METHOD FOR PROCESSING AND / OR EXAMINATING A SAMPLE, COMPUTER PROGRAM AND DEVICE THEREFOR

Abstract

Method for processing and / or examining a sample (100) with a particle beam (E), comprising the steps: Determining an electrostatic charge of the sample (100); Applying a voltage to an element (H) in an environment of the sample based at least in part on the determined electrostatic charge; wherein the element (H) comprises two or more segments; and where the application of the voltage comprises: Applying a first voltage to a first segment (1, P1) of the element (H); Applying a second voltage to a second segment (2, P2) of the element (H).

Description

1. Technical FieldThe present invention relates to a method for processing and / or examining a sample with a particle beam, and to a corresponding computer program and a device.2. Background ArtThe processing and / or examination of a sample with a particle beam has been known for a long time. For example, the particle beam can comprise an electron beam, ion beam and / or a photon beam, which is provided on the sample in a defined manner for examining and / or processing the sample. With the provision of the particles of the particle beam on the sample, different interactions can be generated, which can enable different processing processes and / or examinations of the sample. Particle beam-based processing and / or examination of a sample can thus comprise a wide variety of methods.For example, the particle beam-based processing can comprise a particle beam-induced etching and / or deposition, in which material of a sample is locally removed or generated. This may include e.g. electron beam induced etching and / or deposition. Furthermore, for example, a defined photon irradiation of the sample may also be necessary for processing the sample (e.g. in the case of a laser-induced reaction). The examination of a sample with a particle beam can comprise, for example, an image recording of the sample with the aid of the particles of the particle beam (for example, as is carried out with the aid of an electron beam in a scanning electron microscope).Particle beam-based processing and / or examination of a sample with a particle beam is meanwhile used in industry for various applications.Thus, for example, in the semiconductor industry, increasingly smaller structures are produced on a wafer in order to ensure an increase in the integration density. For the production of the structures, lithographic methods are used, among other things, which image them on the wafer. The lithographic methods may include, for example, photolithography, ultraviolet (UV) lithography, DUV lithography (i.e., deep ultraviolet (UV) lithography), EUV lithography (i.e., extreme ultraviolet (UV) lithography), X-ray lithography, nanoimprint lithography, etc. In this case, masks are usually used as objects for lithography (e.g. photomasks, exposure masks, reticles, stamps in nanoimprint lithography, etc.), which comprise a pattern in order to image the desired structures on a wafer, for example.As the integration density increases, mask fabrication requirements also increase (e.g., due to the concomitant reduction in feature sizes on the mask or due to the higher material requirements of lithography). The fabrication processes of the masks thus become increasingly complex, time-consuming and cost-intensive. Mask defects (e.g., defects) cannot always be avoided. Usually, the mask defects are therefore repaired by particle beam-based processing, since these can be repaired, for example, only on a particle beam basis because of their small dimensions.Furthermore, it may be necessary, for example in the semiconductor industry, to examine samples with a particle beam. For example, for the repair of mask defects described herein, it may be necessary to perform image recordings of the mask defects or of the repair location using a particle beam (for example for a high-resolution scanning electron microscope image).It may also be necessary for other industrial purposes to process and / or examine a sample with a particle beam. For example, this may be done for the analysis (e.g. fault analysis) of a sample, which may e.g. comprise a microchip, a wafer, a biological sample, etc.The samples to be processed and / or examined with the particle beam can, however, have an (undesired) electrostatic charge. The (undesired) electrostatic charge can be locally limited on the sample, for example. However, it is also possible for the (undesired) electrostatic charge to be present, for example, globally above the sample.Undesired effects can be caused by the (undesired) electrostatic charge. For example, the (undesired) electrostatic charge can adversely affect the properties of the particle beam impinging on the sample in an undesired manner. For example, the (undesired) electrostatic charge can lead to the particle beam being unintentionally deflected from the intended point of impingement on the sample. Furthermore, the electrostatic charge can lead, for example, to a particle beam-based reaction not achieving the desired effect. The (undesired) electrostatic charge therefore does not always ensure the defined processing and / or examination of the sample in an optimum manner.Usually, therefore, for a defined processing and / or examination of the sample with a particle beam, technical handling must be done with the effects caused by the electrostatic charge of the sample.U.S. Pat. No. 6,664,546 B1 relates to a method and an apparatus for generating an image from a sample. The apparatus comprises a charged particle beam generator arranged to generate and control a charged particle beam substantially towards a portion of the sample, and a detector arranged to detect charged particles originating from the sample portion to enable the generation of an image from the detected charged particles. The apparatus also comprises a measuring device for measuring a property of the sample section in order to obtain a surface tension value of the sample section which is exposed to the charged particle beam. For example, the measurement device is an electrostatic voltmeter positioned to sense a surface voltage value of the exposed sample portion. Under a first set of operating conditions, a beam of charged particles is directed substantially onto a portion of the sample. Under the first operating conditions, a surface charge value of the sample section is determined. It is then determined whether an optimum set of operating conditions has been found in connection with a predetermined surface charge value.US 2012 / 0 119 085 A1 is concerned with the problem of carrying out charge measurement or focusing of a sample with high speed and high precision also for such a sample in which fixed charge and induced charge may be present in a mixed manner. As a means for solving this problem, there are proposed a method for measuring the sample potential and an apparatus for carrying out the method, which are characterized in that when sample potential information obtained from a first sample potential measurement device disposed outside a sample chamber or sample potential information obtained in advance is equal to or greater than a predetermined threshold value or is above the threshold value, the measurement of the sample potential is selectively carried out by a second sample potential measurement device in the sample chamber.US 2014 / 0 027 635 A1 relates to a charged particle beam apparatus adapted such that even if no additional apparatus is mounted in the charged particle beam apparatus, the apparatus rapidly removes a local charge developed in a region of a sample irradiated with a charged particle beam by neutralization. After irradiation of the sample with a charged particle beam for measurement, the apparatus controls a retardation voltage and / or an acceleration voltage at a stage before a next measurement, and then neutralizes an electric charge by reducing a difference between a value of the retardation voltage and that of the acceleration voltage to a value smaller than during the currently running measurement.US 2021 / 0 043 420 A1 describes a scanning electron microscope. The scanning electron microscope includes an electron optical system including an electron source and an objective lens, a stage on which a sample is placed, a secondary electron detector disposed adjacent to the electron source with respect to the objective and configured to detect secondary electrons, a backscattered electron detector disposed between the objective and the stage and configured to detect backscattered electrons, a controller for the backscattered electron detection system configured to apply a voltage to the backscattered electron detector, and a device control computer configured to detect a state of an electric charge carried by the backscattered electron detector based on the signal intensity at the secondary electron detector when the primary electrons are applied to the sample and a predetermined voltage is applied to the backscattered electron detector.JP 2009-246 012 A relates to a method for measuring a charged potential voltage, by which a charged potential voltage can be measured on the surface of an insulating film of a sample (for example a semiconductor substrate) comprising at least one layer of an insulating film. In the method, an electron beam is irradiated on the surface of the insulating film through a thin metal film, and a sample current is measured when the electron beam is irradiated on the surface of the insulating film. Then, a sample voltage corresponding to a sample current provided using a relationship (calibration curve) between an applied voltage and a sample current is obtained, and is obtained by changing a voltage applied to the sample within a predetermined range.There is thus a need to improve the processing and / or examination of samples with a particle beam.3. SUMMARY OF THE INVENTIONThis need is met, at least in part, by the various aspects described herein.A first aspect relates to a method for processing and / or examining a sample with a particle beam, comprising the steps of: determining an electrostatic charge of the sample; applying a voltage to an element in a vicinity of the sample based at least in part on the determined electrostatic charge.On the one hand, therefore, when processing and / or examining the sample, an active determination of the electrostatic charge of the sample can be carried out. For example, the electrostatic charge of the sample can be determined on the basis of reference structures which are analyzed with the particle beam. For example, the electrostatic charge may be determined based on one or more reference structures (e.g., drift marks) located on the sample. In one example, the method also includes generating reference structures for determining the electrostatic charge of the sample. Based on a reference position of the one or more reference structures, an electrostatic charge of the sample can be determined, for example, on the basis of the current position of the one or more reference structures. Drift markings which are used as reference structures can have been deposited on the sample, for example, in order to correct the drift of a particle beam. Furthermore, any other desired ways of determining an electrostatic charge of the sample are also conceivable (for example via other types of reference structures, via a measurement of the charge and / or via an analysis of an image recording with the particle beam, etc.).On the other hand, on the basis of this information (i.e. the determined electrostatic charge), a corresponding voltage can be applied to an element in the environment of the sample. The voltage applied to the element can be selected, for example, in such a way that the particle beam influences the processing and / or examination of the sample.For example, the voltage can be selected such that a charging effect which acts on the particle beam as a result of the determined electrostatic charge can be addressed in a targeted manner during the processing and / or examination of the sample with the particle beam.For example, for processing and / or examining the sample, the particle beam can be directed onto the sample with a defined set of one or more particle beam properties. The set can comprise, for example, one or more conventional particle beam properties which are set during the processing and / or examination. For example, a particle beam property can comprise a landing energy of the particles of the particle beam on the sample, an impact position of the particles of the particle beam on the sample, a particle beam current, a particle beam acceleration, a focusing of the particle beam, and / or further types of particle beam properties. By means of the set of one or more particle beam properties, it is also possible, for example, to cause corresponding properties of particles which are released during the processing and / or examination by the particle beam provided on the sample. These particles may also be referred to herein as released particles. For example, a property of the particles released by the particle beam can be adjusted via the set of particle beam properties.However, the presence of the electrostatic charge of the sample can influence the defined set of particle beam properties and / or a property of the released particles. The electrostatic charge of the sample can cause, for example, an electric field which originates from the sample, wherein this electric field can interact with the particles of the particle beam and / or with the released particles.By means of the electric field of the electrostatic charge, for example, a present particle beam property can deviate from the set particle beam property. The electric field can, for example, accelerate or decelerate the particles there (locally) in the region of the point of impingement of the particles on the sample. For example, the electric field can also undesirably deflect the particle beam. Thus, the particle beam can, for example, not impinge on the set desired position of the sample due to the electrostatic charge, but rather at another point.The electric field of the electrostatic charge can also interact with the released particles, for example. The released particles can also be (locally) accelerated or decelerated, for example, by the electric field of the electrostatic charge.It is also conceivable that the electric field of the electrostatic charge may cause a (e.g. undesired) interaction with a particle beam-induced reaction, for which the particle beam is provided for processing on the sample (e.g. for a particle beam-induced etching and / or deposition, e.g. excess or missing material of the sample).In one example, the method can comprise: providing a gas for removing a material of the sample and / or depositing a material on the sample with the particle beam. The processing of the sample with the particle beam described herein can comprise e.g. a particle beam-induced removal (e.g. an etching reaction) and / or a particle beam-induced deposition (e.g. deposition reaction) with a corresponding gas (e.g. an etching gas or a deposition gas). In providing the gas to remove and / or deposit material, a voltage may be applied to the element based at least in part on the determined electrostatic charge (as described herein).As a result of the electrostatic charging of the sample, charge effects can therefore arise, which allow the processing and / or examination of the sample to take place differently in many ways than is actually set (or expected). The method described herein, on the other hand, can make it possible for the present electrostatic charge to be taken into account during the processing and / or examination with the particle beam and to be addressed via the element.Thus, in general, by applying the voltage to the element based on the determined electrostatic charge, a further degree of freedom can be created in the processing and / or examination of samples with a particle beam.The mentioned approach can be considered qualitatively, for example. The voltage across the element may be selected, for example, with respect to the determined electrostatic charge, such that processing and / or testing of the sample is better (than without applying the voltage across the element). For example, a presence of an electrostatic charge may have been determined. Subsequently, a voltage can be applied to the element until the result of the processing and / or examination has been optimized. For example, this can be carried out during the examination of the sample (e.g. via an image recording with the particles of the particle beam). In such a case, according to an embodiment, the electrostatic charge can be determined e.g. via image distortion, wherein the voltage on the element is adapted until a better image is obtained. Thus, based on the status of the electrostatic charge, the voltage across the element may be changed.However, the aforementioned approach can also be carried out more specifically. For example, determining the electrostatic charge may include determining a value of the electrostatic charge of the sample. The voltage applied to the element may depend, for example, on the determined value of the electrostatic charge. For example, in the case of a first electrostatic charge of C 1, a corresponding voltage U 1 can be applied to the element. In a second electrostatic charge of C2, a corresponding voltage U2 (which is different from U1) can be applied to the element.For example, the applied voltage may also depend on a range in which a specific value of the electrostatic charge of the sample falls. For example, at an electrostatic charge value that is in a first range (e.g., between values X1and X2), a corresponding voltage U1may be applied to the element. For example, at a value of the electrostatic charge that is in a second range (e.g., between values X 3 and X 4), a corresponding voltage U 2 (different from U 1) may be applied to the element.In one example, a voltage can be applied, such that a defined particle beam property of the particle beam is present at the point of incidence of the sample. For example, a counter-control can be carried out via the voltage on the element, which minimizes (or compensates) the charging effects of the electrostatic charge of the sample described herein. By means of the counter-control it can be ensured, for example, that a particle beam property has the desired value at the point of impingement, although an electric field (caused by the electrostatic charge of the sample) actually influences this particle beam property. For example, during processing and / or examination, a first particle beam property of the particle beam may have been set with a value of T 1 (e.g. via a corresponding configuration of a particle beam apparatus). Due to the electrostatic charge, however, this first particle beam property has a value at the point of impingement of the sample which is different from T 1. In this regard, counter-control can be performed via the element. A voltage can thus be applied to the element based on the present electrostatic charge, so that the first particle beam property at the point of impingement of the sample nevertheless has the value T 1. Thus, for example, with the approach described herein, the configuration of the particle beam device does not have to be adapted in order to carry out a successful counter-control. Rather, it may be sufficient to carry out the desired correction (or counter-control) of the particle beam via the voltage at the element with regard to the determination of the electrostatic charge of the sample.For example, the interaction with the released particles can also be adapted via the voltage on the element with regard to the determined electrostatic charge. The counter-control described herein can thus also be used for the released particles.For example, the particle beam-induced reaction can also be adapted via the voltage at the element, for which the particle beam is provided for processing on the sample with regard to the determined electrostatic charge. The counter-control described herein can therefore also be used for a particle beam-induced reaction.For example, in known approaches, no counter-control is performed via an element in the environment of the sample. Rather, the particle beam is changed simply (a priori), for example by a corresponding setting of the particle beam device which provides the particle beam. In this case, it can be made possible for the desired particle beam property to be present at the point of impingement of the sample, although an electric field (caused by the electrostatic charge) is present there. The particle beam is, as it were, held incorrectly on the sample, so that it nevertheless lands correctly on the sample due to the charge effects of the electrostatic charge. In known approaches, the electrostatic charge is determined, for example, by means of drift markings. The particle beam is then directed onto the sample using this information with other particle beam properties, so that ultimately the desired particle beam properties are present at the point of incidence of the sample.The method described herein, on the other hand, may provide an alternative to dealing with charging effects of electrostatically charged samples. For example, the method described herein makes it possible to dispense with complex readjustment of a particle beam apparatus which provides the particle beam. According to the method described herein, it may be sufficient to address, via the applied voltage on the element, the effects of the electrostatic charge of the sample during the processing and / or examination. However, the method described herein can also be combined with other methods which technically take into account the electrostatic charge of the sample by changing the particle beam.For example, the electrostatic charge may have been caused by the provision of the particle beam on the sample during the processing and / or examination.Thus, by providing a particle beam on a sample, a positive, negative or neutral electrostatic charge of the sample can be effected. The basic mechanism can be understood, for example, to be that two charge flows are generated which can influence the net charge of the electrostatic charge of the sample. On the one hand, the particle beam provided on the sample optionally introduces a charge into the sample (as the first charge flow). On the other hand, this can cause a reaction in the sample in which charge can remove from the sample (as the second charge flow). Thus, a net net resulting charge of the sample (local or global) can be caused.It can therefore be assumed during the processing and / or examination of a sample with a particle beam that the sample possibly charges electrostatically. According to the method described herein, for example, the electrostatic charge can be determined at any point in time during the processing and / or examination and a corresponding counter-control can be carried out via the application of the voltage to the element. The method described herein can thus represent, for example, a dynamic consideration of the state of the electrostatic charge of the sample. A change over time in the electrostatic charge during the processing and / or examination can finally be made possible with the method described herein. The method described herein may differ from a static adaptation for the correction of a particle beam, which is applied, for example, over the entire process of processing and / or examination.In one example, the method comprises processing and / or examining the sample with the particle beam before determining the electrostatic charge of the sample and applying the voltage to the element based at least in part on the determined electrostatic charge. In this case, the electrostatic charge may have been caused, for example, by the processing and / or examination of the sample with the particle beam. Subsequently (after the determination of the electrostatic charge and the application of the voltage), for example, processing and / or examination with the particle beam can be carried out again.In one example, the application of the voltage may cause an electric field at a point of impingement of the particle beam on the sample. The element can be arranged, for example, in the vicinity of the sample, such that a voltage applied to the element causes an electric field at the point of impingement of the particle beam on the sample. By the arrangement of the element and the voltage applied thereto, this electric field can be configured such that an influence on the particles of the particle beam and / or of released particles can take place. The electric field may be sufficient, for example, to minimize (or compensate for) the charging effects of the electrostatic charge of the sample described herein. The electric field emanating from the element can enable, for example, a defined particle beam property at the point of impingement of the particle beam on the sample based on the electrostatic charge of the sample.In one example, the voltage can be applied in such a way that an influencing of a landing energy of particles of the particle beam on the sample is caused. For example, the electric field caused by the electrostatic charge (starting from the sample) can change the landing energy of the particles on the sample. For example, electrostatic charging may increase or decrease landing energy.By applying the voltage, an additional electric field can in turn be caused at the point of impingement of the particles, which can likewise influence the landing energy of the particles there. The electric field caused by the element can, for example, compensate for undesired changes in the landing energy due to the electrostatic charge in a targeted manner and thus lead to the desired landing energy.In one example, the voltage can be applied in such a way that the landing energy lies in a first predetermined value range. For example, the landing energy of the particles of the particle beam can be set to a specific value (which is within the predetermined value range, for example) based on the determined electrostatic charge of the sample via the applied voltage. For example, this does not necessarily require an adaptation of the particle beam device which provides the particle beam. For example, a change in the landing energy can take place merely by applying the voltage to the element, such that the value of the desired landing energy is present.The following example can be used for this purpose. First, for example, no (appreciable) electrostatic charge of the sample can be present. During the processing and / or examination of the sample, a desired landing energy can thus be set by setting particle beam properties (e.g. by means of a particle beam apparatus). However, electrostatic charging of the sample may occur during the course of processing and / or examination. The resulting electric field may, for example, reduce or increase the landing energy of the particles. The current landing energy can thus deviate from the originally selected landing energy. By applying the voltage to the element based on the determined electrostatic charge, a change in the landing energy can be caused, so that the current landing energy again corresponds to the originally selected landing energy. It is also conceivable that by applying the voltage to the element, a landing energy can be set which was not previously applied in the method. For example, it may be useful for a method to vary the landing energy. The method described herein can therefore also be used, for example, to change the landing energy in the course of the method, which can be effected with regard to the present electrostatic charging of the sample. For this purpose, for example, only a change in the voltage across the element is required.In one example, the voltage can be applied in such a way that the electrostatic charge of the sample is at least partially compensated. For example, an electrostatic charge of the sample can be present locally (or globally), due to e.g. a local (or global) accumulation of charge carriers. This accumulation can cause a corresponding electric field. This may be referred to herein as a charge field, for example. The voltage can be applied to the element in this respect in such a way that an additional electric field is in turn caused. This may be referred to herein as a compensation field. The voltage across the element may be selected such that the compensation field may at least partially weaken the charge field. For example, a field vector of the compensation field may be oppositely directed to a field vector of the charge field such that the field vector of the charge field is reduced.Adjusting the voltage on the element thus need not be limited to influencing the landing energy of the particles. Local (or global) charging effects of the sample can also be addressed with the voltage applied to the element. For example, disturbing charging effects that influence the particle beam can thus be minimized or compensated.In one example, the electrostatic charge can lie in a second predetermined value range by applying the voltage. For example, a defined electrostatic charge of the sample can also be induced by applying the voltage to the element. By applying the voltage, for example, a positive, negative or neutral (local or global) electrostatic charge of the sample can be generated based on the determined electrostatic charge.In one example, the landing energy of the particles and the electrostatic charge of the sample may be affected by the method described herein. For example, the landing energy of the particles can be adjusted once and the electrostatic charge of the sample can be adjusted once. It should be noted that these settings may overlap. For example, adjusting the landing energy of the particles may also change the electrostatic charge of the sample. However, in such a case, the application of the voltage may be mainly directed to optimizing the landing energy. For example, adjusting the electrostatic charge of the sample may also change the landing energy of the particles. However, in such a case, the application of the voltage may be mainly directed to optimizing the electrostatic charge. In one example, it is also conceivable that the application specifically adjusts the landing energy of the particles and also the electrostatic charge of the sample. Thus, the landing energy of the particles and the electrostatic charge of the sample can be optimized. In this regard, reference is also made to the further examples described herein, in which, for example, two or more segments are used in the element.In one example, the steps of the method of the first aspect may be repeated at least once. For example, determining the electrostatic charge and applying the voltage to the element based on the electrostatic charge may be understood as a sequence of the method. This sequence may be repeated one or more times during the process. It should be noted that other steps (e.g. processing and / or examining the sample) can also take place within a sequence between the mentioned determination of the electrostatic charge and the application of the voltage. Also, other steps may take place within a sequence before determination and / or after placement.Reference is made to the following example. First, the sample can be processed and / or examined using the particle beam. The processing and / or examination may be interrupted, e.g. after a predetermined time. A first sequence comprising the determination of the electrostatic charge and the application of the voltage can then take place. In this case, for example, a first voltage can be applied with regard to the electrostatic charge of the sample determined in the first sequence. Subsequently, the sample can be processed and / or examined again using the particle beam. For example, the processing and / or examination can be continued. The processing and / or examination can be interrupted again, e.g. after a predetermined time. A second sequence comprising the determination of the electrostatic charge and the application of the voltage can then take place. In this case, for example, a second voltage can be applied (which can be different from the first voltage) with regard to the electrostatic charge determined in the second sequence.In some examples, a sequence comprising determining the electrostatic charge and applying the voltage may occur before starting processing and / or testing the sample.In one example, the element can be arranged on an underside of the sample, which lies opposite an upper side of the sample, from which the particle beam is directed onto the sample during the processing and / or examination. In the method, the particle beam would thus be incident on the sample from the top side. For example, an aperture of the particle beam and / or the particle source of the particle beam can be arranged on the top side of the sample. The top side can also comprise, for example, the surface of the sample which is processed and / or examined with the particle beam. This surface may also be referred to herein as the upper surface of the sample.In this example, the element can be arranged on the underside of the sample. For example, the underside of the sample can therefore comprise a side from which the particle beam is not incident on the sample during processing and / or examination. On the bottom side, mechanisms can be present, for example, to position the sample. The underside can also comprise, for example, the surface of the sample which is not processed and / or examined with the particle beam. This surface may also be referred to herein as the bottom surface of the sample.This arrangement of the element can have the advantage that the element does not interfere with the incident particle beam. A disturbance of the particle beam or a complex configuration of the element, which allows the particle beam to pass unimpeded, can thus be avoided. Nevertheless, the element can be arranged in a vicinity of the sample by the positioning on the underside, such that the electric field emanating from the element can reliably act on the point of impingement of the particle beam (as described herein). For example, the electric field emanating from the element can act from the underside through the sample on the point of incidence of the particle beam.In one example, there may be a gap between the element located at the bottom of the sample and the sample itself.In one example, upon application of the voltage, at least a portion of the sample may be in contact with the element. For example, the element can be arranged on the underside of the sample, wherein at least one partial surface of the sample is in contact with the element. The sample can thus be connected to the element arranged on the underside. For example, at least a partial surface of the lower surface of the sample may be in contact with the member.With this arrangement, the element can thus be brought into the environment of the sample with little complexity and can be held there in a fixed position with respect to the sample, for example with little effort.In one example, the element may comprise a holder for holding the sample and / or be part of a holder for holding the sample. The holder can be configured, for example, to position the sample within a particle beam apparatus. The holder can comprise, for example, a sample stage and / or a chuck.In one example, the element may also comprise a part of a holder for holding the sample. The element can be integrated, for example, within a holder.Generally, the element may include at least one electrode to which the voltage is applied based on the determined electrostatic charge.In one example, the holder and / or the element can comprise a base surface which is in contact with the sample during the method. For example, the sample can rest on the base surface. For example, the lower surface of the sample may be in contact with the base of the holder and / or the element. The lower surface of the sample can be smaller than the base surface of the holder.In one example, an electric field may exit the ground surface via application of the voltage to the element. For example, the base surface can be configured as an electrode (electrically conductive), so that an electric field is generated by the base surface when the voltage is applied. It is also conceivable for the element (e.g. an electrode) to be installed in the holder below a base surface (e.g. electrically non-conductive), wherein an electric field can likewise emerge from the base surface when the voltage is applied to the element. In these examples, an electric field can thus be applied to the lower surface of the sample via the base surface (of the holder). This electric field may be substantially the same at every point of the lower surface, for example. Thus, the application of the voltage globally allows the sample to be exposed to an electric field emanating from the element.As described herein, this global electric field can be used to influence the particle beam during the processing and / or examination of the sample on the basis of the determined electrostatic charge. For example, a landing energy of the particles on the sample can be adjusted via this global electric field. For example, an electrostatic charge of the sample can be adapted via this global electric field. It is also conceivable that a landing energy and also the electrostatic charge of the sample can be set via this field.In one example, the element may comprise two or more segments. In such an example, applying the voltage may include: applying a first voltage to a first segment of the element; applying a second voltage to a second segment of the element. For example, the first and second voltages may be applied simultaneously. In one example, the first and second voltages may be adjusted independently of each other. Segment-specific voltages can thus be set. For example, the first voltage may be different from the second voltage. However, it is also conceivable that in special cases the first voltage and the second voltage can be the same. It should be noted that the first and second voltages (as described herein) may be adjusted based at least in part on the predetermined electrostatic charge of the sample to correspondingly affect the processing and / or testing of the sample.In one example, the element may comprise three or more segments, wherein a segment-specific voltage may be applied for each segment. In one example, the element may comprise ten or more segments, wherein a segment-specific voltage may be applied for each segment. In one example, the element may comprise one hundred or more segments, where a segment-specific voltage may be applied for each segment. In one example, the element may comprise thousands or more segments, where a segment-specific voltage may be applied for each segment.As described herein, a segment specific voltage may be set at least partially to the predetermined electrostatic charge of the sample to correspondingly affect the processing and / or testing of the sample.In one example, the application of the first and second voltages for influencing the processing and / or examination of the sample can take place in a first region of the sample. For example, the first segment from the second segment may be located at locally different locations in the element. However, the first voltage at the first segment and the second voltage at the second element may be used to influence the processing and / or examination of the sample in an area of the sample, namely the first area.Thus, the electrostatic charge of the sample can be distributed inhomogeneously over the sample, for example. It may therefore not be sufficient in all cases to carry out a global influence on the element. However, the approach of segmenting the element can also take into account one or more local effects of the electrostatic charge (and can be correspondingly minimized and / or compensated).With the application of the first voltage to the first segment and the second voltage to the second segment, for example, two local charging effects can be addressed, which act on the first region. With the application of the first voltage to the first segment, a first effect of the electrostatic charge of the sample can be addressed, for example. With the application of the second voltage to the second segment, a second effect of the electrostatic charge of the sample can be addressed, for example. The first and second voltages may be selected to be counter-controlled to the first and second effects based on the determined electrostatic charge. For example, this can ensure a defined particle beam property in the first region against the background of the electrostatic charge of the sample (as described herein).In one example, the application of the first voltage can cause an influence on the landing energy of particles of the particle beam in the first region. For example, the first voltage at the first segment can cause a targeted setting of the landing energy of particles of the particle beam in the first region. The discussion for influencing the landing energy in the more general example can also be applied accordingly for influencing the landing energy in the first region. For example, the electrostatic charge for the first region can be determined. Based thereon, a first voltage may be selected such that the landing energy in the first range is in a predetermined range of values (or has a predetermined value). The first effect addressed with the first segment may thus comprise, for example, a change in landing energy in the first region due to the electrostatic charge of the sample (as described herein).In one example, determining the electrostatic charge may include: determining an electrostatic charge in a second region different from the first region, wherein applying the second voltage is based at least in part on the electrostatic charge determined in the second region.For example, the electrostatic charge for the second region can therefore be determined first. With this information, a second voltage can be selected which, when applied to the second segment, causes an influence on the particle beam in the first region.In one example, an electric field emanating from the second region can be suppressed by applying the second voltage. For example, a local charging field can originate from the second region, which can impair the particle beam in the first region. This disruptive charging field can be minimized or compensated for with the second voltage on the basis of the electrostatic charge in the second region. The second effect addressed with the second segment can therefore comprise, for example, a change in a particle beam property in the first region on account of the electrostatic charge of the sample in the second region.In one example, by applying the second voltage to the second segment, an electrostatic charge in the second range may be in a predetermined range of values. It is therefore possible to set a value of the electrostatic charge for the second region in a targeted manner with the aid of the second segment on the basis of the determined electrostatic charge in the second region.Thus, by adjusting the second voltage at the second segment, a local charging effect of the sample in the second region may be addressed, such that processing and / or examination in the first region may be optimized.The mechanisms described herein for the first segment and the second segment may also be applied to elements having three or more segments. For example, a first set of two or more segments may be used to adjust the landing energy in the first region. In this case, different segment-specific voltages can also be applied to the segments of the first set in order to set the landing energy in the first range.Further, for example, a second set of two or more segments may be employed to suppress charge fields that may affect the first region. In this case, different segment-specific voltages can also be applied to the segments of the second set in order to minimize the effect of the charge fields on the particle beam present in the first region. For example, a plurality of locally distributed charge fields may be present on the sample, the disturbing effects of which can be minimized with the segment-specific voltages at the segments of the second set. For this purpose, it is also possible, for example, to determine the electrostatic charge on different regions of the sample from which the corresponding second set of segments is formed, which can address the charge fields present. Then, the segment specific voltages may be determined to minimize the disturbing effects of these charge fields.In one example, the element may be configured such that the two or more segments divide the top surface of the sample into corresponding two or more surface areas. A surface region can be exposed (substantially) to an electric field which originates from a segment which is assigned to this surface region. For example, the first segment (described herein) may confine the top surface of the sample to a first surface area. An electric field emanating from the first segment would therefore essentially act on this first surface region. The second segment (described herein) may confine the top surface of the sample to a second surface area. An electric field emanating from the second segment would therefore essentially act on this second surface region. Accordingly, this may apply to a third segment and a third surface area, a fourth segment and a fourth surface area, etc.By way of example, the two or more segments can also be understood as pixels of the element which divide the upper surface of the sample into corresponding surface pixels (the surface regions). For example, an electrostatic charge may be determined for one or more surface pixels. On the basis of this information, a voltage for the pixels of the element can be determined in order to optimize the processing and / or examination of the sample with the particle beam in a surface pixel (or a plurality of contiguous surface pixels).Accordingly, different voltages can be applied for different pixels of the element. This can result in various electric fields acting on the surface pixels of the sample. Each surface pixel can thus be assigned a corresponding electric field (with, for example, a maximum field strength). With this approach of the segmented element, local as well as global variations of the electrostatic charge of the sample can thus be addressed with a high degree of freedom in a technically reliable manner.In one example, the method of processing and / or examining an object for lithography may be performed. The sample can thus comprise, for example, an object for lithography.The object for lithography may comprise, for example, a mask for a lithographic method. For example, the object for lithography may include an object for optical lithography (e.g., the object may be configured to be exposed with exposure radiation during optical lithography). For example, the object may include an EUV mask for EUV lithography. However, it is also conceivable for the object to comprise a mask for any other optical lithographic method, for example for DUV lithography, UV lithography and / or X-ray lithography. For example, the object can comprise a transmissive and / or reflective mask for (optical) lithography. Thus, for example, the mask can be designed such that the exposure radiation during (optical) lithography transmits the mask or is reflected by the mask. It is also conceivable that the object for lithography does not necessarily include an object for optical lithography. Thus, the object for lithography can also be designed for non-optical lithography, e.g. also comprise a stamp for nanoimprint lithography.In an example, the object for lithography may also include a mask blank. Mask sheets are a well known source of mask material in the lithographic industry. The mask blank may, for example, not comprise any imaging structures, such as the mask itself, but the layer material thereof.In one example, however, the method can also be carried out for processing and / or examining any desired sample. The sample can also comprise, for example, a microchip, a wafer and / or a biological sample.In an example, the particle beam may comprise at least one of the following: an electron beam, an ion beam, a photon beam. For example, an electron beam can be used as a particle beam during the processing and / or examination of the sample. For example, an ion beam can be used as a particle beam during the processing and / or examination of the sample. For example, a photon beam can be used as a particle beam during the processing and / or examination of the sample.A second aspect relates to a computer program for executing a method of the first aspect.A third aspect relates to an apparatus for processing and / or examining a sample with a particle beam, comprising: means for determining an electrostatic charge of the sample; an element which is arranged in a vicinity of the sample when the sample is arranged in a sample position in the apparatus; means for applying a voltage to the element based at least in part on the determined electrostatic charge.In one example, the apparatus may further comprise: a memory comprising instructions for executing a method of the first aspect; a computer system which may control the means for determining and the means for applying, wherein when the computer system executes the instructions from the memory, the apparatus is caused to perform a method of the first aspect. The computer system can comprise, for example, a computer, a computing unit, a microprocessor, etc. For example, the computer system may be communicatively coupled to the components of the device such that a signal output of the computer system may cause a change in a component of the device.The device can be configured, for example, to run the method of the first aspect in an automated or semi-automated manner. The means for determining may comprise, for example, one or more components of the device, by means of which a determination of the electrostatic charge is made possible automatically (or semi-automatically) in the course of the method. For example, the electrostatic charge in the surface regions of the sample (also referred to as surface pixels) can be determined via the means for determining. The means for determining can comprise, for example, a configuration of the computer system of the device which triggers a determination of the electrostatic charge in the course of the method (for example after a defined time after the start of the method). This trigger can also be generated, for example, manually by an operator (e.g., via a corresponding user interface on the device). For example, the means for determining can also comprise a control unit which deflects and / or adapts the particle beam of the device in order to record positions of reference structures on the sample, for example, in order to determine the electrostatic charge. The computer system of the device can, for example, perform the arithmetic operations on the basis of the recorded positions of the reference structures for determining the electrostatic charge.The means for applying a voltage to the element based at least in part on the determined electrostatic charge may comprise one or more components of the device that may perform this functionality. Thus, the means for applying the voltage can comprise, for example, a control unit in which it is stored which voltage is to be applied. The means can thus automatically apply a corresponding voltage on the basis of the determined electrostatic charge. The control unit can be communicatively coupled to the means for determining, for example, such that the determined voltage can be stored in the control unit. The control unit can comprise, for example, a regulation and / or control which can regulate the application of the electrical voltage to the element. For example, the means for applying may also comprise a voltage source and / or a power circuit, which may enable the generation of the voltage. The control unit can be included in the computer system of the device, for example.The element may comprise (as described herein) an electrode which may be coupled to the means for applying. The means for applying can apply the generated voltage to the element, for example, via its control unit. For example, the device may be configured to position the element in a vicinity of the sample when the sample is in the sample position in the device. The sample position can correspond, for example, to a position of the sample in which the sample is processed and / or examined with the particle beam. The element can also be arranged statically in the device, for example, in such a way that positioning of the element is not always necessary (and the element is located in the environment of the sample without extensive readjustment when it is arranged in the sample position). The element can be configured, for example, in such a way that it also locates itself, for example, with the sample position. If, for example, the sample position changes, the positioning of the element can also correspondingly change, so that this can be in the vicinity of the sample without extensive readjustment.In one example, when arranging the sample in the sample position, the element can be arranged on an underside of the sample, which lies opposite an upper side of the sample, from which the particle beam is directed onto the sample during the processing and / or examination.For example, the element cannot be arranged on the side of the sample on which the particle beam source and / or an aperture of the particle beam is located. In this configuration, the element cannot be in the way of the particle beam when incident on the sample. A complex structure, which comprises e.g. a passage for the particle beam, can thus be avoided for the element. Complicated adjustments of the sample, of the element and / or corresponding positionings of the particle beam, so that the particle beam is directed onto the passage, can likewise be avoided, for example.In one example, the device may be configured such that upon application of the voltage, at least a portion of the bottom surface of the sample is in contact with the element.In one example, the member may include a support for holding the sample. The holder can comprise, for example, a sample stage and / or a chuck.In one example, the holder can comprise a base surface which is in contact with the underside of the sample when the sample is arranged in the sample position.In one example, the element may comprise two or more segments, wherein a first voltage may be applied to a first segment and a second voltage may be applied to a second segment of the element via the means for applying.It should be mentioned that the features mentioned herein (as well as examples) of the method (or of the computer program) can also be applied or can also apply in a corresponding manner to the mentioned device. For example, the features of the element (e.g. the holder) described with respect to the method can also apply to the element (e.g. the holder) which is comprised in the device of the third aspect. It should also be mentioned that the features mentioned herein (as well as examples) of the device can be applied or can apply in a corresponding manner to the method (or computer program) described herein.A fourth aspect relates to a holder for holding a sample in an apparatus for processing and / or examining the sample with a particle beam, the holder comprising: two or more segments; wherein the two or more segments are designed for coupling to a means for applying an electric voltage to the holder, wherein the two or more segments are designed for permanent contact with the sample during processing and / or examination.In one example, the bracket may include, for example, three or more segments. In one example, the bracket may include, for example, 10 or more segments. In one example, the bracket may include, for example, 100 or more segments. In one example, the bracket may include, for example, 1000 or more segments. In an example, the holder may be configured to hold a mask for (e.g., optical) lithography.It should be mentioned that the features mentioned herein (as well as examples) of the element (e.g. the holder) which are described with respect to the method and / or the apparatus can correspondingly also be applied or can also apply to the mentioned holder of the fourth aspect.4. Brief Description of the DrawingsIn the following detailed description, the following drawings are described: FIG. 1 A-C schematically shows the irradiation of an electrostatically non-charged lithographic mask with an electron beam, wherein the mask has a reference structure and a defect with four drift markings. FIG. 2 A-C schematically shows the irradiation of the mask of FIGS. 1 A-C, wherein the mask has a positive electrostatic charge. FIG. 3A-C schematically shows the irradiation of the mask of FIGS. 1A-C, wherein the mask has a negative electrostatic charge. FIG. 4 schematically shows an example of the aspects described herein, in which a sample is processed and / or examined with a particle beam, wherein a voltage is applied to an element in a vicinity of the sample on the basis of an electrostatic charge of the sample. FIG. 5 illustrates, by way of example, steps in a flow chart according to a method described herein. FIG. 6 schematically shows a further example of the aspects described herein, in which a sample is processed and / or examined with a particle beam, wherein the application of the voltage to the element comprises an application of segment-specific voltages to different segments of the element. FIG. 7 schematically shows, in a plan view, an example of a holder for holding a sample in a device according to the disclosure described herein.5. Detailed DescriptionExamples of the method and the apparatus described herein for processing and / or examining a sample are explained in more detail below using the example of lithographic masks and a modified scanning electron microscope. However, the method need not be limited to the reflective and transmissive photomasks described below. Rather, the method described herein can be used for any samples (e.g., for nanoimprinting lithography punches, wafers, ICs, MEMS, NEMS, and PICs, biological samples). Further, the apparatus described herein is not limited to the example described below. Instead of the modified scanning electron microscope discussed, it is also possible to use any scanning particle microscope which uses, for example, a focused ion beam and / or a focused photon beam as energy source.Presently preferred embodiments of the present invention are explained in more detail below with reference to the drawings.FIGS. 1A-C show an example lithographic mask 100 (hereafter briefly: mask 100) having a reference structure 130, a defect 150 and four reference elements 160 according to an example.FIG. 1A shows a section through the mask 100, the surface 105 of which carries a pattern 110 or a pattern 110. The surface 105 of the mask 100 is irradiated by an electron beam 120.For example, the electron beam for processing the mask 100 may be provided at a specific position of the surface 105. For example, an electron beam-induced reaction may be caused on the mask 100 with the electron beam and a gas provided. The electron beam induced reaction may include e.g. an electron beam induced deposition and / or an electron beam induced etching. The electron beam-induced reaction can be carried out, for example, as part of a repair of the masks (for example, in order to deposit or etch away missing or excess material, for example, of a pattern element of the mask).For example, the electron beam can also be provided for examining the mask 100 at a specific position of the surface 105. The electron beam can be scanned over the surface, for example, for an imaging of the mask 100. Electrons released as a result can be detected for image recording. The electron beam can thus be used for imaging purposes, as is known in a scanning electron microscope.FIG. 1B presents a schematic top view of a reference structure 130 of the mask 100. The example reference structure 130 of FIG. 1B is a square that is divided into nine sub-squares 140 by ridges 135. The reference structure 130 may be arranged distributed over the mask 100 at regular or irregular intervals. The reference structure 130 may be used to determine an electrostatic charge of the mask 100 (or generally of a sample 100). As a rule, both the positions of the reference structures 130 and their size are known by the manufacturer of the mask 100. If this is not the case, the positions and the size of the reference structures 130 can be determined with the aid of a mask inspection tool, for example.FIG. 1C shows a schematic top view of a defect 150 of the mask 100. The example defect 150 is an excess material defect or a dark defect 150. The method described herein may also be used for accurately processing and / or inspecting a missing material defect or a clear defect 150. The defect can be processed and / or examined as part of a (e.g. multi-step) repair process of the mask 100. Four reference elements 160 in the form of drift markings 160 are deposited around the defect 150 in FIG. 1C. The drift markings 160 can be deposited onto the mask 100 with the aid of an electron beam-induced deposition process with provision of at least one precursor gas in the form of a deposition gas around the defect 150. Reference may also be made to the publication WO2019238668A1, which relates to aspects of drift correction and also mentions, inter alia, the generation of drift marks and an exemplary drift correction. The drift markings 160 span a two-dimensional (2D) coordinate system in the example of FIG. 1C. Three reference elements 160 not arranged on a straight line are sufficient for spanning a 2D coordinate system. The drift markings 160 are predominantly scanned with the electron beam 120 from time to time during a repair process of the defect 150 in order to detect a drift of the defect 150 or of the drift markings 160 with respect to the reference positions of the drift markings 160. The change of the positions of the drift markings 160 with respect to their reference positions can also be used for determining an electrostatic charge of the mask 100 in addition to determining a relative drift between the electron beam 120 and the drift markings 160 of the mask 100 or of the defect 150.In order to raster the electron beam 120 over the defect 150 of the mask 100 during its repair, it may be advantageous to keep the landing energy of the electrons 125 on the defect 150 low in order to make the diameter of the local chemical reaction induced by the electron beam 120 as small as possible. The provision of the particle beam for processing as described herein can be effected, for example, with electron landing energies of 3 keV, 1 keV, 600 eV, preferably 400 eV and most preferably 300 eV or less. For imaging the drift markings 160, it may be advantageous, for example, to use electron landing energies which are also used for repair of a defect. The provision of the particle beam for examination described herein can be effected, for example, with electron landing energies in the range of 3 keV, 1 keV, 600 eV, preferably 400 eV and most preferably 300 eV or less. However, it can also be advantageous to implement the imaging of drift markings at electron landing energies different therefrom. The provision of the particle beam for examination described herein can be effected, for example, with electron landing energies in the range of greater than 600 eV, for example 3 keV.FIGS. 2A-C again repeat the representations of FIGS. 1A-C. In contrast to FIGS. 1A-C, however, the mask 100 in FIGS. 2A-C has a positive electrostatic charge 200. The electric field of the positive electrostatic charge 200 curves the electron beam 220 toward the surface 105 of the mask 100. For comparison, FIG. 2A additionally shows dotted lines of the electron beam 120 which would strike the surface 105 of the mask 100 if it were not positively electrostatically charged. FIG. 2B presents the reference structure 130 as it is imaged by the electron beam 220 due to the positive electrostatic sample charge 200 of the mask 100. In comparison with the reference structure 130 of FIG. 1B, the reference structure 130 of the positively electrostatically charged mask 100 appears reduced in size. FIG. 2C shows the mapping of the defect 150 and the four drift marks 160 that the electron beam 220 receives from these structural elements due to the positive electrostatic mask charge 200. The distance between the drift markings 160 of FIG. 2C appears to be reduced compared to that of FIG. 1C. Thus, the marked distance d1 between two reference marks in FIG. 2C is less than the distance do that exists between the same reference marks in FIG. 1C.FIGS. 3A-C show FIGS. 2A-C, wherein however, the mask 100 now has a negative electrostatic charge 300 instead of a positive electrostatic charge 200. The electric field of the negative sample charge 300 curves the trajectory of the electrons 125 of the electron beam 320 away from the surface 105 of the mask 100. For comparison, the trajectory of the electron beam 120 impinging on a non-electrostatically charged mask 100 is again reproduced in dotted lines. As illustrated in FIG. 3B, the deflection of the electron beam 320 caused by the negative electrostatic charge 300 increases the imaging of the reference structure 130 with respect to its image in FIG. 1B. The same applies to the imaging of the defect 150 and of the four drift markings 160 of FIG. 3C, again with respect to FIG. 1C. Thus, the marked distance d 2 between two reference markings in FIG. 3C is greater than the distance do present between the same reference markings in FIG. 1C.From the change in size of the reference structure 130, caused by an electrostatic charge 200, 300 of the mask 100 or generally of a sample 100, it is possible to determine both the size, i.e. the numerical value and the sign, of the electrostatic charge 200, 300 of the mask 100. As illustrated by FIGS. 3A, 3B and 3C, electrostatic sample charging 200, 300 may also be determined from measured displacements of the drift marks 160 with respect to their reference positions. This applies in turn to the magnitude and sign of an electrostatic sample charge 200, 300.FIG. 4 schematically shows an example of the aspects described herein, in which a sample is processed and / or examined with a particle beam, wherein a voltage is applied to an element in a vicinity of the sample on the basis of an electrostatic charge of the sample.In this example, the mask 100 includes a mask for EUV lithography (an EUV mask). The EUV mask 100 may comprise a substrate S. A multilayer stack B can be applied on the substrate S. The multilayer stack B can comprise a Bragg mirror, for example. The Bragg mirror can have a reflective effect with respect to the EUV radiation, for example, which is used in EUV lithography. A cover layer D can be attached to the multilayer stack B. The cover layer D can serve, for example, to protect the multilayer stack B. For example, one or more pattern elements P of the mask 100 can be attached to the cover layer D. The pattern elements P can be, for example, absorber structures which absorb the EUV radiation during EUV lithography. The pattern elements P can also be designed, for example, to absorb radiation and / or phase shift with respect to the EUV radiation during EUV lithography. The EUV mask can be electrically insulating, for example. For example, a layer of the EUV mask may have electrically insulating properties. A charge generated on the cover layer D or in a pattern element P could in such a case not flow off through the mask via the substrate, e.g. to a mask holder. For example, the substrate S may be electrically insulating. The substrate S may be adjoined by a coating layer C. The coating layer C can be e.g. electrically conductive. The coating layer C may define the bottom surface of the EUV mask 100, for example. The cover layer D with the pattern elements P can define the upper surface of the EUV mask 100, for example. Due to the electrical insulation of the EUV mask 100 (e.g. by the substrate S), a current cannot always flow from the upper surface to the lower surface. EUV masks therefore cannot always easily be electrostatically adapted when electrostatically charging. Thus, for example, a desired electrostatic charge of the EUV mask cannot always be easily adjusted technically.The electrostatic charge in the pattern elements P, the cover layer D and / or the multilayer stack B, for example, may be problematic, which may be caused, for example, by the electron beam E, which is directed onto the EUV mask 100 during processing and / or examination. For example, EUV masks 100 (or samples in general) can be processed and / or examined with a particle beam in an active region of the EUV mask 100, wherein the particle beam is directed onto the active region. By means of the particle beam (e.g. an electron beam), a charge can be introduced into a material of the EUV mask 100, for example (as described herein).As mentioned, a pattern element P may be defective, since mask errors (e.g. in the case of EUV masks) cannot always be avoided. For example, a material of the pattern element P may be missing, although material should be present there after the design of the mask 100. For example, a pattern element P may have excess material at locations where no material should be present after the mask 100 is designed. These errors may also cause corresponding errors in lithography (e.g., EUV lithography). The processing and / or examination of the EUV mask can therefore comprise, for example, a repair in which defective pattern elements P are repaired (for example by depositing and / or etching material). In this regard, reference is made in addition to the publication EP2702603A2, which relates to corresponding aspects of the repair of pattern elements. However, by means of the particle beam-based repair, it is possible to cause, for example, an (undesired) electrostatic charge of the mask.The EUV mask 100 can act like a capacitor, for example, as a result of the electrostatic charge. The pattern element P of the mask can comprise a metal, for example. Furthermore, the cover layer D can also comprise a metal. The multilayer stack B may also comprise a metal, e.g. one or more molybdenum layers. Charges introduced in these metallic regions can be stored, for example, in a delocalized manner (e.g., in contrast to local accumulation in non-conductive materials). Thus, for example, the upper (metallic) electrically conductive layers of the EUV mask 100 can act like a capacitor plate which has a specific charge globally.However, it should be noted that a local electrostatic charge may also be present in the metallic regions of the EUV mask 100. The local accumulation of charge may be caused, for example, by charge trapping at interfaces of the EUV mask 100. A charge may be trapped locally at these interfaces, for example, so that a local electric field is generated. The boundary surfaces can comprise, for example, adjoining layers, structure edges and / or surfaces.Local accumulations can also be caused, for example, by isolated structures on the EUV mask. Likewise, such insulated structures may be created by partially depositing non-conductive material during the examination and / or processing of the EUV mask 100 (e.g., during repair). As mentioned, EUV masks 100 can be processed and / or examined with a particle beam in an active region of the EUV mask 100. If electrically non-conductive material is present in this active region, it can be assumed, for example, that excess charge is predominantly introduced locally by the particle beam.In summary, an EUV mask can therefore charge up globally and / or locally electrostatically during the processing and / or examination with a particle beam.The method described herein can enable the effects of this electrostatic charge to be reliably overcome during the processing and / or examination of EUV masks.FIG. 4 illustrates an exemplary repair process of a pattern element P of the EUV mask 100. The repair process comprises processing and / or examining the EUV mask 100 with the electron beam E. This is provided by the electron beam source ES. The repair process may be performed, for example, in an electron beam device that also includes one or more components for controlling and / or focusing the electron beam.Furthermore, the electron beam device can comprise a holder H which is coupled to a voltage source U. The holder can comprise the element described herein, which is arranged in an environment of a sample (in this case the EUV mask 100). The holder H can also comprise a sample stage, for example, on which the EUV mask 100 is mounted. The sample stage can also be referred to as a "stage" (or "chuck"), for example. A voltage can be applied to the holder via the voltage source U. For this purpose, an electrode, for example, can be installed in the holder H, wherein the electrode is coupled to the voltage source U. For example, the holder H can also be electrically conductive and thus act as an electrode. By applying the voltage to the holder H via the voltage source U, an electric field can originate from the base surface of the holder H. In the example of FIG. 4, the base surface of the holder H is in contact with the coating layer C of the EUV mask 100. The electric field, starting from the holder H, can thus act globally on the EUV masks 100. The voltage of the voltage source U can be selected such that the electric field of the holder H at the point of incidence of the electron beam E on the EUV mask 100 is large enough to enter into an interaction with the electrons of the electron beam E.During the repair process with the electron beam E, the EUV mask 100 can charge electrostatically. The electric fields thus emanating from the EUV mask 100 can impair the electron beam E in an undesired manner. For example, the landing energy of the electron beam E may be caused to change in the course of the repair process. This can be addressed with the method described herein.During the method, a time-varying counterfield can be generated on the holder H in order to compensate for an electrostatic charge of the mask, which has been produced by bombardment with the electrons of the electron beam E during the repair of the EUV mask 100. For example, the landing energy of the electrons on the EUV mask 100 can be modulated with the holder H. The method described herein can make it possible for the landing energy of the electrons via the holder H to be dynamically corrected by the amount caused by electric fields of the EUV mask 100 during the processing and / or examination of the EUV mask 100.For this purpose, the electrostatic charge of the EUV mask 100 is first determined, e.g. on the basis of the analysis of structures on the EUV mask (as described herein). This information can be used to determine the voltage which must be applied to the holder H, so that the landing energy of the electrons again has the desired value.In FIG. 5, steps according to the method described herein are presented by way of example in a flow chart. First, in a first setting step S 1, the desired landing energy of the electrons can be set via a first voltage which is applied to the holder H via the voltage source U. If an electrostatic charge of the EUV mask 100 did not occur, this first voltage could be held statically across the method in this ideal case, since the landing energy would remain constant. However, this is usually not the case in reality due to the induced electrostatic charge of the EUV mask 100.In a next step, e.g. a repair step R, a repair of the EUV mask 100 can be effected with the electron beam E. This can comprise e.g. an electron beam-induced deposition and / or etching. In this case, the electron beam can also be guided over the EUV mask for imaging purposes. The repair may cause an electrostatic charge of the sample. During the repair, the electrostatic charge of the EUV mask 100 is determined in an analysis step A 1 according to the method described herein. For example, this is done via the analysis of scanning electron images of drift markings which are located on the EUV mask 100.In a next setting step S 2, a voltage is applied to the holder H based on the electrostatic charge determined (in the analysis step A 1). This step can also be referred to as a compensation step. The stress is selected in such a way that the holder H generates an electric counter-field which acts on the EUV mask 100. The electric counterfield can compensate for the electric field which originates from the EUV mask 100 due to the charges introduced during the repair. By means of the compensation, the landing energy of the electrons of the electron beam again corresponds to the setpoint value (set in the first step). A repair step R can then be carried out again, the repair being carried out with the desired landing energy by the applied voltage in the setting step S 2.The compensation by the holder can be effected dynamically during the repair. The steps can be repeated iteratively, for example, as shown in FIG. 5. Thus, during the repair, the electrostatic charge can be determined multiple times (analysis step A 1) and the compensation step (setting step S 2) can be carried out correspondingly, with a subsequent repair step R. Thus, in the method, a correction of the landing energy of the electrons can be carried out multiple times.It should be noted that the landing energy may be determined, for example, based on the settings of the electron beam device in combination with the determined electrostatic charge at the point of impact. For example, a set of one or more electron beam parameters may have been set via a setting of the electron beam device (e.g. a specific focusing, acceleration of the electrons, etc.). Starting from this set, a specific landing energy can be assumed. However, this can be reduced or increased by the electrostatic charge determined at the point of impingement. Based on the electrostatic charge, a corresponding amount can thus be subtracted from the landing energy or a corresponding amount can be added.FIG. 6 schematically shows a further example of the aspects described herein, in which a sample is processed and / or examined with a particle beam, wherein the application of the voltage to the element comprises an application of segment-specific voltages to different segments of the element. The sample of FIG. 6 comprises an EUV mask 100 as described for FIG. 4. Likewise, the EUV mask 100 is processed and / or examined with an electron beam E which originates from an electron beam source ES.However, in FIG. 6, a different holder H is present than in FIG. 4. the holder H of FIG. 6 comprises two or more segments, to each of which a segment-specific voltage can be applied, based on the determined electrostatic charge of the EUV mask 100. For example, a segment-specific voltage can be applied to a first segment 1 of the holder H via a first voltage source U 1. For example, a segment-specific voltage can be applied to a second segment 2 via a second voltage source U 2. For example, a segment-specific voltage can be applied to a third segment 3 via a third voltage source U 3. For example, a segment-specific voltage can be applied to a fourth segment 4 via a fourth voltage source U 3. The holder H can also comprise more than four segments, which are not shown for schematic illustration purposes, however.The holder of FIG. 6 may enable a space-dependent biasing of the EUV mask 100 for the method described herein. By means of the segment-specific voltages, segment-specific electric fields can be generated accordingly, which can act on different regions of the EUV mask 100. As described herein, the segments may also be referred to as pixels, wherein a pixel may influence a corresponding surface area (a corresponding surface pixel) of the EUV mask 100 by its electric field.Space-dependent biasing may be useful, for example, when the electrostatic charge is different at different locations of the EUV mask 100 (or more generally a sample). This may be the case, for example, in EUV masks, the conductive regions of which are not always continuous in specific regions of the mask surface. Different electrostatic charging at different locations can be present, for example, for the same reasons in DUV masks (for DUV lithography). Space-dependent biasing can thus be particularly useful, for example, for EUV masks and / or DUV masks.For example, the electron beam E can be directed onto a first region of the EUV mask 100 during the processing and / or examination. The corresponding position of the particle beam on the EUV mask can be specified, for example, as X 1, Y 1. The position X 1, Y 1 can also be a position of a surface region of the EUV mask 100, on which the electron beam arrives, for example. For this position (and / or the first region), an electrostatic charge can be determined. Subsequently, it can be determined to which segment of the holder which voltage must be applied in order to influence the electron beam in the first region, so that the desired landing energy is achieved. The corresponding application of the voltage can then take place, so that the desired landing energy is present. Thereby, the landing energy of the electrons at the position X1, Y1 can be locally set to a desired value.FIG. 7 schematically shows, in a plan view, another example of a segmented holder for holding a sample in a device according to the disclosure described herein. FIG. 7 shows an exemplary segmented holder H, which has a plurality of segments in the form of pixels, to each of which a pixel-specific voltage can be applied. A first pixel P 1 and a second pixel P 2 are highlighted, for example. As mentioned, the EUV mask may be divided into surface areas which may be referred to as surface pixels (e.g. a surface pixel at the position X 1, Y 1 of the EUV mask 100). If the EUV mask is fixed via the holder H, one or more pixels of the holder H can be assigned to a surface pixel of the EUV mask. During processing, for example, the electron beam E is directed onto a location within a first surface pixel at the position X 1, Y 1. The first surface pixel may also be understood as a first region of the sample (as described herein). This first surface pixel at the position X 1, Y 1 of the EUV mask can be assigned e.g. the first pixel P 1 of the holder H. In the context of the method, the electrostatic charge can be determined for the first surface pixel. Subsequently, a segment-specific voltage may be applied to the first pixel P 1 for desired adaptation of the landing energy of the electron beam in the first surface pixel at the position X 1, Y 1 (as described herein).However, due to the different local electrostatic charges of the EUV mask 100, an electric field can emanate from a second surface pixel of the EUV mask, which electric field interferes with the electron beam E impinging in the first surface pixel. The second surface pixel may also be understood as a second region of the sample (as described herein). This interference from the second surface pixel can be compensated for in a targeted manner via the segmented holder H. For example, an electrostatic charge can be determined for a second surface pixel at the position X 2, Y 2 of the EUV mask. It is then possible to determine which pixel of the holder H (e.g. a second pixel P 2) to which voltage has to be applied, so that the disturbing effect from the second surface pixel on the electron beam in the first surface pixel can be avoided. The corresponding application of the voltage to the pixel (e.g. the second pixel P 2) can then take place, such that the interference from the second surface pixel is reduced (or eliminated).In summary, disturbing electric fields resulting from local electrostatic charging in the vicinity of the position X 2, Y 2 of the EUV mask and proceeding to the spatial position X 1, Y 1 of the EUV mask can thus be avoided. At the same time, it can be possible for the electron beam to have the desired landing energy at the position X 1, Y 1. In the mentioned example, a segment-specific voltage would be applied to the first pixel P 1 for modulating the landing energy of the electron beam E incident on the first surface pixel (at the position X 1, Y 1) of the EUV mask. A segment-specific voltage would be applied to the second pixel P 2 in order to compensate for an interfering electric field which originates from the second surface pixel (at the position X 2, Y 2) of the EUV mask.Furthermore, a segment-specific voltage can also be applied to a plurality of segments (or pixels) of the holder H for adapting the landing energy of the electrons. Furthermore, segment-specific voltages for compensating one or more local electric interference fields emanating from the EUV mask 100 (e.g. from different surface pixels) can also be applied to a plurality of segments (or pixels) of the holder H.In general, multipole fields can be generated by the two or more segments of the holder H, which fields can be used in the methods described herein for implementing space-dependent biasing.Space-dependent biasing may also be repeated dynamically during processing and / or testing, as the local electrostatic charge may change dynamically.By way of example, the following steps may be listed in this regard, which may take place during the method during the processing and / or examination of the EUV mask with the electron beam E.In a first step, the charge can be determined at at least one position of the EUV mask 100 (e.g. X 1, Y 1; X 2, Y 2;...; Xn, Yn). This can be determined, for example, on the basis of reference structures (for example by determining scale factors). For example, one or more repair steps may already have been carried out with the electron beam E, so that an electrostatic charge is present.In a second step, it is possible to determine which segment-specific voltages (e.g. U 1, U 2,..., UN) have to be applied to the two or more segments of the holder in order to generate the local electric fields caused by the electrostatic charge at the determined positions (e.g. X 1, Y 1;... Xn, Yn) and / or to cause a desired landing energy at a specific position of the EUV mask 100. The determination of the segment-specific voltages can be based, for example, on a calculation of a model. For example, calculation can be carried out via finite element methods for this purpose, wherein the model can comprise a simulation model of the holder H (and e.g. also of a sample). By means of the calculation it can be derived, for example, in which frame the segment-specific voltages must be applied in order to achieve a desired effect. The simulation may be predetermined, for example, and does not necessarily need to be performed at the time of repair.In a third step, the previously determined segment-specific voltages can be applied to the segments of the holder H, so that the local electric fields are compensated for and / or the desired landing energy is present. This step can also be referred to as a compensation step, for example.The first, second and third steps may be repeated multiple times in the method in order to take account of a change in the electrostatic charge during the method. Naturally, further sequences can be carried out before, after or between these steps within the scope of the method (e.g. with the electron beam E).In summary, for a holder having two or more segments, the application of the segment-specific voltages can also be carried out dynamically based on repeated determinations of the present (e.g. local or global) electrostatic charges of the EUV mask 100.In one example, the method described herein can be carried out with the electron beam in such a way that it can be ensured during the processing and / or examination of the mask with the electron beam that a minimum repair size of the mask is better than 12 nm. For example, in the case of a pattern element A, excess material can protrude. Thus, for example, excess material can protrude up to a specific length with respect to a desired edge of the pattern element A. For repair, this excess material would have to be removed as far as the desired edge in order to repair the pattern element. The minimum repair variable can comprise, for example, the length of the excess material from the desired edge, from which it can be ensured that the removal of this excess material leads to a correction of the pattern element (or of the mask) during the repair. By the method described herein taking into account the electrostatic charge of the mask, it is also possible, for example, to remove very delicate overhangs which project from the pattern element, for example, between 5 nm and 12 nm, with the electron beam, with the result that the mask is repaired.In one example, the method described herein can be carried out with the electron beam in such a way that it can be ensured during the processing of the mask with the electron beam that a minimum repair size of the mask is better than 15 nm, preferably better than 12 nm or even better than 11 nm. This can be the case, for example, with silicon nitride-based masks. In one example, the method described herein can be carried out with the electron beam in such a way that it can be ensured during the processing of the mask with the electron beam that a minimum repair size of the mask is better than 10 nm. This can be the case, for example, in tantalum nitride-based masks.

Claims

A method for processing and / or examining a sample (100) with a particle beam (E), comprising the steps of: determining an electrostatic charge of the sample (100); applying a voltage to an element (H) in an environment of the sample based at least in part on the determined electrostatic charge; wherein the element (H) comprises two or more segments; and wherein applying the voltage comprises: applying a first voltage to a first segment (1, P1) of the element (H); applying a second voltage to a second segment (2, P2) of the element (H).The method according to claim 1, wherein the application of the voltage causes an electric field at a point of impingement of the particle beam (E) on the sample (100).Method according to either of Claims 1 and 2, wherein the voltage is applied in such a way that an influencing of a landing energy of particles of the particle beam on the sample is caused.Method according to claim 3, wherein the voltage is applied in such a way that the landing energy lies in a first predetermined value range.Method according to one of Claims 1-4, wherein the voltage is applied in such a way that the electrostatic charge of the sample is at least partially compensated.Method according to Claim 5, wherein the electrostatic charge is in a second predetermined value range as a result of the application of the voltage.The method of any of claims 1-6, wherein the steps of claim 1 are repeated at least once.Method according to one of Claims 1-7, wherein the element is arranged on an underside of the sample which lies opposite an upper side of the sample from which the particle beam is directed onto the sample during the processing and / or examination.The method of claim 8, wherein upon application of the voltage, at least a portion of the sample is in contact with the element.The method of claim 8 or 9, wherein the member comprises a holder for holding the sample.The method of claim 10, wherein the holder comprises a base surface that is in contact with the sample during the method.The method according to any one of claims 1-11, wherein the application of the first and second voltages for influencing the processing and / or examination of the sample takes place in a first region of the sample.The method of claim 12, wherein applying the first voltage causes an influence on the landing energy of particles of the particle beam in the first region.The method of any of claims 12 or 13, wherein determining the electrostatic charge comprises: determining an electrostatic charge in a second region different from the first region, wherein applying the second voltage is based at least in part on the electrostatic charge determined in the second region.The method of claim 14, wherein applying the second voltage suppresses an electric field emanating from the second region.Method according to one of claims 1 - 15, wherein the method is carried out for processing and / or examining an object for lithography.Computer program for executing a method according to one of claims 1 - 16.An apparatus for processing and / or examining a sample (100) with a particle beam (E) comprising: means for determining an electrostatic charge of the sample; an element (H) arranged in a vicinity of the sample when the sample is arranged in a sample position in the apparatus; means for applying a voltage to the element (H) based at least in part on the determined electrostatic charge; wherein the element (H) comprises two or more segments; wherein a first voltage can be applied to a first segment (1, P1) and a second voltage can be applied to a second segment (2, P2) of the element via the means for applying.The device according to claim 18, wherein when the sample (100) is arranged in the sample position, the element (H) is arranged on an underside of the sample (100), which lies opposite an upper side of the sample (100), from which the particle beam (E) is directed onto the sample (100) during the processing and / or examination.The device of claim 19, wherein the device is configured such that upon application of the voltage, at least a portion of the bottom surface of the sample (100) is in contact with the element (H).The apparatus of any one of claims 18-20, wherein the member comprises a support for holding the sample.The apparatus of claim 21, wherein the holder (H) comprises a base surface which is in contact with the underside of the sample (100) when the sample is placed in the sample position.

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