to the interference with the primary electron beam, rather than the desired scan points. In addition, step S7 of this embodiment of the method according to the invention includes using the control device 123 to recalculate the desired detection signal at the desired scan points by means of the actual scan points and the (actual) detection signals. For the multiple images generated in step S4, then in step S8, a desired image of the scan area of the object 125 is generated based on the desired detection signal. In this regard, in step S8, the image that would be obtained if the primary electron beam were not interfered with (i.e., the actually desired image) is calculated. In addition, step S9 of the embodiment of the method according to the invention includes using the control device 123 to re-compare the generated desired images with each other. In other words, at least one image among the desired images generated in the repeated step S8 is compared with at least one other image among the images generated in the repeated step S8. During the comparison, for each scan point among the desired scan points, a corresponding subtraction signal is generated by subtracting the desired detection signal of one image in the desired image at the corresponding desired scan point from the desired detection signal of the other image in the desired image at the corresponding desired scan point. Thus, a plurality of subtraction signals are obtained depending on the plurality of desired scan points. Regarding the possible mathematical representation of the above statements, reference is made to the further explanations made above, which also apply here. In the method according to the invention, now, in step S10, the control device 123 is used to recalculate the quality metric based on the modified interference parameter, and at least one of the following steps is repeated: (i) performing a test on whether the recalculated quality metric depending on the modified interference parameter (and the subtraction signal) is less than or equal to a predetermined threshold, and (ii) performing a test on whether the recalculated quality metric does not deviate or only slightly deviates from a predetermined quality metric. If (1) the recalculated quality metric is less than or equal to a predetermined threshold, and / or if (2) the recalculated quality metric does not deviate or only slightly deviates from a predetermined quality metric (i.e., if the (multiple) conditions regarding the quality metric are met), then in step S11 of this embodiment of the method according to the invention, one of the following steps is performed:

[0197] (a) Using the control device 123 to define a corrected image by selecting one of the desired images generated in the repeated step S8 as the corrected image;

[0198] (b) Use an interference function to calculate a corrected image that includes a region of the object 125 that is different from and / or at least partially covers the scanned region. In other words, use an interference function to calculate a corrected image of any desired region on the object 125. In an embodiment of the method according to the invention, the corrected image includes the complete scanned region of the object 125;

[0199] (c) Use an interference function with interference parameters to control, with the control device 123, at least one of the above-described guiding devices 102, 103, 105, 106, 108, 111, 112, 113, 115, and / or 122 so as to direct a primary electron beam to a desired scan point in the scanned region on the object 125, and use at least one of the above-described guiding devices 102, 103, 105, 106, 108, 111, 112, 113, 115, and / or 122 to direct the primary electron beam to the desired scan point in the scanned region of the object 125. Additionally, detect additional interaction particles using at least one of the detectors 116, 117, 119, and 121 and / or detect additional interaction radiation using the detector 500 of the SEM 100, wherein the additional interaction particles and / or the additional interaction radiation are generated by additional interactions of the primary electron beam with the object 125. Generate an additional detection signal based on the additional interaction particles detected by at least one of the above-described detectors 116, 117, 119, and 121 and / or the additional interaction radiation detected by the above-described detector 500. Further, use the control device 123 to generate a corrected image of the scanned region of the object 125 based on the additional detection signal. Finally, in this embodiment of the method according to the invention, keep the interference function available at at least one of the above-described guiding devices 102, 103, 105, 106, 108, 111, 112, 113, 115, and / or 122 such that, despite the influence of the interference, the primary electron beam is still directed to the desired scan point. In other words, at least one of the above-described guiding devices 102, 103, 105, 106, 108, 111, 112, 113, 115, and / or 122 is designed such that the influence of the interference is taken into account when guiding the primary electron beam, such that, despite the influence of the interference, the primary electron beam is still directed to the desired scan point. Finally, keep the reverse interference available at at least one of the above-described guiding devices 102, 103, 105, 106, 108, 111, 112, 113, 115, and / or 122 such that the interference on the primary electron beam is cancelled.

[0200] Finally, running steps S5 to S10 again includes an optimization step. The value of the interference parameter should be selected and optimized such that (i) the quality metric is below a predetermined threshold and / or (ii) the quality metric does not change or hardly changes. Finally, this embodiment relates to (1) approximating the quality metric to a predetermined threshold by adjusting the value of the interference parameter such that the quality metric is below or corresponds to the predetermined threshold, and / or (2) approximating the quality metric to a fixed value. In this case, the desired images generated based on the plurality of actual images are very similar to each other. The above embodiments of the method according to the invention are not limited to a single change in the value of the interference parameter and a single repetition of the above steps. On the contrary, for example, it is provided that the value of the interference parameter is modified multiple times (i.e., steps S5 to S10 are run multiple times).

[0201] As will be explained in further detail below, the interference function may also include a plurality of interference parameters. In this case, the above optimization step includes obtaining the minimum value of the quality metric for all possible configurations of the plurality of interference parameters.

[0202] According to an embodiment of the method according to the invention, in step S5, the interference parameter is taken as the first interference parameter. In step S5, defining the interference function further includes defining the interference function with at least one second interference parameter. The second interference parameter has a predetermined value. For example, the amplitude, frequency, direction, phase or time of the interference is used as the second interference parameter. In particular, it is provided that the second interference parameter is different from the first interference parameter.

[0203] If the interference function includes a first interference parameter and a second interference parameter, according to an embodiment of the method according to the invention, steps S5 to S10 are performed sequentially for the first interference parameter and the second interference parameter. In other words, first, the value of the first interference parameter is selected in step S5, and then steps S6 to S10 are implemented using only the first interference parameter. If it is determined in step S10 that the (multiple) conditions regarding the quality metric are not satisfied, steps S5 to S10 are run again. However, when doing so, only the value of the second interference parameter is set or modified in step S5. Then, steps S6 to S10 are repeated using only the second interference parameter. If it is determined in step S10 that the (multiple) conditions regarding the quality metric are satisfied, then step S11 is executed. If the (multiple) conditions regarding the quality metric are not satisfied, steps S5 to S10 are run again as described above (sequentially implemented) until step S11 can be executed.

[0204] According to another embodiment of the method of the invention, it is provided that when executing steps S5 to S10, multiple interference parameters are taken into account simultaneously. For example, if the interference function has a first interference parameter and a second interference parameter, when executing steps S5 to S10, the first interference parameter and the second interference parameter are set / modified simultaneously in step S5. Steps S6 to S10 are then executed. If it is determined in step S10 that the condition(s) regarding the quality metric are not met, steps S5 to S10 are run again. In this case, both the value of the first interference parameter and the value of the second interference parameter are set or modified. Then, steps S6 to S10 are repeated using the first interference parameter and the second interference parameter. If it is determined in step S10 that the condition(s) regarding the quality metric are met, step S11 is then executed. If the condition(s) regarding the quality metric are not met, steps S5 to S10 are run again until step S11 can be executed.

[0205] The primary electron beam of the SEM 100 may be affected by a variety of disturbances. Each of these disturbances can be described by a corresponding disturbance function. As described above, the disturbed measurement grid is thus generated as follows:

[0206]

[0207] In the formula, and are the coordinates of the i-th scan point (i.e., the actual scan point) among the N scan points in the disturbed measurement grid. In an alternative, it is provided that multiple interferences are described in a single interference function, where the total number of variables to be optimized (i.e., interference parameters) increases multiplicatively. For example, the optimization of the interference parameters (i.e., performing or repeating steps S5 to S10) can be implemented simultaneously for all interference parameters to be considered in the sole interference function of the current interference or all interference functions. In other words, all interference parameters are set / modified in step S5. Subsequently, steps S6 to S10 are run until step S11 can be performed. If it is determined within the scope of step S10 that steps S5 to S10 need to be run again, then when repeating step S5, all interference parameters are set / modified again. In another embodiment, it is provided that the interference parameters of the sole interference function of the current interference or all interference functions are optimized successively in each case. For example, for this purpose, an order of the interference parameters to be optimized is predetermined. Then, the interference parameters of the interference function or all interference functions are optimized successively according to the predetermined order. In other words, the interference parameters are each used to perform or repeat steps S5 to S10 according to their order. In still other words, the first interference parameter according to the order is initially used to perform steps S5 to S10. Therefore, this first interference parameter is initially modified / set in step S5. Subsequently, steps S6 to S10 are performed. If step S11 still cannot be performed, then when repeating steps S5 to S10, the next interference parameter according to the predetermined order is used. The interference parameters are used according to the predetermined order until step S11 can be performed.

[0208] For example, the optimized interference parameters remain fixed during the optimization of the non-optimized interference parameters. In other words, the optimized interference parameters are no longer modified. In an alternative, it is provided that when the non-optimized interference parameters are optimized preferentially, the already optimized interference parameters are also optimized again. For example, the predetermined order can be based on the expected degree of influence on the corrected image and / or based on the frequency of the corresponding generated interference.

[0209] If the number of interferences affecting the primary electron beam of the SEM 100 cannot be accurately known, then according to one embodiment of the method according to the invention, the optimization is carried out according to a sequential method. In other words, first, one or more interference parameters of the first interference function of the first interference are optimized as has been further described above. Subsequently, it is tested whether the primary electron beam is affected by additional interferences that should be considered. In an alternative, if the user determines that the image correction is insufficient, the user himself can add an interference function to the method according to the invention. If additional interferences are considered, one or more interference parameters of the additional interference function of this additional interference are considered and optimized. For example, an interference (e.g., in the form of an interference function) can be added until a corrected image with sufficient image quality for the user can be obtained. In the above embodiment, for example, the optimized interference parameters remain fixed during the optimization of the non-optimized interference parameters. In other words, the optimized interference parameters are not modified anymore. In an alternative, it is provided that when the non-optimized interference parameters are optimized, the already optimized interference parameters are also optimized again.

[0210] Another embodiment of the method according to the invention provides that the scanning region is subdivided into a plurality of regions, and the method according to the invention is carried out for each of the plurality of regions with respect to the optimization of one or more interference parameters. Figure 5 This embodiment of the method according to the invention for a first partial region (hereinafter referred to as the first scanning region) of the scanning region of the object 125 is shown. Further, Figure 6 This embodiment of the method according to the invention for a second partial region (hereinafter referred to as the second scanning region) of the scanning region of the object 125 is shown. According to Figure 5 and Figure 6 The embodiment is based on the embodiment according to Figure 4 Reference is made to the explanations given above, which also apply here. Then, the corresponding optimized values of the interference parameters obtained according to the embodiments of Figure 5 and Figure 6 are used to create a corrected image of the entire scanning region of the object 125. For example, the average value of the optimized values of one or more interference parameters over the plurality of regions (i.e., in the embodiments described here, over the first scanning region and the second scanning region) is determined, or the optimized values of one or more interference parameters are interpolated according to the detection time.

[0211] According to yet another embodiment of the method according to the invention, it is provided that one or more interference parameters are optimized using, in particular, only a subset of the desired scan points. In this context, the subset forms, for example, a partial area of the scan area. In an alternative, the subset is distributed, for example, regularly or irregularly over the entire scan area of the object 125. In this context, it is advantageous that the interference of the primary electron beam occurs in the area of the subset of the desired scan points in order to obtain a meaningful optimization. For example, the subset of the desired scan points is selected such that intensity variations occur due to the object structures present in the subset. In particular, these structures are edges or corners.

[0212] According to yet another embodiment of the method according to the invention, it is provided that the quality metric is further specified in order to obtain a good corrected image. For this purpose, the quality metric is enhanced by additional regularization that evaluates the distortion remaining in the corrected image. For example, it has been taken into account that the quality metric should be determined according to Equation

[18] . Referring to the explanations given further above, these explanations also apply here.

[0213] According to yet another embodiment of the method according to the invention, it is provided that the calculation of the desired detection signal at the desired scan points is carried out by interpolation in step S7. The desired scan points, the actual scan points, and the actual detection signals are used during the interpolation. Any suitable interpolation method can be used during the interpolation, such as linear interpolation, non-linear interpolation, triangular interpolation, logarithmic interpolation, nearest neighbor interpolation, and / or spline interpolation. The invention is not limited to the above interpolation methods. Instead, any interpolation method suitable for the invention can be used. For example, the above function ψ is an interpolation operator.

[0214] Additionally or alternatively, according to yet another embodiment of the method according to the invention, it is provided that the calculation of the desired detection signal at the desired scan points is carried out by inpainting, where the desired scan points, the actual scan points, and the actual detection signals are used and taken into account during the inpainting. As already mentioned above, inpainting is a known method by which an image can be processed in such a way that missing parts of the image are reconstructed.

[0215] Figure 7 Another embodiment of the method according to the invention is shown. According to Figure 7 the embodiment is based on the embodiment according to Figure 4 Therefore, referring to the explanations given above, these explanations also apply here. In Figure 7In an embodiment of the method according to the present invention as shown, when controlling at least one of the above guiding devices 102, 103, 105, 106, 108, 111, 112, 113, 115 and / or 122, predetermined guiding parameters are used. When using the first value of the guiding parameter, the primary electron beam of the SEM 100 is guided in a first manner. In contrast, when using the second value of the guiding parameter, the primary electron beam of the SEM 100 is guided in a second manner. For example, the guiding parameter is (i) the residence time of the primary electron beam of the SEM 100 at a predetermined position of the object 125 or (ii) the retrace time of the primary electron beam of the SEM 100 from a first position on a scan line to a second position on the scan line, where the primary electron beam of the SEM 100 is guided along the scan line. The guiding parameter is not limited to the above embodiment. Instead, any parameter suitable for the present invention can be used as the guiding parameter. Compared with the embodiment of the method according to the present invention according to Figure 4 The embodiment of the method according to the present invention according to Figure 7 includes, for example, another step S1A performed between step S1 and step S2. In step S1A, predetermined particle beam parameters are used when controlling the control device 123. When using the first value of the particle beam parameter, the primary electron beam of the SEM 100 has a first beam characteristic. In contrast, when using the second value of the particle beam parameter, the primary electron beam of the SEM 100 has a second beam characteristic. For example, the following items at a predetermined position of the primary electron beam of the SEM 100 on the object 125 are used as the particle beam parameter: the current intensity of the primary electron beam of the SEM 100, the electron energy of the primary electron beam of the SEM 100, or the range of the primary electron beam of the SEM 100. The particle beam parameter is not limited to the above embodiment. Instead, any parameter suitable for the present invention can be used as the particle beam parameter. Further, this embodiment of the method according to the present invention provides that when guiding the primary electron beam of the SEM 100 on the scanning area of the object 125, the first value and / or the second value of the guiding parameter and the first value and / or the second value of the particle beam parameter are used.

[0216] Using according to Figure 7According to an embodiment of the method of the present invention, for example, when controlling at least one of the above guiding devices 102, 103, 105, 106, 108, 111, 112, 113, 115, and / or 122, a predetermined first guiding parameter and a predetermined second guiding parameter can be used. The first guiding parameter is different from the second guiding parameter. For example, the first guiding parameter is (i) the first dwell time of the primary electron beam of the SEM 100 at a predetermined position of the object 125 or (ii) the first retrace time of the primary electron beam of the SEM 100 from a first position to a second position on a scan line, where the primary electron beam of the SEM 100 is guided along the scan line. The first guiding parameter is not limited to the above embodiment. Instead, any parameter suitable for the present invention can be used as the first guiding parameter. In addition, for example, the second guiding parameter is (i) the second dwell time of the primary electron beam of the SEM 100 at a predetermined position of the object 125 or (ii) the second retrace time of the primary electron beam of the SEM 100 from a first position to a second position on a scan line, where the primary electron beam of the SEM 100 is guided along the scan line. The second guiding parameter is not limited to the above embodiment. Instead, any parameter suitable for the present invention can be used as the second guiding parameter. Further, what this embodiment provides is that in step S1A, a predetermined first particle beam parameter and a predetermined second particle beam parameter are used when controlling the control device 123. The first particle beam parameter and the second particle beam parameter are different from each other. When the first particle beam parameter is used, the primary electron beam of the SEM 100 has a first beam characteristic. In contrast, when the second particle beam parameter is used, the primary electron beam of the SEM 100 has a second beam characteristic. For example, the following items at a predetermined position of the object 125 by the primary electron beam of the SEM 100 are used as the first particle beam parameter: the first current intensity of the primary electron beam of the SEM 100, the first electron energy of the primary electron beam of the SEM 100, or the first range of the primary electron beam of the SEM 100. The first particle beam parameter is not limited to the above embodiment. Instead, any parameter suitable for the present invention can be used as the first particle beam parameter. Further, for example, the following items at a predetermined position of the object 125 by the primary electron beam of the SEM 100 are used as the second particle beam parameter: the second current intensity of the primary electron beam of the SEM 100, the second electron energy of the primary electron beam of the SEM 100, or the second range of the primary electron beam of the SEM 100. The second particle beam parameter is not limited to the above embodiment. Instead, any parameter suitable for the present invention can be used as the second particle beam parameter. In addition, what this embodiment of the method according to the present invention provides is that when guiding the primary electron beam of the SEM 100 on the scan area of the object 125, the first guiding parameter and the first particle beam parameter are first used, and then the second guiding parameter and the second particle beam parameter are used to generate a plurality of images.In an alternative, it is provided that when guiding the primary electron beam of the SEM 100 over the scanning area of the object 125, the first guiding parameters and the second particle beam parameters are used first, and then the second guiding parameters and the first particle beam parameters are used, in order to generate a plurality of images.

[0217] For example, according to Figure 7 an embodiment of the method according to the invention provided is that generating the actual image in step S4 includes using the control device 123 to generate a first series of a plurality of images of the scanning area and a second series of a plurality of images of the scanning area. In this context, in particular, it is provided that the above-mentioned first guiding parameters and the above-mentioned first particle beam parameters are used when generating the first series of a plurality of images of the scanning area. Further, in particular, it is provided that the above-mentioned second guiding parameters and the above-mentioned second particle beam parameters are used when generating the second series of a plurality of images of the scanning area. In an alternative, for example, it is provided that the above-mentioned first guiding parameters and the above-mentioned second particle beam parameters are used when generating the first series of a plurality of images of the scanning area. Further, in particular, it is provided that the above-mentioned second guiding parameters and the above-mentioned first particle beam parameters are used when generating the second series of a plurality of images of the scanning area.

[0218] For example, another embodiment of the method according to the invention provided is that when performing step S11(c), when the control device 123 controls at least one of the guiding devices 102, 103, 105, 106, 108, 111, 112, 113, 115 and / or 122 further mentioned above, a disturbance function with disturbance parameters is used in such a way that the disturbance parameters have the same value when guiding the primary electron beam of the SEM 100 to the first scanning point among the desired scanning points and when guiding the primary electron beam of the SEM 100 to the second scanning point among the desired scanning points. For example, a phase with the same value is used as the disturbance parameter. This embodiment of the method according to the invention is based on the following consideration: Whenever the disturbance occurring in each case has the same disturbance parameter (for example, the same phase value), the primary electron beam of the SEM 100 is always guided to the first scanning point among the desired scanning points and the second scanning point among the desired scanning points. Eventually, the primary electron beam of the SEM 100 is synchronized with the disturbance in time. Therefore, the primary electron beam of the SEM 100 is finally disturbed in the same way at each scanning point among the desired scanning points and is accordingly deflected in the same way. Since the recorded image of the scanning area is finally shifted uniformly and the disturbance is known, a corrected image of the scanning area can be generated when the known disturbance is taken into account.

[0219] Explicitly mention the following fact: The order of the individual steps of the embodiments of the method according to the invention further explained above and / or further below is not limited to the order described for the embodiments of the method according to the invention further explained above and / or further below. Instead, any order suitable for the individual steps of the invention can be used for the method according to the invention. In addition, at least two of these steps further specified above and / or further below can also be executed in parallel with each other.

[0220] The features of the invention disclosed in this specification, the drawings and the claims may be essential for implementing the invention, either individually or in any desired combination, in different embodiments of the invention. The invention is not limited to the described embodiments. Variations are possible within the scope of the claims and taking into account the knowledge of a person skilled in the art.

[0221] List of reference numerals

[0222] 100 SEM

[0223] 101 Electron source

[0224] 102 Extraction electrode

[0225] 103 Anode

[0226] 104 Beam guiding tube

[0227] 105 First bunching lens

[0228] 106 Second bunching lens

[0229] 107 First objective lens

[0230] 108 First aperture unit

[0231] 108A First aperture

[0232] 109 Second aperture unit

[0233] 110 Pole piece

[0234] 111 Coil

[0235] 112 Single electrode

[0236] 113 Tubular electrode

[0237] 114 Object holder

[0238] 115 Scanning device

[0239] 116 First detector

[0240] 116A Backscatter grating

[0241] 117 Second detector

[0242] 118 Second aperture

[0243] 119 Chamber detector

[0244] 120 Sample chamber

[0245] 121 Third detector

[0246] 122 Sample stage

[0247] 123 Control device with a processor

[0248] 124 Monitor

[0249] 125 Object

[0250] 126 Database

[0251] 200 Combined device

[0252] 201 Sample chamber

[0253] 300 Ion beam device

[0254] 301 Ion beam generator

[0255] 302 Extraction electrode in the ion beam device

[0256] 303 Beam bunching lens

[0257] 304 Second objective lens

[0258] 306 Adjustable or selectable aperture

[0259] 307 First electrode arrangement

[0260] 308 Second electrode arrangement

[0261] 400 Particle beam device with a corrector unit

[0262] 401 Particle beam column

[0263] 402 Electron source

[0264] 403 Extraction electrode

[0265] 404 Anode

[0266] 405 First electrostatic lens

[0267] 406 Second electrostatic lens

[0268] 407 Third electrostatic lens

[0269] 408 Magnetic Deflection Unit

[0270] 409 First Electrostatic Beam Deflection Unit

[0271] 409A First Multipole Unit

[0272] 409B Second Multipole Unit

[0273] 410 Beam Deflection Device

[0274] 411A First Magnetic Sector

[0275] 411B Second Magnetic Sector

[0276] 411C Third Magnetic Sector

[0277] 411D Fourth Magnetic Sector

[0278] 411E Fifth Magnetic Sector

[0279] 411F Sixth Magnetic Sector

[0280] 411G Seventh Magnetic Sector

[0281] 413A First Mirror Electrode

[0282] 413B Second Mirror Electrode

[0283] 413C Third Mirror Electrode

[0284] 414 Electrostatic Mirror

[0285] 415 Fourth Electrostatic Lens

[0286] 416 Second Electrostatic Beam Deflection Unit

[0287] 416A Third Multipole Unit

[0288] 416B Fourth Multipole Unit

[0289] 417 Third Electrostatic Beam Deflection Unit

[0290] 418 Fifth Electrostatic Lens

[0291] 418A Fifth Multipole Unit

[0292] 418B Sixth Multipole Unit

[0293] 419 First Analysis Detector

[0294] 420 Beam Guide Tube

[0295] 421 Objective Lens

[0296] 422 Magnetic Lens

[0297] 423 Sixth electrostatic lens

[0298] 424 Sample stage

[0299] 425 Object

[0300] 426 Sample chamber

[0301] 427 Detection beam path

[0302] 428 Second analysis detector

[0303] 429 Scanning device

[0304] 432 Additional magnetic deflection element

[0305] 500 Radiation detector

[0306] 709 First beam axis

[0307] 710 Second beam axis

[0308] OA Optical axis

[0309] OA1 First optical axis

[0310] OA2 Second optical axis

[0311] OA3 Third optical axis

[0312] S1 to S11 Method steps

[0313] S1A Method step

Claims

1. A method for generating a corrected image of an object (125, 425) using a particle beam device (100, 200, 400), wherein, The method comprises the following steps: (i) Using a control device (123) of the particle beam apparatus (100, 200, 400) to control a guiding device (101, 102, 103, 105, 106, 108, 111, 112, 113, 115, 122, 301, 302, 303, 304, 306, 307, 308, 402, 403, 404, 405, 406, 407, 408, 409, 409A, 409B, 410, 411A, 411B, 411C, 411D, 411E, 411F, 411G, 413A, 413B, 413C, 415, 416, 416A, 416B, 417, 418, 418A, 418B, 422, 423, 424, 429, 432) of the particle beam apparatus (100, 200, 400) so as to direct a particle beam of the particle beam apparatus (100, 200, 400) to a desired scan point in a scan area on an object (125, 425), the particle beam comprising charged particles; (ii) Using the guiding device (101, 102, 103, 105, 106, 108, 111, 112, 113, 115, 122, 301, 302, 303, 304, 306, 307, 308, 402, 403, 404, 405, 406, 407, 408, 409, 409A, 409B, 410, 411A, 411B, 411C, 411D, 411E, 411F, 411G, 413A, 413B, 413C, 415, 416, 416A, 416B, 417, 418, 418A, 418B, 422, 423, 424, 429, 432) to direct the particle beam over the scan area of the object (125, 425); (iii) Using a detector (116, 117, 119, 121, 419, 428, 500) of the particle beam apparatus (100, 200, 400) to detect interaction particles and / or interaction radiation, the interaction particles and / or the interaction radiation being generated by an interaction of the particle beam with the object (125, 425), and using the detector (116, 117, 119, 121, 419, 428, 500) to generate a detection signal based on the interaction particles detected by the detector (116, 117, 119, 121, 419, 428) and / or the interaction radiation detected by the detector (500); (iv) Using the control device (123) to generate a plurality of images of the scan area of the object (125, 425) based on the detection signals; (v) Use the control device (123) to define an interference function having at least one interference parameter with a predetermined value, the interference function describing the interference with the path of the particle beam in the particle beam device (100, 200, 400) as compared to the path of the particle beam in the particle beam device (100, 200, 400) without interference; (vi) Use the control device (123) to calculate, by means of the interference function, the actual scan points in the scan region, which actual scan points are the scan points to which the particle beam is actually guided by the guiding device (101, 102, 103, 105, 106, 108, 111, 112, 113, 115, 122, 301, 302, 303, 304, 306, 307, 308, 402, 403, 404, 405, 406, 407, 408, 409, 409A, 409B, 410, 411A, 411B, 411C, 411D, 411E, 411F, 411G, 413A, 413B, 413C, 415, 416, 416A, 416B, 417, 418, 418A, 418B, 422, 423, 424, 429, 432) due to the interference with the particle beam, rather than these desired scan points; (vii) Use the control device (123) to calculate, by means of these actual scan points and these detection signals, the desired detection signals at these desired scan points, and generate, for the plurality of images, a desired image of the scan region of the object (125, 425) based on these desired detection signals; (viii) Use the control device (123) to compare these generated desired images, the comparison being performed by subtracting the desired detection signal of one of these desired images from the desired detection signals of the other of these desired images to generate a corresponding subtraction signal for each of these desired scan points; (ix) Calculate a quality metric depending on the interference parameter and these subtraction signals, and use the control device (123) to test (i) whether the quality metric is less than or equal to a predetermined threshold, and / or (ii) whether the quality metric does not deviate or only slightly deviates from a pre-determined quality metric, and if the quality metric is less than or equal to the predetermined threshold and / or if the quality metric does not deviate or only slightly deviates from the pre-determined quality metric, then perform one of the following steps: (a) Use the control device (123) to define the corrected image by selecting one of these desired images as the corrected image; (b) Use the interference function to calculate the corrected image, the corrected image including a region of the object (125, 425) that is different from the scan region and / or at least partially covers the scan region; (c) Using the interference function with the interference parameter to control the guiding device (123) with the control device (123) to guide the particle beam to the desired scan points in the scan region on the object (125, 425), using the guiding device (101, 102, 103, 105, 106, 108, 111, 112, 113, 115, 122, 301, 302, 303, 304, 306, 307, 308, 402, 403, 404, 405, 406, 407, 408, 409, 409A, 409B, 410, 411A, 411B, 411C, 411D, 411E, 411F, 411G, 413A, 413B, 413C, 415, 416, 416A, 416B, 417, 418, 418A, 418B, 422, 423, 424, 429, 432) to guide the particle beam to the desired scan points in the scan region of the object (125, 425), using the detectors (116, 117, 119, 121, 419, 428, 500) of the particle beam device (100, 200, 400) to detect additional interaction particles and / or additional interaction radiation, the additional interaction particles and / or the additional interaction radiation being generated by additional interactions of the particle beam with the object (125, 2. The method according to claim 1, wherein 425), using the detectors (116, 117, 119, 121, 419, 428, 500) to generate additional detection signals based on the additional interaction particles detected by the detectors (116, 117, 119, 121, 419, 428) and / or the additional interaction radiation detected by the detector (500), and using the control device (123) to generate a corrected image of the scan region of the object (125, 425) based on the additional detection signals.

3. The method according to claim 1 or 2, wherein The method includes the following steps: If the quality metric is greater than the predetermined threshold and / or if the quality metric has more than a slight deviation from the pre-determined quality metric, then change the value of the interference parameter and perform steps (vi) to (ix) again. Defining the interference function includes at least one of the following steps: - Load the interference function from the database (126) of the particle beam device (100, 200, 400) into the control device (123) of the particle beam device (100, 200, 400); - Input the interference function into the control device (123) of the particle beam device (100, 200, 400); - Use the control device (123) to predetermine the interference function; - Use the control device (123) to generate the interference function.

4. The method according to any one of the preceding claims, wherein, Defining the interference function includes: - Define the interference function as an oscillation; - Define the interference parameter as the amplitude, frequency, direction, phase or time of the interference.

5. The method according to any one of the preceding claims, wherein The interference parameter is a first interference parameter, and wherein defining the interference function further includes defining the interference function using at least one second interference parameter, the second interference parameter having a predetermined value.

6. The method according to claim 5, wherein, Use the amplitude, frequency, direction, phase or time of the interference as the second interference parameter.

7. The method according to claim 5 or 6, wherein The method includes one of the following steps: - When performing steps (vi) to (ix) according to claim 1, use the first interference parameter and the second interference parameter simultaneously; - Initially perform steps (vi) to (ix) according to claim 1 only using the first interference parameter, and subsequently perform steps (vi) to (ix) again only using the second interference parameter; - Initially perform steps (vi) to (ix) according to claim 1 only using the second interference parameter, and subsequently perform steps (vi) to (ix) again only using the first interference parameter.

8. The method according to any one of the preceding claims, wherein, The method includes at least one of the following steps: - Implement the calculation of the desired detection signals at the desired scan points by interpolation, wherein the desired scan points, the actual scan points and the detection signals are used during the interpolation; - Implement the calculation of the desired detection signals at the desired scan points by inpainting, wherein the desired scan points, the actual scan points and the detection signals are used during the inpainting.

9. The method according to any one of the preceding claims, wherein The method includes the following steps: - Use predetermined guiding parameters when controlling the guiding device (101, 102, 103, 105, 106, 108, 111, 112, 113, 115, 122, 301, 302, 303, 304, 306, 307, 308, 402, 403, 404, 405, 406, 407, 408, 409, 409A, 409B, 410, 411A, 411B, 411C, 411D, 411E, 411F, 411G, 413A, 413B, 413C, 415, 416, 416A, 416B, 417, 418, 418A, 418B, 422, 423, 424, 429, 432), wherein when using a first value of the guiding parameter, guide the particle beam in a first manner, and wherein when using a second value of the guiding parameter, guide the particle beam in a second manner; - Controlling the control device (123) using predeterminable particle beam parameters, wherein when using a first value of the particle beam parameters, the particle beam has a first beam characteristic, and wherein when using a second value of the particle beam parameters, the particle beam has a second beam characteristic; - Using the first value and / or the second value of the guiding parameters and using the first value and / or the second value of the particle beam parameters when guiding the particle beam over the scanning area of the object (125, 425).

10. The method according to any one of the preceding claims, wherein, The method comprises the steps of: - Using a predeterminable first guiding parameter and a predeterminable second guiding parameter when controlling the guiding device (101, 102, 103, 105, 106, 108, 111, 112, 113, 115, 122, 301, 302, 303, 304, 306, 307, 308, 402, 403, 404, 405, 406, 407, 408, 409, 409A, 409B, 410, 411A, 411B, 411C, 411D, 411E, 411F, 411G, 413A, 413B, 413C, 415, 416, 416A, 416B, 417, 418, 418A, 418B, 422, 423, 424, 429, 432), wherein the first guiding parameter is different from the second guiding parameter; - Controlling the control device (123) using a predeterminable first particle beam parameter and a predeterminable second particle beam parameter, wherein the first particle beam parameter is different from the second particle beam parameter, wherein when using the first particle beam parameter, the particle beam has a first beam characteristic, and wherein when using the second particle beam parameter, the particle beam has a second beam characteristic; - First using the first guiding parameter and using the first particle beam parameter, and then using the second guiding parameter and using the second particle beam parameter when guiding the particle beam over the scanning area of the object (125, 425) in order to generate the plurality of images.

11. The method according to any one of the preceding claims, wherein, When performing step (c) according to claim 1, when the control device (123) controls the guiding device (101, 102, 103, 105, 106, 108, 111, 112, 113, 115, 122, 301, 302, 303, 304, 306, 307, 308, 402, 403, 404, 405, 406, 407, 408, 409, 409A, 409B, 410, 411A, 411B, 411C, 411D, 411E, 411F, 411G, 413A, 413B, 413C, 415, 416, 416A, 416B, 417, 418, 418A, 418B, 422, 423, 424, 429, 432), the interference function with the interference parameter is used in the following manner: such that when guiding the particle beam to the first scanning point among these desired scanning points and when guiding the particle beam to the second scanning point among these desired scanning points, the interference parameter has the same value.

12. A computer program product having program code that can be loaded into a processor (123) and, when executed, controls a particle beam device (100, 200, 400) such that the method according to at least one of the preceding claims is performed.

13. A particle beam device (100, 200, 400) for processing, imaging, and / or analyzing an object (125, 425), the particle beam device having - at least one beam generator (101, 301, 402) for generating a particle beam having charged particles; - at least one guiding device (101, 102, 103, 105, 106, 108, 111, 112, 113, 115, 122, 301, 302, 303, 304, 306, 307, 308, 402, 403, 404, 405, 406, 407, 408, 409, 409A, 409B, 410, 411A, 411B, 411C, 411D, 411E, 411F, 411G, 413A, 413B, 413C, 415, 416, 416A, 416B, 417, 418, 418A, 418B, 422, 423, 424, 429, 432) for guiding the particle beam over a scanning area of the object (125, 425); - at least one detector (116, 117, 119, 121, 419, 428, 500) for detecting interaction particles and / or interaction radiation generated by the interaction of the particle beam with the object (125, 425); - at least one display device (124) for displaying an image and / or analysis of the object (125, 425); and - At least one control device (123) having at least one processor, into which the computer program product according to claim 12 is loaded.

14. The particle beam device (100, 200, 400) according to claim 13, wherein, The beam guiding device (101, 102, 103, 105, 106, 108, 111, 112, 113, 115, 122, 301, 302, 303, 304, 306, 307, 308, 402, 403, 404, 405, 406, 407, 408, 409, 409A, 409B, 410, 411A, 411B, 411C, 411D, 411E, 411F, 411G, 413A, 413B, 413C, 415, 416, 416A, 416B, 417, 418, 418A, 418B, 422, 423, 424, 429, 432) comprises at least one of the following features: - At least one objective lens (107, 304, 421) for focusing the particle beam onto the object (125, 425); - At least one scanning device (115, 429) for scanning the particle beam over the object (125, 425).

15. The particle beam device (200) according to claim 13 or 14, wherein, The beam generator takes the form of a first beam generator (101), and the particle beam takes the form of a first particle beam with first charged particles, wherein the beam guiding device takes the form of a first beam guiding device (101, 102, 103, 105, 106, 108, 111, 112, 113, 115, 122), and wherein the particle beam device (200) further comprises: - At least one second beam generator (301) for generating a second particle beam with second charged particles; and - At least one second beam guiding device (301, 302, 303, 304, 306, 307, 308) for guiding the particle beam over the scanning area of the object (125).

16. The particle beam device (200) according to claim 15, wherein, The second beam guiding device (301, 302, 303, 304, 306, 307, 308) comprises at least one of the following features: - At least one additional objective lens (304) for focusing the particle beam onto the object (125); - At least one additional scanning device (307, 308) for scanning the particle beam over the object (125).

17. A particle beam apparatus (100, 200, 400) according to any one of claims 13 to 16, wherein, The particle beam device (100, 200, 400) is an electron beam device and / or an ion beam device.

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