Method and apparatus for contactless setting of sample electrostatic charge

Abstract

The present invention relates to a method (1400) and a device (1300) for setting an electrostatic charge (200, 300) of a sample (100, 600, 1000, 132). The method (1400) comprises the steps of: (a) adjusting (1420) at least one parameter of at least one particle beam (120, 420, 720, 131) such that, on average, each particle (125) of the at least one particle beam (120, 420, 720, 131) incident on the sample (100, 600, 1000, 131) releases a predefined average number of electrons from the sample (100, 600, 1000, 131); and (b) irradiating (1430) the sample (100, 600, 1000, 131) with at least one conditioned particle beam (720) to set the electrostatic charge (200, 300) of the sample (100, 600, 1000, 131).

Description

[0001] This patent application claims priority to German patent application No. DE 10 2023 200 591.3, entitled “Verfahren und Vorrichtung zum kontaktlosen Einstellen einerelektrostatischen Aufladung einer Probe” [Method and device for the contactless setting of an electrostatic charge of a sample], filed with the German Patent and Trademark Office on January 25, 2023. This German patent application is incorporated herein by reference in its entirety. Technical Field

[0002] The present invention relates to a method and a device for contact-free setting of the electrostatic charge of a sample, in particular a photolithography mask. Background Art

[0003] As integration density in microelectronics continues to increase, photolithography masks must image ever-smaller structural elements into the photoresist layer of the wafer. To meet these requirements, exposure wavelengths are shifting to ever-shorter wavelengths. Currently, argon fluoride (ArF) excimer lasers, which emit at a wavelength of 193 nm, are primarily used for exposure. This intensive process is accomplished using light sources emitting in the extreme ultraviolet (EUV) wavelength range (10 nm to 15 nm) and corresponding EUV masks. The resolution capability of the wafer exposure process has been increased through the simultaneous development of multiple variants of conventional photolithography masks. Examples include phase or phase-shift masks and masks for multiple exposures.

[0004] Due to the ever-decreasing size of structural elements, photolithography masks, in particular optical photolithography masks, cannot always be produced defect-free. Since the production of masks is expensive, defective masks are repaired whenever possible. Two important groups of defects in optical photolithography masks are firstly dark defects. These are locations where adsorbates or phase-shifting material are present, but should be free of such material. These defects are repaired by removing excess material, preferably by means of local etching processes. Secondly, there are so-called obvious defects. These are defects on the mask which, during optical exposure in a wafer stepper or wafer scanner, have a higher light transmittance than an equivalent, defect-free reference location. In the mask repair process, these defects can be eliminated by depositing a material with suitable optical properties. Ideally, the optical properties of the material used for the repair should correspond to those of the adsorbates or phase-shifting material.

[0005] Defects can be further categorized as developable and non-developable defects. During wafer exposure, a mask with developable defects or developable mask defects produces a pattern that does not meet all design specifications. In contrast, a mask with one or more non-developable defects produces a pattern on the wafer that meets all design specifications during wafer exposure. When defects are mentioned below, these defects are understood to refer only to developable or developable defects.

[0006] US 2002 / 0070340 A1 describes an electron microscope (low-energy electron microscope, LEEM) using two beams containing low-energy electrons. The low-energy beam releases fewer than one electron from the sample per primary beam electron incident on the sample and compensates for the yield of the higher-energy primary beam (which is > 1), preventing electrostatic charging of the sample.

[0007] The applicant has developed and manufactures a device for analyzing, for example, the VEGAQRS (Proven Detection and Analysis System) under the trade name PROVE ® 、AIMS TM , or WLCD. In addition, the applicant develops and sells measurement equipment for optical lithography masks, for example under the trade name MeRiT ® , RegC ® , or Fortune ® A known optical lithography mask repair device is provided.

[0008] Repair is typically performed using a particle beam (e.g., containing electrons, ions, atoms, molecules, and / or high-energy photons) with defined beam parameters. Together with a precursor gas to which the sample (e.g., a mask) is exposed, the particle beam stimulates a localized chemical reaction on the sample (e.g., a mask) under defined process parameters. This results in localized material deposition or removal from the sample.

[0009] The use of particle beams to inspect and / or process samples is often associated with the introduction and / or generation of electrical charge, typically electrons, in the sample. For example, charge can accumulate through mechanical processes and / or during processing and / or imaging of a sample (such as a semiconductor substrate) using charged particles and / or EUV photons. This often results in electrical or electrostatic charging of the sample. This charging can cause distortion in the imaging of the site to be analyzed (such as a defect), thereby degrading the image quality of the defective site and / or the process of processing the defect in the sample.

[0010] In conductive samples, the locally generated charge is distributed within the sample, which is thus electrostatically charged as a whole. Grounding the sample makes it possible to largely prevent electrostatic charging. In non-conductive samples, the local generation of charge leads to local electrostatic charging of the sample and the associated electric field. As described in EP 1587128, the effect of electrostatic charging on the charged particle beam can be significantly reduced by a metal diaphragm mounted at a small distance above the sample. However, this diaphragm may adversely affect the imaging and / or processing of the sample and cannot be used in some applications.

[0011] Flood guns or plasmas are known as irradiation guns for compensating for electrostatic charging. However, when used, the site to be analyzed or treated is usually directly irradiated over a large area. In the case of mask repair, there is a risk of unwanted interactions with the particle beam-induced processes. Furthermore, the large-area application of plasma charged particles can lead to chemical changes in the sample composition. Furthermore, in both cases, it is not possible to set a specific charge state for the sample. Furthermore, the electrostatic charge cannot always be determined in advance with the necessary accuracy during the analysis and / or treatment process. This complicates computer-assisted correction of beam deflections caused by charge accumulation in the sample.

[0012] US Patent No. 6,734,443 B2 describes a method for removing contaminants and controlling localized electrostatic discharge during the manufacture of semiconductor components, such as optical lithography masks. To this end, the mask and pellicle are placed in a chamber filled with an inert gas, and the individual components are irradiated with ultraviolet (UV) radiation prior to assembly. For EUV masks, this radiation is in the wavelength range of 1 nm to 157 nm, while for masks with an actinic wavelength of 157 nm, it is in the range of 157 nm to 206 nm.

[0013] In order to minimize the effects of drift of the particle beam relative to a non-conductive sample (such as a transmissive mask), one or more reference structures (drift markers) (as explained in US 2012 / 0273458 A1) are often placed near the defective sample site during the processing of the site to be analyzed and / or during data acquisition therefrom, and are imaged regularly during the imaging and / or processing process. The measured deviation is used to correct the beam positioning (DC stands for drift correction). Generally, the particle dose used to repair sample defects is different from the particle dose used to analyze the reference structure and / or the defective sample structure. If the site to be repaired and the reference structure are not electrically connected to each other, different amounts of charge are generated at the different sites, so the beam deflection detected at the reference site does not match the beam deflection at the processing site.

[0014] DE 102021210019.8 from the applicant alleviates this problem by depositing a conductive layer or protective layer around the defective site, which is electrically connected to a drift marker or reference structure for correcting the drift between the particle beam and the defective site. The conductive protective layer acts as a capacitor. However, this causes the undesirable effect of increasing the amount of deposited charge over time. This occurs in particular in masks without a continuous conductive surface structure, such as masks for ultraviolet (UV) and vacuum ultraviolet (VUV) wavelength ranges. If the electric field associated with the electrostatic charge exceeds a predefined limit value, the force acting on the particle beam becomes so large that the resulting effect (e.g., beam deflection or significant change in the field of view) can no longer be tolerated, because processing and / or analyzing the sample can no longer be performed within the predefined specifications of the device in question.

[0015] On the other hand, EUV masks (i.e., masks for use in the extreme ultraviolet (EUV) wavelength range) contain flat areas of conductive material, such as metal adsorbent elements on a metal capping layer and Bragg mirrors containing molybdenum (Mo) layers. In these connected metal areas, introduced charges can be stored in a delocalized manner, as opposed to localized accumulation in non-conductive materials (such as the quartz substrate of a transmissive mask). This allows the EUV mask to act as a capacitor. The electric fields generated by these charges can interfere with imaging and / or processing of the EUV mask using a charged particle beam. This aspect is described in application DE 102019200696 A1 from the present applicant.

[0016] Direct electrical contacting of the EUV mask (i.e. its grounding) is often problematic because it can damage the mask. Furthermore, in the boundary areas, the structures on the EUV mask are often interrupted by so-called black borders, which means that it is not known where the electrical contact is to be made.

[0017] The present invention is therefore based on the problem of improving the known methods for imaging and / or processing samples, in particular samples in the form of photolithography masks having defects. Summary of the Invention

[0018] This problem is at least partially addressed by various aspects of the present invention.

[0019] According to one aspect, a method for setting the electrostatic charge of a sample comprises: (a) adjusting at least one parameter of at least one particle beam so that, on average, each particle of the at least one particle beam incident on the sample releases a predefined average number of electrons from the sample; (b) irradiating the sample at at least one first location with at least one adjusted particle beam to set the electrostatic charge of the sample; (c) readjusting at least one parameter of the at least one particle beam and / or adjusting at least one other particle beam to analyze and / or process at least one second location of the sample; and (d) irradiating at least one second location of the sample with the readjusted at least one particle beam and / or the adjusted at least one other particle beam, wherein the at least one first location and the at least one second location are at a predefined distance and are conductively connected to each other.

[0020] Setting the electrostatic charge at two different locations or positions of the sample and processing the sample avoids the complex superposition of two particle beams that differ in at least one parameter on the sample. In addition, the spatial separation between setting the charge and processing opens up new process control possibilities. In the case of simultaneous irradiation using a first particle beam to set the charge distribution and a second particle beam to process a defective sample, one or more parameters of the first and second particle beams may change without affecting the point at which the particle beams impinge on the sample. Setting the electrostatic charge of the sample has virtually no effect on its analysis and / or processing. In addition, the electrostatic charge can be set by adjusting the particle beam so that the adjusted particle beam does not substantially damage the sample to be processed.

[0021] Furthermore, the above-mentioned method according to the present invention can be performed using a single particle beam by setting the electrostatic charge of a sample and continuously analyzing and / or processing it. Particularly advantageously, the method according to the present invention can be used to analyze and / or process conductive samples. In this case, a spatial separation between setting the electrostatic charge and analyzing and / or processing can be achieved without the need for additional process steps.

[0022] Steps b. and d. of the above method according to the present invention may be performed simultaneously.

[0023] The two particle beams do not have to overlap. This allows the described method to be easily implemented. In addition, at least one parameter of the first particle beam can be set independently of at least one parameter of the second particle beam.

[0024] Steps b. and d. of the above method according to the present invention may be performed sequentially.

[0025] Thus, the spatial or local distance between the points at which the electrostatic charge of the conductive sample is set and the particle beam for analyzing and / or treating the sample is incident, thus additionally allowing greater flexibility in the temporal dimension. This makes it possible to use an apparatus with a single particle beam to analyze or treat samples that simultaneously have a controlled electrostatic charge. This makes it possible to significantly reduce the complexity of the apparatus for carrying out the method according to the invention.

[0026] The processing particle beam can have a lower particle kinetic energy than the analysis particle beam. The electrostatic charge of the sample (to be processed) can be set independently, for both the processing particle beam and the analysis particle beam.

[0027] The analyzing particle beam can image the sample, in particular the second site, by scanning the sample.The second site or the site to be processed may comprise a defective site or defect in the sample.

[0028] The at least one particle beam may irradiate at least one first site with a first modification, irradiate at least one second site with a second modification for processing purposes, and irradiate at least one second site with a third modification for analysis purposes.

[0029] This means that the particle beam setting the electrostatic charge of the sample surface can be adjusted such that processing with the second adjustment and analysis with the third adjustment of the particle beam are performed without exceeding a predefined electrostatic potential.

[0030] In addition, at least one particle beam can also irradiate at least one first site with a first adjustment and at least one second site with a second adjustment to analyze them, and at least one particle beam can irradiate at least one first site with a third adjustment and at least one second site with a fourth adjustment to process them.

[0031] At least one particle beam may irradiate at least one first site with a first adjustment and at least one other particle beam may irradiate at least one second site with a first adjustment to process it, or at least one particle beam may irradiate at least one first site with a second adjustment and at least one other particle beam may irradiate at least one second site with a second adjustment to analyze it.

[0032] The predefined distance can be selected so that the irradiation of at least one first location using at least one particle beam at the predefined distance does not substantially affect the irradiation of at least one second location using at least one particle beam or at least one other particle beam to analyze and / or process at least one second location of the sample.

[0033] This means that the irradiation of the at least one site with the modified particle beam has virtually no effect on the execution of an adjacent localized chemical reaction for treating a defective site or for repairing a defect in the sample by the at least one particle beam and / or the at least one other particle beam. Conversely, the adjacent execution of the localized chemical reaction does not affect the setting of a predefined electrostatic charge of the site to be treated by irradiating the at least one site with the modified particle beam.

[0034] The predefined distance may comprise a minimum distance that may not be dropped below.

[0035] The predefined distance between the at least one first location and the at least one second location may comprise at least a length or a width of a scanning area of ​​the at least one particle beam.

[0036] If the length and width of the scanning area have different values, the predefined distance refers to the size with the smaller value.

[0037] The scanning area of ​​the particle beam can cover 、Optimal , more preferably , and most preferably The predefined distance may exceed the length or width of the scanning area by 2 times, preferably by 10 times, more preferably by 100 times, and most preferably by 500 times.

[0038] Irradiating the at least one second site to treat the at least one second site may include providing at least one precursor gas at the at least one second site. The at least one second site may contain a defect in the sample to be treated. The at least one precursor gas may include at least two elements from the group consisting of a deposition gas, an etching gas, or an additive gas. Treating the at least one second site may include inducing a localized chemical reaction of the at least one precursor gas using a particle beam and / or other particle beams.

[0039] At at least one first site, the concentration of at least one precursor gas may be less than 50%, preferably less than 10%, more preferably less than 1%, and most preferably less than 0.1% of the maximum concentration at at least one second site to be treated.

[0040] At at least one first site, the occupancy density of at least one precursor gas may be less than 50%, preferably less than 10%, more preferably less than 1%, and most preferably less than 0.1% of the maximum occupancy density at the second site to be treated. The occupancy density describes the number of precursor gas molecules adsorbed per unit area (e.g., per cm2). 2 quantity).

[0041] The predefined distance between the at least one first site and the at least one second site may be at least 20 μm, preferably at least 200 μm, more preferably at least 2 mm, and most preferably at least 10 mm.

[0042] The method according to the present invention may further comprise depositing a conductive sacrificial layer on at least one second site of the sample using at least one particle beam and at least one precursor gas. The deposition of the conductive sacrificial layer may occur around at least a portion of the site to be treated, or around a defect to be treated.

[0043] The deposition of a conductive sacrificial layer around at least a portion of the site to be treated makes it possible to protect the sample in the region of the defective site during its treatment and to set an electrostatic charge in the region of a second site to be treated of the electrically insulating sample at a predefined distance from the site to be treated.

[0044] The method according to the present invention may further comprise: depositing at least one drift mark adjacent to the site to be processed by at least one particle beam and at least one precursor gas. The at least one drift mark may be deposited on the conductive sacrificial layer.

[0045] Furthermore, the method according to the invention may comprise determining a reference position of the at least one drift marker before starting the treatment of the at least one defective site.

[0046] The method according to the present invention may further include: interrupting the irradiation of at least one particle beam or at least one other particle beam in order to treat at least one second site; determining the position of at least one drift mark; determining the deviation of the determined position of at least one drift mark from a reference position; correcting the determined deviation of the position of at least one particle beam or at least one other particle beam incident on at least one second site; and continuing the irradiation with the corrected particle beam to treat at least one second site.

[0047] The interruption of the treatment and the correction of the drift of the at least one particle beam can be repeated at regular or irregular time intervals. The iterative treatment of the second site to be treated can continue until the remaining defect residue of the site to be treated is less than a predefined critical value.

[0048] According to a second aspect, a method for setting the electrostatic charge of a sample comprises: (a) adjusting at least one parameter of at least one particle beam so that, on average, each particle of the at least one particle beam incident on the sample releases a predefined average number of electrons from the sample; and (b) irradiating the sample with the at least one adjusted particle beam to set the electrostatic charge of the sample.

[0049] The method according to the present invention does not require any direct electrical contact with the sample, and thus avoids associated costs, and in particular associated risks. In addition, the described method not only allows the controlled discharge of the electrostatic charge of the sample, but also allows the controlled setting of the defined electrostatic charge of the sample surface. In addition, setting, improving, or adjusting the electrostatic charge does not affect the analysis performed on the sample, such as its imaging and / or processing. In addition, the accumulated charge can be removed in a controlled manner from a non-conductive sample (such as, for example, a transmission mask, etc.). In addition, the described method has the following advantages: the particle beam that has been used for analyzing and / or processing the sample may also be used to set a defined electrostatic charge. In addition, the particle beam may also be used to determine the size and mathematical sign of the electrostatic charge. Therefore, the cost of the equipment used to perform the method according to the present invention is low.

[0050] Finally, contactless setting of electrostatic charge can be advantageously used to repair photolithography masks. Thus, the mask's electrostatic charge, generated by the inspection step, can be set to a desired potential or level before the defect repair process is performed. After the repair process has been performed, the mask's electrostatic charge can be determined and set to a level that does not affect subsequent inspection processes used to verify the success of the repair.

[0051] The electrostatic charge of the sample can be set in a contactless manner.

[0052] Irradiating the sample may comprise at least one of focusing at least one particle beam with a first adjustment on the sample and directing at least one flat extension of the particle beam with a second adjustment onto the sample.

[0053] The sample can be analyzed and / or processed using a focused particle beam. This is also known in the professional field as a "writing gun". The adjustment of at least one particle beam when analyzing the sample may be different from the adjustment of at least one particle beam when processing the sample. Therefore, the analysis and processing of the sample may result in different electrostatic charges. The alignment of the flat extended adjusted particle beam corresponds to the effect of a flood gun on the site to be analyzed or processed. This makes it possible to set the electrostatic charge of the area under examination or the processed area of ​​the sample to a desired potential level.

[0054] Adjustment of at least one parameter of at least one particle beam and / or at least one other particle beam may comprise changing at least one parameter from the following group: the impact energy of particles of at least one particle beam and / or at least one other particle beam incident on the sample, the wavelength of particles of at least one particle beam incident on the sample, the flux density of particles of at least one particle beam and / or at least one other particle beam incident on the sample, and the irradiation time of particles of at least one particle beam and / or at least one other particle beam incident on the sample.

[0055] The flux density, irradiation area and irradiation time of the particles of at least one particle beam and / or at least one other particle beam incident on the sample determine the irradiation dose applied by the at least one particle beam. The irradiation dose can be applied to the site of the sample by a single irradiation operation in a time period determined by the irradiation dose. The treatment dose can also be applied with a partial dose by periodic irradiation. In order to apply a predefined irradiation dose in the area of ​​the sample, the at least one particle beam can be scanned thereon. The beam spot of the at least one particle beam can be adapted to the area to be irradiated of the sample.

[0056] A particle beam with sufficient energy to release electrons from a sample can cause electrostatic charging of the sample, particularly a non-conductive sample or a conductive, ungrounded sample. If the beam incident on the sample (hereinafter also referred to as the primary beam) contains electrically neutral particles (such as photons and / or atoms), the electrically insulating sample will always be electrostatically positive. Since the primary beam should not have a destructive effect on the sample during inspection and / or processing of the sample, i.e., a sputtering effect is not desired, the photons and / or atoms of the primary beam primarily generate free electrons in the sample. Some of these electrons may leave the sample as secondary particles. In addition to photons of various wavelengths, secondary particles include, in particular, secondary electrons (SE) and / or backscattered electrons (BSE), which are used to detect the electrostatic sample charge. The SE and BSE that leave the sample result in an excess of positive charge in the sample irradiated by the electrically neutral primary beam. This can be reduced or compensated, for example, by irradiation with an electron beam whose electrons have a corresponding impact energy.

[0057] Primary beams containing neutral or positively charged particles produce SE, not BSE. Generally, BSE only occurs when the primary beam contains electrons. This should be taken into account when discussing SE and BSE emission via particle beams below.

[0058] When the sample is irradiated with a primary beam containing (positively charged) ions, the charge balance is also positive. Because the ions in the primary beam introduce positive charge into the sample, and the BSE and SE additionally remove negative charge from the sample, the sample becomes electrostatically positive. The excess positive charge can be set, for example, by irradiating with electrons having appropriately adjusted impact energy.

[0059] If negatively charged particles (such as electrons) are used in the primary beam, the charge balance of the sample may turn out to be positive, negative, or neutral, depending on whether, on average, for each negatively charged particle in the primary beam incident on the sample, more or less than one secondary particle (the sum of BSE and SE) is able to leave the sample.

[0060] When irradiating with a massive particle beam, the charge balance of the sample depends on the particle impact energy on the sample. At very low impact energies, massive particles in the primary beam release, on average, less than one secondary particle (BSE and SE) per incident primary particle, resulting in a low electrostatic charge on the sample, the sign of which is determined by the charge of the particles in the primary beam. As the impact energy increases, the number of SEs and BSEs that can leave the sample increases, and thus its electrostatic charge also increases. As previously explained, the sign of the electrostatic sample charge can be reversed depending on the charge of the particles in the primary beam.

[0061] In the case of electrons, which are often used as the primary beam, the charge balance is negative at low impact energies, and the sample is negatively charged. Within the average impact energy range, the electrons of the primary beam generate, on average, more than one SE and BSE in total, and the sample is positively charged. At high impact energies of the electrons of the primary beam, the rate of SE and BSE generation decreases again, and the charge introduced into the sample by the electrons of the primary beam dominates the charge balance.

[0062] At least one parameter of at least one particle beam and / or at least one other particle beam may depend on the material composition of the irradiation area of ​​the sample and / or the surface profile of the irradiation area of ​​the sample. On the one hand, the atomic number of the material or material composition of the sample to be analyzed or processed affects the SE and / or BSE generation rate of the primary beam. On the other hand, edges and / or spikes on the surface particularly locally increase the SE generation rate of the primary beam. The SE yield of a sample or solid is determined by its electrical structure, the energy positioning of the valence band and conduction band, the Fermi level, and the discharge work that the SE must overcome on the surface.

[0063] If photons are used as a primary beam, there is a critical wavelength at which a photon can release electrons from its bond in the sample. As the wavelength decreases, that is, as the energy increases, the electron release rate (i.e., the SE generation rate or its yield coefficient) increases. If the photons have a wavelength shorter than the critical wavelength, the SE generation rate also depends on the flux density of the primary beam incident on the sample. This means that the greater the beam intensity of the photon beam (above the critical energy value), the larger the SE beam generated by the sample.

[0064] Adjusting at least one parameter of at least one particle beam may comprise at least one element from the following group: setting a fixed value; setting a range of values ​​through which the at least one parameter passes at least once during irradiation of the sample; and a range of offset values.

[0065] At least one parameter can pass through a range of values ​​linearly or nonlinearly. In addition, at least one parameter of at least one particle beam can oscillate within a range of values. The amplitude of the oscillation may be constant or may vary within a predefined range of values.

[0066] Setting a value range for at least one parameter allows for experimental determination of the optimal value of the at least one parameter. This procedure can be advantageous if the material composition and / or profile of the sample is unknown or not known in detail. Furthermore, this procedure can be advantageous if the effects of the particle beam on the sample are not fully known.

[0067] Adjusting the at least one parameter may further comprise at least one of determining a current intensity and / or a flux density of the at least one particle beam and determining an irradiation time of the sample with the at least one particle beam and / or at least one other particle beam.

[0068] In addition to the impact energy, the current intensity or flux density of at least one particle beam determines the charge q(t) generated per unit time in the sample by the particle beam. The charge accumulated in the sample during the irradiation time t2-t1 is given by the electrostatic charge .for , balance value Build up for accumulated charge. If the sample is an electrical insulator, the charge accumulates locally. This can lead to large local electrostatic charges, accompanied by high electric field strengths.

[0069] Irradiation with a first adjustment of at least one parameter of at least one particle beam may cause the sample to be electrostatically positive / negatively charged, while irradiation with a second adjustment of at least one parameter of at least one particle beam may cause the sample to be electrostatically negative / positively charged.

[0070] For example, a sample can be analyzed or imaged using a higher impact energy of the primary beam to improve the lateral spatial resolution of the particle beam used. If the primary beam uses electrons and the sample to be analyzed includes a mask, a kinetic energy > 2 keV, such as 2 keV to 5 keV, 2 keV to 4 keV, 2.5 keV to 3.5 keV, or approximately 3 keV (electron impact energy) can be used for the imaging process. To optimize the lateral spatial resolution of localized particle beam-induced chemical reactions, electron impact energies in the range of 20 eV to 2500 eV, 40 eV to 2000 eV, 70 eV to 1500 eV, 100 eV to 1100 eV, 150 eV to 800 eV, or 200 eV to 600 eV can be used for the repair process.

[0071] Analysis and / or processing of a sample using at least one particle beam may result in different electrostatic charges because the two processes may use different impact energies of particles of the primary beam. The electrostatic charge of the sample may be set before or after the sample is imaged using adjustment of at least one parameter of the at least one particle beam that is different from adjustment of at least one parameter of the at least one particle beam for setting the electrostatic charge after the processing process has been performed.

[0072] Irradiation of the sample with the second adjustment of at least one parameter of the at least one particle beam may substantially compensate for electrostatic charging of the sample generated by irradiation of the sample with the first adjustment of at least one parameter of the at least one particle beam.

[0073] As a special case of setting the electrostatic charge, the second adjustment of the at least one particle beam can be tuned such that the electrostatic charge of the sample caused by the first adjustment of the at least one parameter is compensated by irradiating the sample with the second adjustment of the at least one parameter.

[0074] Here, as elsewhere in this application, the word "substantially" refers to an indication of a measured quantity that is within customary error using metrology according to the state of the art for measuring that quantity.

[0075] The at least one particle beam may comprise particles from the following group: electrons, ions, atoms, molecules, and high-energy photons. Currently, electrons are preferred for analyzing and processing samples. Currently, electrons offer the best possible compromise between precise imaging and processing of samples, on the one hand, and minimal damage to the sample caused by electron bombardment, on the other.

[0076] High energy photon sources have the advantage of not being affected by electrostatic sample charges.

[0077] The particle beam may comprise electrons, and at least one parameter of at least one particle beam may comprise the impact energy of the electrons on the sample. The impact energy of the electrons (or charged particles in general) may be set by selecting an acceleration voltage for the charged particles and / or by applying a braking voltage above the sample surface. The braking voltage for the charged particles of the particle beam may be generated by applying an electrostatic potential to a metal tube mounted in the column output of the particle optics column, which metal tube is referred to in the art as a "liner tube". If a shielding grid is mounted at the column output of the scanning particle microscope, the braking voltage for the charged particles can be set by applying a corresponding potential between the shielding grid and the metal tube.

[0078] When high energy photons are absorbed by a sample, they can have enough energy to release electrons from their bonds in the sample's material. Photons from the VUV and particularly from the EUV wavelength range of the electromagnetic spectrum have sufficient energy to do this.

[0079] The method according to the present invention may further comprise providing at least one precursor gas at a processing site of the sample during irradiation of the sample with the at least one modulated particle beam.

[0080] Defects in a sample can be repaired by performing a particle beam-induced localized chemical reaction using at least one precursor gas. In the case of a material-absent defect (a visible defect), at least one precursor gas in the form of a deposition gas can be provided at the defect location. In the case of a material-excess defect (a dark defect), at least one precursor gas in the form of an etching gas can be provided at the defect location. In addition to at least one etching gas and / or at least one deposition gas, the at least one precursor gas can include at least one additive gas.

[0081] At least one deposition gas may include at least one element from the following group: metal alkyls, transition element alkyls, main group alkyls, metal carbonyls, transition element carbonyls, main group carbonyls, metal alkoxides, transition element alkoxides, main group alkoxides, metal complexes, transition element complexes, main group complexes, and organic compounds.

[0082] The metal alkyl group, transition element alkyl group, and main group alkyl group may include at least one element from the following group: cyclopentadienyl (Cp) trimethyl platinum (CpPtMe3), methylcyclopentadienyl (MeCp) trimethyl platinum (MeCpPtMe3), tetramethyltin (SnMe4), trimethylgallium (GaMe3), ferrocene (Cp2Fe), and bisarylchromium (Ar2Cr). The metal carbonyl, transition element carbonyl, and main group carbonyl may contain at least one element from the following group: chromium hexacarbonyl (Cr(CO)6), molybdenum hexacarbonyl (Mo(CO)6), tungsten hexacarbonyl (W(CO)6), dicobalt octacarbonyl (Co2(CO)8), triruthenium dodecacarbonyl (Ru3(CO)6), 12), and iron pentacarbonyl (Fe(CO)5). Metal alkoxides, transition element alkoxides, and main-group alkoxides may include at least one element from the following group: tetraethylorthosilicate (TEOS, Si(OC2H5)4) and tetraisopropoxytitanium (Ti(OC3H7)4). Metal halides, transition element halides, and main-group halides may include at least one element from the following group: tungsten hexafluoride (WF6), tungsten hexachloride (WCl6), titanium hexachloride (TiCl6), boron trichloride (BCl3), and silicon tetrachloride (SiCl4). Metal complexes, transition element complexes, and main group complexes may include at least one element from the following group: copper bis(hexafluoroacetylacetonate) (Cu(C5F6HO2)2) and dimethylgoldtrifluoroacetylacetonate (Me2Au(C5F3H4O2)). Organic compounds may include at least one element from the following group: carbon monoxide (CO), carbon dioxide (CO2), aliphatic hydrocarbons, aromatic hydrocarbons, components of vacuum pump oil, and volatile organic compounds.

[0083] At least one etching gas may include an element from the following group: a halogen-containing compound and an oxygen-containing compound. The halogen-containing compound may include at least one element from the following group: fluorine (F2), chlorine (Cl2), bromine (Br2), iodine (I2), xenon difluoride (XeF2), dixenon tetrafluoride (Xe2F4), hydrofluoric acid (HF), hydrogen iodide (HI), hydrogen bromide (HBr), nitrosyl chloride (NOCl), phosphorus trichloride (PCl3), phosphorus pentachloride (PCl5), and phosphorus trifluoride (PF3). The oxygen-containing compound may include at least one element from the following group: oxygen (O2), ozone (O3), water vapor (H2O), hydrogen peroxide (H2O2), nitrous oxide (N2O), nitrogen oxide (NO), nitrogen dioxide (NO2) and nitric acid (HNO3).

[0084] The at least one additional gas may include at least one element from the group consisting of an oxidant, a halide, and a reducing agent.

[0085] The oxidizing agent may include at least one element from the following group: oxygen (O2), ozone (O3), water vapor (H2O), hydrogen peroxide (H2O2), nitrous oxide (N2O), nitrogen oxides (NO), nitrogen dioxide (NO2), and nitric acid (HNO3). The halide may include at least one element from the following group: chlorine (Cl2), hydrochloric acid (HCl), xenon difluoride (XeF2), hydrofluoric acid (HF), iodine (I2), hydrogen iodide (HI), bromine (Br2), hydrogen bromide (HBr), nitrosyl chloride (NOCl), phosphorus trichloride (PCl3), phosphorus pentachloride (PCl5), and phosphorus trifluoride (PF3). The reducing agent may include at least one element from the following group: hydrogen (H2), ammonia (NH3), and methane (CH4).

[0086] The conductive sacrificial layer can be deposited by providing a precursor gas of Mo(CO) 6 and adding a gas of NO 2. The sacrificial layer deposited in this manner can be removed by mask cleaning.

[0087] The conductive sacrificial layer allows for spatial separation of setting the electrostatic charge from sample analysis or processing. Furthermore, setting the electrostatic charge of the sample by the conductive sacrificial layer minimizes damage to the sample caused by its irradiation.

[0088] The lateral extent of the localized particle beam-induced chemical reaction used to deposit material and to locally remove material from the sample can be in the range of <10 nm, preferably <7 nm, and most preferably <5 nm. The edge placement error of the pattern elements of the photolithographic mask (when measured and / or after it has been repaired) should be <2.1 nm, preferably <1.4 nm, and most preferably <1.0 nm. The placement of the pattern elements of the photolithographic mask can be measured with a repeatability of 0.5 nm or better. Its accuracy is in the range of 1 nm or less.

[0089] The at least one particle beam may include at least one first particle beam and at least one second particle beam.

[0090] The method according to the present invention may further comprise analyzing and / or processing the sample using at least one second modified particle beam, and setting the electrostatic charge of the sample by means of at least one first modified particle beam.

[0091] Furthermore, the described method may include imaging the sample using at least one first particle beam having a first adjustment and setting an electromagnetic charge of the sample by at least one second particle beam having the first adjustment, and processing the sample using at least one first particle beam having a second adjustment and setting the electromagnetic charge of the sample by at least one second particle beam having the second adjustment.

[0092] The at least one first particle beam may comprise a focused, adjusted particle beam for imaging and / or processing a sample with the best possible lateral spatial resolution. At least one parameter of the at least one first particle beam may be adapted to the function to be performed by the particle beam. For example, analysis of a sample may be performed using a greater impact energy of the charged particles of the particle beam than the processing to be performed on the sample. Furthermore, the at least one second particle beam may be a particle beam from a flood gun. The flood gun may use the same type of particles as the at least one first particle beam. However, the at least one first and at least one second particle beams may also use particles whose charge has a different mathematical sign. For example, the at least one first particle beam may use electrons while the flood gun may use (positively charged) ions, or vice versa.

[0093] The method according to the invention may further comprise focusing at least one first particle beam having a first adjustment of at least one parameter onto the sample and directing at least one second particle beam having a second adjustment of at least one parameter (having a flatness) onto the sample.

[0094] Furthermore, the method according to the invention may comprise scanning at least one first focused particle beam having a first adjustment of at least one parameter over a sample in an area irradiated by at least one second particle beam having a second adjustment of the at least one parameter.

[0095] The at least one first particle beam and the at least one second particle beam may use the same particle type, such as electrons. However, the at least one first particle beam and the at least one second particle beam may also use different particle types. For example, the at least one first particle beam may include photons, while the at least one second particle beam may include electrons.

[0096] The method according to the present invention may further comprise: simultaneously irradiating the sample with at least one first particle beam having a first adjustment of at least one parameter and at least one second particle beam having a second adjustment of at least one parameter. The second adjustment of the at least one second particle beam may be tuned to the first adjustment of the at least one first particle beam. The at least one first particle beam and the at least one second particle beam may contain electrons, and the first adjustment of the at least one parameter of the at least one first particle beam and the second adjustment of the at least one parameter of the at least one second particle beam may together result in a yield factor of 1, i.e., on average, two electrons are released from the sample by particles of the first particle beam and particles of the second particle beam. Irradiating the sample with two or more electron beams adjusted in this manner does not change its electrostatic charge.

[0097] Furthermore, the method according to the present invention may comprise: electrically connecting a second site to be analyzed and / or processed of the sample to at least one first site of the sample, wherein the second site to be analyzed and / or processed and the at least one first site are at a predefined distance from each other.

[0098] Conductively connecting at least one first site of the sample to a second site to be analyzed or processed means that the electrostatic potential distribution can be set at any location on the sample. In particular, the at least one first site can be selected at a location on the sample where particle irradiation does not affect the functionality of the sample.

[0099] An electrically conductive connection between a second location to be analyzed and / or processed and at least one first location can be established by depositing a conductive layer on the sample with the aid of at least one modulated particle beam and at least one precursor gas containing at least one deposition gas.

[0100] At least one site of the sample to be analyzed and / or processed may be irradiated with at least one second modified particle beam, and at least one first site of the sample may be irradiated with at least one second modified particle beam.

[0101] The method according to the present invention may comprise irradiating a second site to be analyzed and / or to be processed and at least one first site of the sample simultaneously. At least one second adjusted particle beam may irradiate a second site to be analyzed or to be processed of the sample, while at least one first adjusted particle beam may irradiate at least one first site of the sample simultaneously. In this embodiment, it is ensured that the sample has a predetermined electrostatic charge while the sample is being inspected and / or during the sample is being treated. Adjusting the at least two particle beams relative to each other particularly makes it possible to inspect or treat the sample so that it does not have electrostatic charge in substance. If at least one parameter of the at least one second particle beam is adapted when the treatment process is converted from an analytical process, then at least one parameter change of the at least one second particle beam can be compensated by carrying out corresponding parameter adaptation of at least one parameter of the at least one first particle beam.

[0102] The electrostatic charge of the sample to be compensated may cover a voltage range of -5000 V to +5000 V, -1000 V to +1000 V, -200 V to +200 V, or -50 V to +50 V.

[0103] The tuned particle beam can be used to set the electrostatic charge of the sample over a voltage range covering -3000 V to +3000 V, -1000 V to +1000 V, or -500 V to +500 V.

[0104] If the primary beam comprises an electron beam, its electrons used to set the electrostatic charge may comprise an impact energy in the range of 10 V to 5000 V, preferably 20 V to 4000 V, more preferably 30 V to 3000 V, and most preferably 50 V to 2000 V.

[0105] The sample may include a device selected from the group consisting of a photolithography mask, a nano-imprint lithography die stamp, a wafer, an integrated circuit (IC), a micro-electromechanical system (MEMS), a nano-electromechanical system (NEMS), and a photonic integrated circuit (PIC). The photolithography mask may include a transmissive or reflective mask. The mask may also include any type of mask.

[0106] The sample may include at least one defect, a conductive protective layer positioned around at least a portion thereof, and the at least one second modified particle beam may irradiate the at least one defect while the at least one first modified particle beam irradiates the conductive protective layer. The sample having the at least one defect may include a photolithography mask. The at least one defect may include a material missing defect and / or a material excess defect.

[0107] The at least one particle beam may analyze and / or process the at least one defect using a first adjustment of the at least one parameter and may irradiate the conductive protective layer using a second adjustment of the at least one parameter to set a predefined electrostatic charge of the sample in the region of the at least one defect.

[0108] The sample may contain two or more drift marks that are not aligned and therefore span a two-dimensional (2D) coordinate system. Before starting an analysis and / or processing procedure, the displacement of at least three drift marks relative to their reference position allows for the determination of distortions in the image scale or changes in the size of the 2D coordinate system caused by electrostatic charging of the sample surface.

[0109] The method according to the present invention may further comprise the steps of reducing the electrostatic charge of the sample by increasing the surface area of ​​the conductive protective layer. The capacitance of a capacitor is directly proportional to the surface area on which it can store charge. Increasing the surface area of ​​the conductive protective layer can reduce the increase or degree of electrostatic charge caused by irradiation with a particle beam that can release electrons from its bonds in the protective layer. Lower surface area charge density produces lower electrostatic field strength, thereby resulting in less deflection of the charged particle beam.

[0110] The method according to the invention may further comprise the step of determining the electrostatic charge of the sample by at least one element from: a size change of at least one reference structure of the sample or a drift correction of at least one adjusted particle beam during analysis and / or processing of the sample.

[0111] Electrostatically charging the sample results in a change in the imaging scale. Depending on the type of charge, at least one reference structure of the sample can be imaged larger or smaller by the charged particle beam. If the size of the at least one reference structure is known, for example from data from the sample manufacturer or from measurements of the at least one reference structure using an uncharged particle beam, the absolute value and mathematical sign of the electrostatic sample charge can be determined from the measured change in the size of the at least one reference structure.

[0112] Reference elements in the form of drift markers are used to measure and correct the drift between a second site to be analyzed or processed and the particle beam during analysis or processing. If two or more drift markers are used for this purpose around the second site to be analyzed or processed of the sample, the magnitude change or distortion of the imaging ratio can be determined from the positional changes of the two or more drift markers, in addition to the drift of the particle beam relative to the drift markers. This can be used to determine the magnitude and mathematical sign of the electrostatic sample charge.

[0113] The method according to the present invention may further comprise analyzing at least one defect using at least one modulated particle beam, treating a substantial portion of the defect using at least one particle beam, and treating remaining defect residue using at least one modulated particle beam. This means that the defect residue (particularly including the defect boundary) is analyzed and treated without affecting the electrostatic charge of the sample, whereas the electrostatic charge of the sample surface is not considered during treatment of the substantial portion of the defect. This process control accelerates defect repair without compromising accuracy.

[0114] The method according to the present invention may further comprise the following steps: electrostatically charging the sample within a predefined potential range by irradiating the sample with at least one particle beam having a first adjustment prior to processing and / or analyzing the sample, in particular at least one defect in the sample. The sample is then analyzed and / or processed using a second adjustment of at least one parameter of the at least one particle beam. Irradiating the sample with the second adjustment of the at least one parameter causes the sample to be electrostatically charged with an opposite mathematical sign to the electrostatic charge of the sample caused by the irradiation with the first adjustment of the at least one parameter of the at least one particle beam. The potential range may comprise an electrical potential range. The electrical potential range may comprise a voltage.

[0115] The method defined in the present application opens the possibility of charging the sample to a voltage level that does not interfere with subsequent analysis and / or subsequent processing by irradiation with a charged particle beam in a defined and controlled manner. This means that the deflection of the charged particle beam remains below an admissible critical value. The mathematical sign of the controlled electrostatic charge is selected so that the processing time can be doubled before the electrostatic charge of the sample caused by the processing has a significant impact on the analysis or processing process.

[0116] The computer program stored in the non-volatile memory may contain instructions for causing the computer system to execute the method steps of one of the aspects described above.

[0117] According to another aspect, a device for setting the electrostatic charge of a sample comprises: (a) an adjustment component for adjusting at least one parameter of at least one particle beam so that, on average, each particle of the at least one particle beam incident on the sample releases a predefined average number of electrons from the sample; (b) an irradiation component for irradiating the sample at at least one first location using at least one adjusted particle beam to set the electrostatic charge of the sample; (c) a readjustment component for readjusting at least one other particle beam to analyze and / or process at least one second location of the sample; and (d) an irradiation component for irradiating at least one second location of the sample using the readjusted at least one particle beam and / or the adjusted at least one other particle beam, wherein the at least one first location and the at least one second location are at (at least) a predefined distance and are conductively connected to each other.

[0118] According to another aspect, a device for setting the electrostatic charge of a sample comprises: (a) an adjustment component for adjusting at least one parameter of at least one particle beam so that, on average, each particle of the at least one particle beam incident on the sample releases a predefined average number of electrons from the sample; and (b) an irradiation component for irradiating the sample with the at least one adjusted particle beam to set the electrostatic charge of the sample.

[0119] The apparatus may be configured to perform the method steps in the aspects described above.

[0120] The means for adjusting at least one parameter of at least one particle beam and / or at least one other particle beam may comprise at least one element from the following group: a setting means for setting the accelerating voltage of the particles of at least one particle beam and / or at least one other particle beam; a setting means for setting the braking voltage of the particles of at least one particle beam and / or at least one other particle beam; a setting means for setting the wavelength of the particles of at least one particle beam and / or the at least one other particle beam; a setting means for setting the flux density of at least one particle beam and / or at least one other particle beam; or a setting means for setting the irradiation time of the particles of at least one particle beam and / or at least one other particle beam.

[0121] The means for setting the accelerating voltage may include setting the anode potential and / or cathode potential of the particle source for the charged particles. The means for setting the braking voltage may include setting the potential of the metal tube at the output of the particle optical column of the scanning particle microscope. Furthermore, the means for setting the braking voltage may include setting the potential between a shielding grid mounted at the output of the column and the metal tube (liner). The means for setting the wavelength of the particles of at least one particle beam may include a broadband light source (for the VUV and / or EUV wavelength ranges) and one or more bandpass filters. The means for setting the wavelength may further include a first light source emitting within a first wavelength range and at least one second light source emitting within at least one second wavelength range different from the first wavelength range. If the particle source includes a photon source, the means for setting the flux density of the at least one particle beam may include setting the beam intensity of the particle source and / or one or more adsorption filters. The means for setting the irradiation time may include a beam blanking device.

[0122] The device according to the invention may further comprise at least one element from the following group: an electron flood gun, an ion flood gun, an adjustable aperture for at least one particle beam, at least one second particle beam source for generating at least one second particle beam, or an energy selective detector for secondary electrons and / or backscattered electrons.

[0123] The submersion gun may contain charged particles having the same mathematical sign as the particles of the primary beam. The particles from the submersion gun may be charged oppositely to the particles of the primary particle beam. The adjustable aperture may comprise a condenser aperture of the particle optical column of the scanning particle microscope. The aperture width of the adjustable aperture may range from 1 nm to 1 mm, preferably from 10 nm to 300 µm, more preferably from 100 nm to 100 µm, and most preferably from 1 µm to 50 µm. The adjustable aperture may comprise an aperture system consisting of two or more apertures. The aperture or aperture system may be arranged after (downstream of) the condenser of the particle optical column of the scanning particle microscope. The second particle beam source allows the sample to be treated by a second particle beam from the second particle beam source and, at the same time, a predefined electrostatic charge of the sample to be set by irradiating at least one first point with a first particle beam from at least one first particle beam source.

[0124] The energy-selective detector may comprise a spectrometer-detector combination having a filter or filter system that discriminates between SE and BSE based on their energy. For example, a retarding field spectrometer or a deflection spectrometer using a magnetic or electrostatic field, such as a cylindrical deflection analyzer (CDA), can be used as a spectrometer or energy filter. Furthermore, a multi-channel spectrometer capable of simultaneously determining substantially the entire energy spectrum of SE and / or BSE may be used.

[0125] The device according to the invention may further comprise a displacement member for displacing the point of incidence of the at least one particle beam from at least one first point of the sample to at least one second point of the sample to be processed.

[0126] The apparatus according to the present invention is capable of providing at least one particle beam in the form of at least one electron beam, and of setting the impact energy of the at least one electron beam such that the cumulative SE and BSE generation rates (in the case of an electron beam: electrons per primary electron beam) are <1. This is true for impact energies less than a first energy threshold E1 and greater than a second energy threshold E2. When a sample is irradiated with electron impact energies within these ranges, the sample becomes negatively electrostatically charged. As previously explained, the lowest possible impact energy of the electrons in the electron beam is advantageous for performing processing on a photolithography mask, i.e., in the energy range below E1.

[0127] In the energy range E1 to E2, the sum of the yield coefficients for SE (δ) and BSE (η) is greater than 1, and the sample acquires a positive electrostatic charge. The greater the difference between the sum of the yield coefficients and 1, the faster the electrostatic charging occurs. If the impact energy of the charged particles can be freely selected within a certain range, it is advantageous to select this so that the sum of δ and η is as close to 1 as possible. Conversely, if the sample is to be charged in a controlled manner, it is advantageous to select the yield coefficients for SE and BSE for this purpose whose values ​​are as far away from 1 as possible.

[0128] At least one parameter can thus be optimized for different objectives. For example, when imaging a sample, it may be helpful to scan the sample with the maximum possible lateral resolution, for which a greater impact energy is generally desired. This results in a yield coefficient for SE and BSE in the range of >1.5. On the other hand, when processing a sample, it may be advantageous to select the impact energy of the primary electron to be as low as possible so as to minimize the lateral extent of the chemical reaction caused by the electron beam. For this impact energy of the electron, the yield coefficient is generally in the range of ≤0.5. The different electrostatic charges of the sample can be set to the desired level by irradiating the sample using a second adjustment of at least one parameter of at least one electron beam within the impact energy interval E1 to E2. Alternatively and / or additionally, the sample can be irradiated with a low-energy ion beam, which has a yield coefficient for SE and BSI <1, where BSI stands for backscattered ions. BSI occurs particularly for ions with small atomic numbers, while ions with large or high atomic numbers are mostly implanted in the sample.

[0129] The apparatus described herein may further include a gas supply system capable of providing one or more precursor gases at a processing location on the sample. The gas supply system is capable of setting the flow rate, partial pressure, and temperature of the one or more precursor gases.

[0130] The device according to the present invention may further comprise means for directing at least one particle beam onto the sample. The device may further comprise means for receiving information about at least one parameter of the at least one particle beam. The device may additionally comprise means for determining at least one adjustment of at least one parameter of the at least one particle beam. Furthermore, the device may comprise means for adjusting at least one parameter of the at least one particle beam.

[0131] The means for receiving information may have a user interface. For example, software or hardware, or a combination thereof, may enable a user of the device to provide information about at least one parameter of at least one particle beam. The device can then automatically adjust the at least one parameter using a determination means (e.g., a computer unit, a processor, etc.). Semi-automatic selection is also conceivable, in which the device offers the user a choice of adjustment options for at least one parameter of at least one particle beam and / or at least one other particle beam, said adjustment options being tailored to the respective process and / or sample to be processed and ultimately selectable by the user.

[0132] A user of the device can use the user interface to provide data regarding the material composition and / or surface profile of the sample. The device can take this data into account when determining at least one parameter. Furthermore, the device can be designed to take the sample data into account when providing adjustment options to the user.

[0133] The device according to the invention may further comprise means for performing a form of repair at at least one second location by means of at least one further particle beam, wherein the means may be further configured to irradiate at least one first location with at least one particle beam in order to set the electrostatic charge of the sample.

[0134] The apparatus may further include a database storing material compositions and surface profiles of various samples. The samples may have a code storing the sample type and associated material and surface data. The apparatus is capable of reading the sample code and determining an optimal adjustment option for at least one parameter based on the defect data.

[0135] The apparatus may be designed such that the means for receiving information is capable of receiving information identifying the first procedure as a diagnostic procedure and / or identifying the second procedure as a repair procedure.

[0136] Furthermore, it may be provided that the device for setting the electrostatic charge of the sample does not have a member for directing the particle beam onto the mask. This may be provided, for example, as a separate hardware device, which is intended to interact with the device for directing the particle beam onto the sample, for example via a (software) interface for providing information about at least one particle beam and / or at least one parameter of the first and / or second process. In addition to or as an alternative to the device for this purpose, a corresponding computer program may also be provided.

[0137] The apparatus described herein can generally be configured to perform the methods described herein. Conversely, all aspects described herein with respect to the apparatus can also be performed as method steps. BRIEF DESCRIPTION OF THE DRAWINGS

[0138] The following detailed description describes presently preferred exemplary embodiments of the invention with reference to the following drawings, in which:

[0139] Figure 1 A to Figure 1 C schematically shows the irradiation of a non-electrostatically charged photolithography mask with an electron beam, wherein the mask has a reference structure and a defect with four drift marks;

[0140] Figure 2 A to Figure 2 C schematically shows the Figure 1 A to Figure 1 Irradiation performed through a mask of C, wherein the mask has a positive electrostatic charge;

[0141] Figure 3 A to Figure 3 C schematically reproduces the pair from Figure 1 A to Figure 1 Irradiation performed through a mask of C, wherein the mask has a negative electrostatic charge;

[0142] Figure 4 Schematic illustration of the current when a conductive sample (left) and an electrically insulating sample (right) are irradiated with a particle beam;

[0143] FIG5 schematically shows the sum of the yield coefficients δ and η of secondary electrons (SE) and backscattered electrons (BSE) as a function of the particle energy of the primary beam;

[0144] Figure 6 Schematic reproduction of the imaging process of the EUV mask using an electron beam and the processing process of the EUV mask using an electron beam and a precursor gas;

[0145] Figure 7 Schematic illustration of Figure 6 Setting of the electrostatic charge of the EUV mask;

[0146] Figure 8 Schematic representation of the use of two electron beams from Figure 6 and Figure 7 Simultaneous imaging / processing and setting of electrostatic charge of EUV masks;

[0147] Figure 9 Schematic repetition of Figure 7 Setting an electrostatic charge of an EUV mask, wherein the EUV mask has a conductive sacrificial layer that is irradiated to set the electrostatic charge;

[0148] Figure 10 Schematic illustration of the setting of the electrostatic charge of a transmissive mask, wherein the transmissive mask has a conductive sacrificial layer on which reference structures in the form of drift marks are present, wherein the sacrificial layer is irradiated to set the electrostatic charge;

[0149] Figure 11 Again schematically reproduced from Figure 9 a transmissive mask wherein a first electron beam analyzes or processes the mask and a second electron beam sets its electrostatic charge;

[0150] Figure 12 The temporal distribution of the electrostatic sample charge is schematically shown in the upper image, and imaginary charges with predefined polarity are schematically illustrated in the lower image;

[0151] Figure 13 presents a schematic cross-section through a device according to the invention;

[0152] Figure 14 A flow chart illustrating a method according to the present invention; and

[0153] Figure 15 A flow chart of a further method according to the invention is reproduced. DETAILED DESCRIPTION

[0154] The presently preferred embodiments of the method according to the invention and of the device according to the invention for setting the electrostatic sample charge are explained in more detail below with reference to the examples of photolithography masks and a modified scanning electron microscope. However, the method according to the invention is not limited to the reflective and transmissive masks described below. Instead, it can be used to set the electrostatic charge of any microstructured sample, such as nanoimprint lithography die, wafers, ICs, MEMS, NEMS, and PICs. Furthermore, the device according to the invention is not limited to the examples described below. As will be readily apparent to a person skilled in the art, any scanning particle microscope (which uses, for example, a focused ion beam and / or a focused photon beam as energy source) can be used instead of the modified scanning electron microscope in question.

[0155] The presently preferred embodiments of the present invention are explained in more detail below with reference to the accompanying drawings.

[0156] Figure 1 A to Figure 1 C shows an exemplary photolithography mask 100 (hereinafter referred to as mask 100 ) having a reference structure 130 , a defect 150 , and four reference elements 160 according to one embodiment.

[0157] Figure 1 A shows a cross section through mask 100, whose surface 105 carries pattern 110. Surface 105 or pattern 110 is irradiated by electron beam 120. As an example of a particle beam 120, electron beam 120 is focused on surface 105 of mask 100 and scans across surface 105 of mask 100 to acquire an image of mask pattern 110. The impact energy of electrons 125 of electron beam 120 is typically selected so that the focused spot of electron beam 120 on mask 100 is minimized. This allows electron beam 120 to achieve maximum lateral resolution. For this purpose, electron impact energies in the range of 3 keV are typically used.

[0158] However, the impact energy of the electron beam 120 used to process the mask 100 can also be used to acquire an image of the sample (e.g., the mask 100). This procedure avoids the need to readjust the particle beam 120 or electron beam 120 when transitioning from an analysis process to a processing process. In addition, to image the sample, the electron beam 120 can be scanned multiple times over the same area of ​​the sample using different impact energies of the electrons 125 to improve the image quality.

[0159] Figure 1 B presents a schematic diagram of the reference structure 130 of the mask 100 . Figure 1The exemplary reference structure 130 of FIG. B is a square divided into nine sub-squares 140 by lines 135. The reference structures 130 can be arranged on the mask 100 at regular or irregular intervals. As explained below, the reference structures 130 can be used to determine the electrostatic charge of the mask 100 (or, more generally, the sample 100). Typically, the location and size of the reference structures 130 are known to the manufacturer of the mask 100. If this is not the case, the location and size of the reference structures 130 can be determined using, for example, a mask inspection tool.

[0160] Figure 1 C is a schematic diagram of a defect 150 in the reproduction mask 100. An exemplary defect 150 is an excess material defect or a dark defect 150. Of course, the method described here can also be used to accurately image and / or repair missing material defects or obvious defects 150. Four reference elements 160 in the form of drift marks 160 are deposited on Figure 1 C. The drift mark 160 can be deposited on the mask 100 around the defect 150 by means of an electron beam-induced deposition process while providing at least one precursor gas in the form of a deposition gas. The drift mark 160 spans a two-dimensional (2D) coordinate system. Three reference elements 160 that are not arranged in a straight line are sufficient to span the 2D coordinate system. The drift mark 160 is periodically scanned using the electron beam 120, primarily during a repair process for the defect 150, to detect drift of the defect 150 or the drift mark 160 relative to a reference position of the drift mark 160. In addition to determining the relative drift between the electron beam 120 and the drift mark 160 of the mask 100 or defect 150, changes in the position of the drift mark 160 relative to its reference position can also be used to determine the electrostatic charge of the mask 100.

[0161] In order to scan the electron beam 120 over the defect 150 in the mask 100 during the repair of the mask 100, it is advantageous to select the impact energy of the electrons 125 on the defect 150 to be as low as possible, so that the diameter of the local chemical reaction caused by the electron beam 120 is as small as possible. For this purpose, an electron impact energy of 600 eV, preferably 400 eV, and most preferably 300 eV or less is advantageous. In order to image the drift mark 160, it may be advantageous to use the electron impact energy that is also used for repairing defects, that is, an electron impact energy in the range of 600 eV, preferably 400 eV, and most preferably 300 eV or less. In addition, it may also be advantageous to perform the imaging of the drift mark using electrons 125 of the electron beam 120 with an impact energy in the range of more than 600 eV (for example 3 keV) (see below Figure 11 ).

[0162] Figure 2 A to Figure 2 C repeat again Figure 1 A to Figure 1 C. However, compared to Figure 1 A to Figure 1 C, Figure 2 A to Figure 2 The mask 100 in C has a positive electrostatic charge 200. The electric field of the positive electrostatic charge 200 bends the electron beam 220 toward the surface 105 of the mask 100. For comparison, Figure 2 A additionally illustrates using dashed lines the electron beam 120 that would be incident on the surface 105 of the mask 100 if it were not electrostatically charged. Figure 2 B presents the reference structure 130 as imaged by the electron beam 220 due to the positive electrostatic sample charge 200 of the mask 100. Figure 1 In B, the reference structure 130 of the mask 100 with positive electrostatic charge appears smaller. Figure 2 C shows the imaging of the defect 150 and the four drift marks 160, which is acquired by the electron beam 220 due to the positive electrostatic mask charge 200 of these structural elements. Figure 1 In B, Figure 2 The distance between the drift marks 160 in C appears to be decreasing.

[0163] Figure 3 A to Figure 3 C Display Figure 2 A to Figure 2 C, however, where 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 bends the path 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 incident on the uncharged mask 100 is again illustrated in dashed form. Figure 3 As shown in FIG. 3B , the deflection of the electron beam 320 caused by the negative electrostatic charge 300 is different from the deflection of the electron beam 320 caused by the negative electrostatic charge 300. Figure 1 Compared to the image in B, the imaging of the reference structure 130 is improved. The same applies to Figure 3 C. The imaging of the defect 150 and the four drift marks 160 is again referred to as Figure 1 C.

[0164] The magnitude (i.e., value) and mathematical sign of the electrostatic charges 200, 300 of the mask 100 can be determined from the size change of the reference structure 130 caused by the electrostatic charges 200, 300 of the mask 100 (or generally the sample 100). Figure 3 A. Figure 3 B. and Figure 3The electrostatic sample charge 200, 300 can also be determined from the measured displacement of the drift mark 160 relative to its reference position, as illustrated in C. This in turn applies to the absolute value and mathematical sign of the electrostatic sample charge 200, 300.

[0165] Figure 4 The left partial image shows an electrically conductive sample 400, while the right partial image shows an electrically insulating sample 450. The samples 400, 450 are arranged on an electrically conductive sample carrier 410 (stage). Figure 4 Also schematically illustrated is the current generated when a sample 400, 450 is irradiated with an electron beam 420 having a current intensity I0. Some of the electrons 125 of the primary beam 420 incident on the sample 400, 450 are backscattered by the sample 400, 450, largely independent of the conductivity of the sample 400, 450. The electrons (BSE) 430 backscattered by the sample 400, 450 form a current I directed away from the sample 400, 450. BSE The current I BSE It is proportional to the current intensity of the primary electron current I0 incident on the samples 400, 450, that is, I BSE = η·I0, where the proportionality constant η is called the output rate coefficient.

[0166] Furthermore, the incident current I0 and the current I generated by the SE 440 leaving the samples 400, 450 are SE There is usually a linear relationship between: I SE = δ·I0, with a proportionality constant δ. In the case of the conductive sample 400, the additional current I p 460 can supply charge to the sample 400, or dissipate the charge via the grounded sample carrier 410. For charge maintenance reasons, the following therefore applies to conductive samples 400: . Or rewritten as: This means that the current I p The charge excess or lack of the sample 400 is compensated, thereby preventing electrostatic charging thereof.

[0167] exist Figure 4 In the right part of the image, the non-conductive sample 450 prevents the compensation current I p The flow between the sample carrier 410 and the sample 450, that is: This also applies to ungrounded conductive samples 400, for example by virtue of the placement surface of the sample carrier 410 being made of electrically insulating material. This reduces to the equation given above for charge maintenance: Only at the moment of incidence of the electron beam 420 the current intensity on the sample 450 exactly compensates the current intensity I of the SE 440 in terms of absolute value. SEand the current intensity I of BSE 430 BSE , the sample 450 is not electrostatically charged. If this were not the case, the equilibrium value For the accumulated charge (Depending on the current intensity I0 and the size of the sample or its conductivity, a time in the range of seconds or minutes is usually sufficient for this.) The sample 450 in the form of an electrical insulator locally accumulates an electrostatic charge. On the other hand, the ungrounded conductive sample 400 Evenly distributed on sample 400.

[0168] As shown in FIG5 , the yield coefficients η and δ of BSE and SE are functions of the impact energy E0 of the primary electron beam 420. Graph 500 shows a distribution 510 of the sum of the yield coefficients η and δ as a function of the impact energy E0 of the primary electron beam 420 and is taken from the textbook "Physical Principles of Electron Microscopy," by F.R. Egerton, Springer 2005. Electron beams 420 with very low impact energies generate only a small amount of SE and BSE. This amount cannot compensate for the charge introduced into the sample 450 by the electrons 125 of the primary beam 420, and the sample 450 is therefore negatively charged 200. As the impact energy E0 increases, the number of SEs 440 and BSEs 430 generated by each incident electron 125 increases, meaning that the yield coefficients η and δ rise sharply. If the impact energy E0 reaches the first critical value E1 520, the electrons 125 incident on the sample 450 generate a total of one SE or one BSE on average. At the impact energy E0 = E1, the charge introduced into the sample 450 by the electrons 125 and the charge dissipated from the sample 450 by the SE 440 and the BSE 430 are exactly balanced with each other, and therefore the sample 450 is not electrostatically charged at the impact energy E1 520. This state I0 = I SE + I BSE This is indicated by the dashed line 550 in FIG. 5 .

[0169] As the electron impact energy E0 increases further, the yield coefficients η and δ continue to increase, reaching their maximum value at an impact energy E3. If the impact energy E0 increases beyond the value E3, although the number of electrons capable of detaching electrons 125 of the primary beam 420 from their bonds increases further, these electrons are increasingly released into deeper layers of the sample 450 and are unable to reach the sample surface 105. Consequently, the yield coefficients η and δ decrease, and thus the number of SEs 440 and BSEs 430 capable of leaving the samples 400, 450 also decreases.

[0170] At the impact energy E0 = E2, the charge introduced into the sample 450 by the electron 125 and the charge dissipated from the sample 450 by the SE 440 and the BSE 430 is I SE and I BSE The charges are balanced again. At the impact energy E2 530 of the electrons 125 of the primary beam 420, the sample 450 also has no electrostatic charge 200 or 300. If the electron impact energy E0 is within the energy range E1 to E2, the sample 450 has a positive electrostatic charge 200. Outside this energy range, that is, when E0 < E1 and E0 > E2, the sample 450 acquires a negative electrostatic charge 300.

[0171] Most known materials have an energy range E1 < E2, within which the impact energy of electron 125 results in a positive net charge 200 of the material. On the other hand, for impact energies of electron 125 outside this energy range, the material is negatively charged 300. The textbook mentioned (RF Egerton, "Physical Principles of Electron Microscopy," Springer 2005) indicates that the impact energy of electron 125 is in the range of several hundred electron volts (eV) for the lower energy threshold E1, and in the range of approximately 1 keV to 10 keV for the upper energy threshold E2.

[0172] As previously mentioned, the impact energy E0 of the electrons 125 used for imaging and processing the photolithography mask 100 is typically at different values. One advantage of the method described herein is that the impact energy E0 of the electrons 125 can be optimized for the respective function of the electrons, while the accuracy of the respective processing is not compromised by the electrostatic sample charge 200, 300.

[0173] Figure 6 Diagram 695 in FIG. 1 illustrates the processing of an EUV mask 600 by performing a localized chemical reaction on an adsorptive pattern element 640. The EUV mask 600 comprises an electrically insulating substrate 610, such as a quartz substrate. A Bragg reflector 620 is deposited on the substrate 610 in the form of a multilayer structure 620, for example, comprising alternating silicon and molybdenum layers. A conductive capping layer 630, for example, made of ruthenium (Ru), chromium (Cr), or chromium nitride (CrN), is deposited on the Bragg reflector 620. The capping layer 630 carries adsorptive conductive pattern elements 640. These may comprise, for example, tantalum (Ta), tantalum nitride (TaN), or tantalum boron nitride (TaBN).

[0174] The active portion of the EUV mask 600 is conductive in the lateral direction through the metal layer, but in the vertical direction, its non-conductive substrate 610 electrically insulates the EUV mask 600 from the sample carrier 410. In addition, the conductive cover layer 630 and the conductive layer of the Bragg mirror 620 are typically interrupted by what is known as a black border. This results in larger conductive areas of the EUV mask 600 that are separated or isolated from each other in the lateral direction by the black border and in the vertical direction by the insulating substrate 610.

[0175] Similar to defect 150, defect 650 in pattern element 640 can be an excess adsorbed material defect or a missing adsorbed material defect. A gas supply system 660 provides a precursor gas 670 in the form of a deposition gas (for excess material defects) or an etching gas (for missing material defects) at the location of defect 650 (i.e., at the processing site). Furthermore, an additive gas can be added to precursor gas 670. The electron beam 420, having a current intensity I1 (PE1), dissociates the adsorbed precursor gas 670 at the processing site and induces a localized chemical etching or deposition reaction. The impact energy E0 of the electrons 125 of the primary electron beam (PE) is selected to be as low as possible (in the range of hundreds of electron volts or less) to minimize the lateral extent of the localized chemical reaction. Within this range of impact energy E0, the currents caused by the primary electron beam in SE 440 I2 (SE) and BSE 430 I3 (BSE) are very low. These currents cannot compensate for the charge introduced into the EUV mask 600 by the primary beam 420 , and the EUV mask 600 accumulates negative electrostatic charge 300 .

[0176] The electron beam 420 can also be used to image the EUV mask 600, particularly its defects 650. Defects 650 in the EUV mask 600 can be analyzed before processing. Furthermore, after defect repair is complete, the processing site can be scanned again with the electron beam 420 to verify the success of the repair process. During these process steps, the gas supply system 660 does not provide precursor gas. To analyze the sample (i.e., the EUV mask 600 or its defects 650), the impact energy E0 of the electrons 125 of the electron beam 420 can be increased to optimize the lateral resolution of the primary beam 420 or to determine the depth profile of the sample. Changing the impact energy E0 alters the degree of electrostatic charge on the EUV mask 600. Depending on the material of the adsorptive pattern element 640 and the impact energy E0 of the electrons 125 of the primary beam 420, the sign of the electrostatic charge 200 or 300 can change.

[0177] Figure 7 The diagram 700 in FIG. 1 shows the defect 650 that has been repaired (illustrated in FIG. Figure 6The EUV mask 600 is analyzed for the setting or discharge of electrostatic charges 200, 300 experienced by the EUV mask 600. To set or remove electrostatic charges 200, 300, in a first step, the EUV mask 600 or the electron beam source 690 is moved to a location on the mask where the electron irradiation performed for discharge purposes does not have any subsequent effect on the functionality of the EUV mask 600. The impact energy E0 of the electrons of the electron beam 720 is then adjusted to produce an electrostatic charge 200, 300 value with an opposite mathematical sign to the electrostatic charge 200, 300 caused by the analysis or treatment process. Irradiation of the cover layer 630 of the EUV mask 600 with the primary electron beam PE4 720 having an impact energy E0 and a current intensity I4 (PE4) produces SE 740 with a current intensity I6 (SE6) and BSE 730 with a current intensity I5 (SE5). The difference between the current I4 (PE4) on the one hand and I5 (BSE5) and I6 (SE6) on the other hand introduces a certain amount of charge Q(t) into the cover layer 630 of the EUV mask 600, which reduces or compensates the electrostatic charge 200, 300 of the EUV mask 600 caused by the processing of the defect 650. The time required to discharge the electrostatic charge 200, 300 depends on the charge stored on the EUV mask 600. and the amount of charge generated per unit time .

[0178] refer to Figure 7 As illustrated, the process for setting a defined electrostatic charge 200, 300 can be performed before performing an analysis process, for example, to determine the location and size of a defect 650 in the EUV mask 600. This allows the location and size of the defect 650 to be determined with the greatest possible accuracy, thus establishing the prerequisites for the best possible defect repair. The electrostatic charge 200, 300 of the EUV mask 600 generated by the analysis process can be set to a desired level, for example, a charge before performing defect repair. Before imaging the processed sites of the EUV mask 600 to determine any remaining defect residues, the electrostatic charges 200 , 300 may be reset to a predefined level.

[0179] The electron beam 720 can be focused on the cover layer 630 of the EUV mask 600. However, it is also possible (especially if the EUV mask 600 allows it) to direct the primary electron beam 720 in an expanded form onto the EUV mask 600 to prevent any damage to the EUV mask 600 caused by its irradiation. When using an expanded electron beam 720, care should be taken that it does not radiate beyond the black borders of the mask 600. In this case, only some of the electrons will be available to set the electrostatic charges 200, 300. The rest will electrostatically charge areas of the EUV mask 600 in an undesirable manner.

[0180] Figure 8 The EUV mask 600 is analyzed or processed simultaneously and its electrostatic charge 200, 300 is set. Figure 8 Combine Figure 6 and Figure 7 Contents. Figure 6 Continue, in Figure 8 In the example of the invention, a first electron source 690 generates at least one other particle beam or electron beam, and uses electrons 125 of a primary electron beam 420 and a current intensity I1 (PE1) to irradiate the defect 650 in the EUV mask 600. The impact energy E0 of the electrons 125 is optimized with respect to performing an analysis process or a treatment process of the defect 650 in the EUV mask 600. There is no need to consider any damage that may be caused to the execution of the process. A second electron beam source 890 (more generally a second particle beam source 890) generates at least one particle beam, which is an electron beam 720 adjusted or tuned to the impact energy E0 of the electrons 125 to irradiate the cover layer 630 of the EUV mask, so that the current of the second electron source 890 The current of the first electron beam source 690 is precisely compensated for the difference between Therefore, the electrostatic charges 200, 300 can be prevented, or the potential of the electrostatic charges 200, 300 of the mask 600 can be set to a desired level.

[0181] After the transition from the processing of the EUV mask 600 to its analysis, accompanied by a change in the impact energy E0 of the electrons 125 of the electron beam 420 (and the deactivation of the gas supply system 660), the impact energy E0 of the electrons 125 of the electron beam 720 of the second electron source 890 can be adapted to the changed impact energy E0 of the electrons 125 of the electron beam 420.

[0182] Figure 9 The setting of the electrostatic charges 200 and 300 of the EUV mask 600 is illustrated as follows ( Figure 7 and Figure 8 An advantageous modification of the method described in . Figure 9 Repeat again from Figure 7 The electrostatic charges 200 and 300 of the EUV mask 600 are set (as shown in FIG. Figure 7(The difference is that the primary electron beam 720 is not irradiated onto the conductive cover layer 630 of the EUV mask 600, but onto the conductive sacrificial layer 920. The conductive sacrificial layer 920 is deposited onto the cover layer 630 of the EUV mask 600. To this end, the gas supply system 660 provides a precursor gas 970 at the location where the sacrificial layer 920 is to be deposited. The precursor gas 970 may contain a metal carbonyl, particularly molybdenum hexacarbonyl (Mo(CO)6). In addition, the precursor gas 970 may contain one or more additional gases. The at least one additional gas may contain an oxidizer, such as nitrogen dioxide (NO2).

[0183] The conductive sacrificial layer 920 protects the cover layer 630 of the EUV mask 600 from potential damage caused by irradiation with the electron beam 720. Thus, it serves as a protective layer. Consequently, the sacrificial layer 920 enables the use of particles of greater mass, such as ions, to set the electrostatic charge of the EUV mask 600, without the ions of the particle beam 720 being able to damage the EUV mask 600. The sacrificial layer 920 can be deposited on the cover layer 630 of the EUV mask 600 at a location that is not critical to its function and at such a large distance from the location where the defect 650 is to be treated that the defect 650 can be treated using the first radiation source 690 with the first particle beam 420, while simultaneously irradiating the sacrificial layer 920 with the second particle beam 720 to set the electrostatic charge 200, 300 of the EUV mask 600. For example, the first radiation source 690 may direct the electrons 125 onto the defects 650 , and the second radiation source 890 may irradiate ions onto the sacrificial layer 920 of the EUV mask 600 .

[0184] The sacrificial layer 920 may be removed from the EUV mask 600 after processing is completed using a mask cleaning process.

[0185] Figure 10Diagram 1095 in FIG. 1 illustrates the setting of the electrostatic charges 200 and 300 of a transmissive mask 1000. It has a non-conductive quartz substrate 1010. Adsorptive conductive pattern elements 1040 are disposed on the substrate 1010. These pattern elements may comprise, for example, chromium or molybdenum silicide. The pattern elements 1040 depicted in diagram 1095 have defects 1050. Defects 1050 may be dark defects (i.e., defects with excess adsorbent material) or visible defects (i.e., defects with missing adsorbent material). A conductive sacrificial layer 1070 or protective layer 1070 is deposited on the substrate 1010 of the transmissive mask 1000 and extends to the defective pattern elements 1040. The conductive sacrificial layer 1070 may be deposited on the substrate 1010 of the transmissive mask 1000 using a particle beam induced deposition process (by providing a precursor gas 1080 adsorbed on the substrate 1010 of the mask 1000 and an electron beam 720, such as a particle beam 720). For example, the precursor gas 1080 may include a metal carbonyl, such as chromium hexacarbonyl (Cr(CO)6) or molybdenum hexacarbonyl (Mo(CO)6), and an additive gas. The additive gas may include an oxidant, such as oxygen (O2), water (H2O), or nitrogen dioxide (NO2).

[0186] exist Figure 10 In the example shown, drift mark 1030 is deposited on sacrificial layer 1070. Drift mark 1030 can also be deposited on sacrificial layer 1070 using a particle beam-induced deposition process. Particle beam 720 from radiation source 690 can be used for this purpose. A metal carbonyl (if necessary in combination with an additive gas such as oxygen (O2), a halogen-containing gas, or nitrogen dioxide (NO2)) is again preferably used as precursor gas 1090. For example, chromium hexacarbonyl (Cr(CO)6) or molybdenum hexacarbonyl (Mo(CO)6) can again be used as the metal carbonyl. Here, a different precursor gas 1090 is preferably used to deposit drift mark 1030 than to deposit sacrificial or protective layer 1070. When drift mark 1030 is imaged using electron beam 720, in addition to topographical contrast, reference element 1030 is further distinguished from sacrificial layer 1070 by material contrast.

[0187] exist Figure 10 In the schematic cross-section shown, drift marks 1030 are deposited on a sacrificial layer 1070. Preferably, at least three drift marks 1030 are deposited on the sacrificial layer 1070 around a defect 1050. These drift marks 1030 span a 2D coordinate system in the plane of the mask 1000. Before the defect 1050 is processed, the drift marks 1030 are scanned with an electron beam 720 to determine their reference position. From the reference position of the drift marks 1030, it is also possible to determine whether the mask 1000 has an electrostatic charge 200, 300. This requires a calibration measurement in which the position of the drift marks 1030 is determined as a function of the electrostatic charge of the mask 1000.

[0188] During defect repair, processing of defect 1050 is periodically interrupted. Electron beam 720 is switched from a processing mode with a first impact energy E0(B) to an analysis mode with a second impact energy E0(A), and drift mark 1030 is scanned in the analysis mode. As previously explained, selecting E0(B) < E0(A) can be advantageous. The relative displacement between drift mark 1030 and electron beam 720 can be determined from the acquired measurement data. Furthermore, the magnitude and mathematical sign of electrostatic charge 200, 300 of mask 1000 can be determined from the displacement of drift mark 1030 relative to its reference position.

[0189] After the protective or sacrificial layer 1070 and the drift mark 1030 have been generated, the electron beam 720, after being adjusted accordingly (i.e., after the impact energy E0 has been tuned), can irradiate the sacrificial layer 1070 to set the electrostatic potential before performing the first portion of the repair of the defect 1050. After interrupting the defect repair and before scanning the drift mark 1030, the electron beam 720 can be adjusted to set the electrostatic charge 200, 300 of the mask 1000 to a desired level. The electron beam 720 then switches to analysis mode and scans the drift mark 1030. From this scan data, the drift between the defect 1050 and the electron beam 720 is determined and corrected. Furthermore, the electrostatic charge 200, 300 of the mask 1000 is determined from the scan data. If necessary, the electrostatic charge 200, 300 is set or reduced to a predefined potential before the process continues.

[0190] These process steps are repeated until the defect residues still present no longer interfere in an intolerable manner with the imaging behavior of the mask 1000 (i.e., no more developable defects are generated). After the process of repairing the defect 1050 is completed, the sacrificial layer 1070 and the drift mark 1030 located thereon are removed from the mask 1000 (preferably during a mask cleaning process).

[0191] As Figure 8 In the same way, Figure 11 The simultaneous analysis or processing of a transmissive mask 1000 and the setting of its electrostatic charge 200, 300 are illustrated using two radiation sources 690 and 890 generating at least one particle beam and at least one other particle beam. The first radiation source 690 supplies an electron beam 420, for example, with a current intensity I1 (PE11), which irradiates the mask 1000 for analyzing defects 1050, and the BSEs 430 and SEs 440 generate currents I2 (BSE2) and I3 (SE3) exiting the mask 1000. The impact energy E0 of the primary electron beam 420 is adapted to perform the defect analysis. Figure 11In the example of FIG, the second radiation source 890 irradiating onto the conductive sacrificial layer 1070 provides an electron beam 720 whose impact energy E0 and current intensity I4 (PE4) are adjusted so that the charge generated per unit time in the sacrificial layer 1070 thereby precisely balances the charge generated by the electron beam 420 in the pattern element 1040. This prevents electrostatic charging 200, 300 of the mask 1000 during the analysis process or keeps this at a predefined level.

[0192] Before repairing the defect 1050, the impact energy E0 of the electrons 125 of the electron beam 420 is optimized for the repair process. The gas supply system 660 is also activated to provide a precursor gas 1170 at the defect location. Furthermore, the impact energy E0 of the electron beam 720 from the radiation source 890 is adapted to the modified impact energy of the electron beam 420, so that the two electron beams generate equal amounts of charge per unit time in the pattern element 1040 and in the sacrificial layer 1070, respectively, but with opposite mathematical signs. This reliably prevents electrostatic charging of the sample 1000 even during sample processing.

[0193] Figure 12 Another embodiment of the method described herein for setting the electrostatic charge 200, 300 of a sample 100, 600, or 1000 is illustrated. The sample 100, 600, or 1000 is an electrical insulator, or an ungrounded electrical conductor, that locally accumulates charge when locally irradiated with a particle beam 120, 420, or 720. In the conductor, the free electrons generated by the local irradiation are distributed throughout the sample 100, 600, or 1000. The sample 100, 600, or 1000 under consideration may have larger conductive areas (however, these are isolated from each other).

[0194] The upper image 1200 shows the temporal distribution of the electrostatic charge 1210 of the uncharged sample 100, 600, 1000 at the beginning of the process. Figure 12 In the illustrated example, charge is generated in the samples 100, 600, 1000 at a constant rate over time (q(t) = c), similar to a capacitor being charged with a current that is constant over time. Other temporal distributions of electrostatic charge are of course possible. Figure 12 In the illustrated example, the samples 100, 600, 1000 are negatively charged. Therefore, the samples are irradiated with electrons having an impact energy E0 outside the energy interval E1 to E2 from FIG. 5 .

[0195] The horizontal dashed line indicates a critical charge or critical potential level 1220. In the case of electrostatic charges that are smaller than the critical potential level 1220 in absolute terms, the electric field generated by the sample 100, 600, 1000 and interfere with the charged particle beam 120, 420, 720 only to a tolerable extent. On the other hand, above the line of critical potential level 1220, the electric field caused by the electrostatic charge 1210 deviates the charged particles 125 from their desired trajectory, so that the analysis and / or processing is impaired to an extent that is no longer acceptable. The same applies to positive electrostatic charges that are (in absolute terms) larger than the positive electrostatic charge 1270 (see Figure 12 1295 ). In the upper image 1200 , the samples 100 , 600 , 1000 can be irradiated with the particle beam 120 , 420 , 720 without violating specifications in the time interval from zero until time 1230 .

[0196] Figure 12 The lower image 1295 in FIG. 5 shows the temporal distribution of the electrostatic charge of the sample 100, 600, 1000 in the upper image 1200, wherein the sample has a positive electrostatic charge 1270 at the beginning of the irradiation process, which in absolute terms reaches a critical value 1220. The positive sample charge 1270 can be achieved, for example, by irradiation with electrons 125 whose charge energy E0 is in the energy interval E1 to E2 ( FIG. 5 ), in which the irradiated sample 100, 600, 1000 is positively charged. Figure 12 In the illustrated example, due to the positive pre-charge 1270 of the sample 100, 600, 1000, the electrostatic charge 1260 is shifted from zero to a time interval 1290 compared to the partial image 1200. This makes it possible to double the time 1280 for which analysis or processing can be performed by irradiation with the charged particle beam 120, 420, 720 without violating the specifications.

[0197] Figure 13 A schematic cross section through several important components of an apparatus 1300 that may be used to set the electrostatic charge 200 , 300 of a sample 100 , 600 , 1000 , in particular a photolithographic mask 100 , 600 , 1000 , is shown. Figure 13 The exemplary apparatus 1300 in comprises a modified scanning particle microscope 1310 in the form of a scanning electron microscope (SEM) 1310 in combination with a gas supply system 660 .

[0198] The apparatus 1300 has a particle beam source 1305 in the form of an electron beam source 1305 that generates an electron beam 1315 as the particle beam 1315. Compared to an ion beam, the electron beam 1315 has the following advantages: the electrons 125 incident on the sample 1325 or the photolithography mask 100, 600, 1000 do not substantially damage the sample or the mask 100, 600, 1000. However, it is also possible to use an ion beam, an atomic beam, a molecular beam, or a photon beam ( Figure 13 not shown in the example).

[0199] The scanning particle microscope 1310 is composed of an electron beam source 1305 and a column portion 1320, in which a beam optical unit 1313 in the form of an electron optical unit of the SEM 1310 is arranged. Figure 13 In the SEM 1310 of FIG. 1 , an electron beam source 1305 is generated at a position 1322 by an imaging element disposed in a column portion 1320 and directed as a focused electron beam 1315 onto a sample 1325 (which may include a photolithography mask 100, 600, 1000). The imaging element is not illustrated in FIG. Figure 13 Thus, the beam optics unit 1313 forms an imaging system 1313 of the electron beam source 1305 of the SEM 1310. The electron beam 1315 of the electron beam source 1305 represents one possible embodiment of a particle beam or a further particle beam.

[0200] The imaging element of the cylindrical portion 1320 of the SEM 1310 can also scan the electron beam 1315 over the sample 1325. The sample 1325 can be inspected (i.e., analyzed and processed) with the aid of the electron beam 1315 of the SEM 1310. Figure 13 The aperture (not illustrated in FIG13 ) may be mounted in the cylindrical portion 1320 of the SEM 1310, preferably downstream of the condenser lens of the SEM 1310. The aperture or the aperture system may be adjusted by a setting unit 1390 of the computer system 1380 of the apparatus 1300.

[0201] In the interaction region of the sample 1325, backscattered electrons (BSE) and secondary electrons (SE) generated by the electron beam 1315 are recorded by a detector 1317. The detector 1317 arranged in the electron column 1320 is called an "in-lens detector". In various embodiments, the detector 1317 can be installed in the column 1320. The detector 1317 converts the SE generated by the electron beam 1315 and / or the BSE backscattered by the sample 1325 at the measurement point 1322 into an electrical measurement signal and forwards the electrical measurement signal to an evaluation unit 1385 of the computer system 1380 of the device 1300. The detector 1317 can include a filter or a filter system to select the SE generated by the electron beam 1315 and / or the BSE backscattered by the sample 1325 according to the energy and / or solid angle ( Figure 13 Detector 1317 is controlled by setting unit 1390 of apparatus 1300.

[0202] Exemplary apparatus 1300 may include a second detector 1319. Second detector 1319 may be designed to detect electromagnetic radiation, in particular in the X-ray range. Detector 1319 thus allows analysis of the material composition of the radiation generated by sample 1325 during its examination. Detector 1319 is likewise controlled by setting unit 1390.

[0203] The apparatus 1300 may further include a third detector ( Figure 13 The third detector is often implemented as an Everhart-Thornley detector and is typically located outside the column portion 1320. It is typically used to detect SE.

[0204] Apparatus 1300 includes a submerged gun 1303. This gun can provide low-kinetic-energy ions in the region of a sample 1325. Submerged gun 1303 can further be configured to provide electrons with a settable impact energy E0 in the region of a sample 1325 to be processed and / or analyzed. The low-kinetic-energy ions and / or electrons 125 with a settable impact energy E0 can compensate for the electrostatic charge 200, 300 of the sample 1325. Furthermore, ions or electrons from submerged gun 1303 can be used to set the electrostatic sample charge 200, 300 to a predefined charge level. Thus, submerged gun 1303 illustrates one exemplary embodiment of a particle beam.

[0205] Instead of or in addition to the submerged gun 1303, the apparatus 1300 may include a device that generates a second particle beam 720 ( Figure 13The second particle beam source 890 may have the same imaging element as the first particle beam source 1305, or an imaging element similar thereto. In addition, the second particle beam source 890 may have one or more of the detectors 1317, 1319. This means that the apparatus 1300 may include a second scanning particle microscope ( Figure 13 not shown in the example).

[0206] The apparatus 1300 may further include a grid at the output of the column portion 1320 of the modified SEM 1310 ( Figure 13 By applying a voltage between the grid and a metal tube (liner) mounted in the region of the objective lens of the column portion 1320 (the metal tube is also not shown). Figure 13 ), a settable braking voltage can be generated for the electrons 125 of the electron beam 1315, allowing their impact energy E0 to be adjusted to a desired value. Furthermore, the grid can also be used to compensate for the electrostatic charge 200, 300 of the sample 1325. Furthermore, the grid can be grounded.

[0207] In addition to the electron beam source 1305, the apparatus 1300 may include a second radiation source 890 ( Figure 13 (Not shown). The second radiation source 890 may be a second electron beam source 890, or a radiation source for another particle type (e.g., for ions, atoms, molecules, or high-energy photons).

[0208] The sample 1325 is arranged on a sample carrier 1330 or a sample carrier 1330 for testing. In the professional field, the sample carrier 1330 is also known as a "stage". Figure 13 As shown by the arrows, the sample carrier 1330 can move in three spatial directions relative to the column portion 1320 of the SEM 1310, for example, by Figure 13 In particular, the sample carrier 1330 is capable of moving the sample 1325 from at least one site 630, 920, 1070 on the sample 1325 irradiated by the adjusted particle beam 720 to a defect 150, 650, 1050 or at least one site 150, 650, 1050 to be analyzed or processed.

[0209] In addition to the translational movement, the sample carrier 1330 can be rotated at least about an axis oriented parallel to the beam direction of the particle beam source 1305. Furthermore, the sample carrier 1330 can be embodied so that it can be rotated about one or two other axes, which are arranged in the plane of the sample carrier 1330. The two or three rotation axes preferably form a rectangular coordinate system. Figure 13Presumably, due to the small distance between the end of the column portion and the sample 1325 , the sample stage 1330 can generally be rotated only to a limited extent about a rotation axis arranged in the plane of the sample stage 1330 .

[0210] The sample 1325 to be inspected can be any microstructured component or component that requires analysis and may require subsequent processing, such as repair of local defects 150, 650, 1050 in the photolithography mask 100, 600, 1000. For example, the sample 1325 can include a transmissive mask 1000 or a reflective mask 600, and / or a template for nanoimprinting technology. The transmissive mask 1000 and the reflective mask 600 can include all types of masks, such as binary masks, phase-shift masks, OMOG masks, or masks for double or multiple exposures.

[0211] Figure 13 The device 1300 may further comprise one or more scanning probe microscopes, such as an atomic force microscope (AFM) ( Figure 13 not shown), which can be used to analyze and / or process sample 1325.

[0212] exist Figure 13 In FIG. 1 , a scanning electron microscope 1310 is shown by way of example operating in a vacuum chamber 1301. In order to generate and maintain the required reduced pressure in the vacuum chamber 1301, Figure 13 The SEM 1310 in FIG. 1 has a pump system 1307 .

[0213] The device 1300 includes a computer system 1380. The computer system includes a setting unit 1390 configured to set the impact energy E0 of the electrons 125 of the electron beam 1315 to a predefined value. For this purpose, an evaluation unit 1385 can set the acceleration voltage of the electrons 125 of the electron beam 1315, as well as the braking voltage thereof.

[0214] Computer system 1380 may further include an interface 1370, through which computer system 1380 may receive information about sample 1325, such as its material composition and / or its surface profile. Computer system 1380 may also receive information about defects 150, 650, and 1050 in sample 1325. Computer system 1380 may also include a user interface 1375, through which a user provides computer system 1380 with the impact energy E0 of electrons 125 of electron beam 1315. However, the user may also provide computer system 1380 with only a possible energy range for setting the impact energy E0 of electrons 125 of electron beam 1315 via user interface 1375. Computer system 1380 may also determine the impact energy E0 of electrons 125 of electron beam 1315, and setting unit 1390 of computer system 1380 may also set the acceleration voltage and / or braking voltage.

[0215] Computer system 1380 may also include a scanning unit 1382 that scans electron beam 1315 over sample 1325. Setting unit 1390 may be further configured to set various parameters of modified scanning particle microscope 1310 of apparatus 1300. Setting unit 1390 may further control the micromanipulator and rotation of sample stage 1330. Computer system 1380 may additionally be configured to control submersion gun 1303 and / or second radiation source 890, or to scan over sample 1325.

[0216] Furthermore, an evaluation unit 1385 of the computer system 1380 may analyze the measurement signals from the detectors 1317 and 1319 and generate therefrom an image of the sample 1325 that can be displayed by the display 1395. In particular, the evaluation unit 1385 may be designed to determine the location and contours of missing material defects 650, 1050 and / or excess material defects 150, 650, 1050 in the sample 1325 (e.g., the photolithography mask 100, 600, 1000) from the measurement data from the detector 1317.

[0217] Evaluation unit 1385 may additionally include one or more algorithms that allow the magnitude and mathematical sign of the electrostatic charge 200, 300 of sample 1325 to be determined from images of one or more reference structures 130. Evaluation unit 1385 may further include one or more algorithms designed to determine the magnitude and mathematical sign of the electrostatic sample charge 200, 300 from the positional shifts of three or more drift markers 1030. Evaluation unit 1385 also includes one or more algorithms designed to determine the impact energy E0 of particles 125 of particle beam 1315 used to set or compensate for the electrostatic sample charge 200, 300 based on the determined electrostatic charge 200, 300, the material composition of sample 1325, and its surface profile. The algorithms of evaluation unit 1385 may be implemented using hardware, software, or a combination thereof. In particular, one or more algorithms may be implemented using an application-specific integrated circuit (ASIC) and / or a field-programmable gate array (FPGA).

[0218] The computer system 1380 and / or the evaluation unit 1385 may include a memory, preferably a non-volatile memory ( Figure 13 The computer system 1380 may include a computer system (not shown) that stores a material database for sample 1325 and models of repair forms for different mask types 100, 600, and 1000. Evaluation unit 1385 may be configured to calculate a repair form for one or more defects 150, 650, and 1050 in lithography masks 600 and 1000 based on the repair model from measurement data from detector 1317. Furthermore, computer system 1380 may include an interface 1370 for exchanging data with the Internet, an intranet, and / or some other device. Interface 1370 may include a wireless or wired interface. Evaluation unit 1385 may provide data to setting unit 1390 to allow setting unit 1390 to automatically adjust (i.e., without user interaction) the impact energy E0 of particles 125 in particle beam 1315.

[0219] The evaluation unit 1385 and / or the setting unit 1390 may be integrated into the computer system 1380, such as Figure 13 However, the evaluation unit 1385 and / or the setting unit 1390 may also be implemented as independent units within or outside the device 1300. In particular, the evaluation unit 1385 and / or the setting unit 1390 may be designed to perform some of their tasks by means of dedicated hardware.

[0220] The computer system 1380 may be further integrated into the device 1300, or may be designed as a standalone device ( Figure 13(not shown). Computer system 1380 may be implemented using hardware, software, firmware, or a combination thereof.

[0221] The gas supply system 660 implemented by the apparatus 1300 is discussed below. As previously explained, the sample 1325 is disposed on the sample stage 1330. The imaging element of the column portion 1320 of the SEM 1310 is capable of focusing the electron beam 1315 and scanning it over the sample 1325. The electron beam 1315 of the SEM 1310 can be used to induce a particle beam-induced deposition process (electron beam-induced deposition, EBID) and / or a particle beam-induced etching process (electron beam-induced etching, EBIE) . Figure 13 The exemplary apparatus 1300 in FIG. 1 has three different supply vessels 1340 , 1350 , and 1360 for storing various precursor gases to perform these processes.

[0222] The first supply container 1340 stores a precursor gas, such as a metal carbonyl such as chromium hexacarbonyl (Cr(CO)6) or molybdenum hexacarbonyl (Mo(CO)6). Using the precursor gas stored in the first supply container 1340, material missing from the photolithography mask 100, 600, or 1000 can be deposited thereon, for example, in a localized chemical deposition reaction. Furthermore, a protective layer 1070 or a sacrificial layer 1070 can be deposited on the mask 600 or 1000 using the precursor gas stored in the first supply container 1340. Furthermore, a drift mark 1030 can be deposited on the mask 600 or 1000 or the sacrificial layer 1070 using the precursor gas stored in the first supply container 1340.

[0223] The electron beam 1315 of the SEM 1310 serves as an energy supplier for splitting the precursor gas stored in the first supply container 1340 at the location where the material is to be deposited on the sample 1325. This means that the combined supply of the electron beam 1315 and the precursor gas results in an EBID process being performed for the localized deposition of missing material (e.g., material missing from the mask 600, 1000).

[0224] Electron beam 1315 can be focused to a spot diameter in the range of several nanometers. The interaction region, or scattering cone, in which electron beam 1315 generates SE depends primarily on the energy of electron beam 1315 and secondarily on the composition of the material on which electron beam 1315 is incident. The diameter of the interaction region reaches values ​​in the low single-digit nanometer range. Therefore, the diameter of the scattering cone of electron beam 1315 limits the achievable resolution limit when performing localized particle beam-induced reactions. This resolution limit is currently in the single-digit nanometer range.

[0225] exist Figure 13 In the illustrated apparatus 1300, a second supply container 1350 stores an etching gas that allows for a localized electron beam induced etching (EBIE) process. This EBIE process can remove excess material from the sample 1325, for example, excess material from the pattern elements 640 and 1040 can be removed from the masks 600 and 1000. For example, the etching gas may contain xenon difluoride (XeF2), a halogen, or nitrosyl chloride (NOCl).

[0226] Additive or additional gas may be stored in the third supply container 1360, which gas (if necessary) can be added to the etching gas remaining available in the second supply container 1350, or to the precursor gas stored in the first supply container 1340. As an alternative, the third supply container 1360 may store a second precursor gas or a second etching gas.

[0227] exist Figure 13 In the illustrated apparatus 1300, each of the supply containers 1340, 1350, and 1360 of the gas supply system 660 has its own control valve 1342, 1352, and 1362 to monitor or control the amount of the corresponding gas provided per unit time, that is, the volume flow rate of the gas at the site 1322 where the electron beam 1315 is incident on the sample 1325. The control valves 1342, 1352, and 1362 can be controlled or monitored by a setting unit 1390 of a computer system 1380. This component allows the partial pressure conditions of one or more gases provided at the processing location for performing the EBID and / or EBIE process to be set within a wide range.

[0228] In addition, Figure 13 In the exemplary apparatus 1300 , each supply vessel 1340 , 1350 , and 1360 has its own gas feeder system 1345 , 1355 , and 1365 , the ends of which have nozzles 1347 , 1357 , and 1367 near the point of incidence of the electron beam 1315 on the sample 1325 .

[0229] The supply containers 1340, 1350 and 1360 may have their own temperature setting elements and / or control elements that allow cooling and heating of the corresponding supply containers 1340, 1350 and 1360. This allows the supply containers 1340, 1350 and 1360 to be heated and cooled at the respective optimum temperatures ( Figure 13 The precursor gases are stored and, in particular, supplied to the supply vessels 1340, 1350, and 1360 (not shown). A setting unit 1390 is capable of controlling the temperature setting elements and temperature control elements of the supply vessels 1340, 1350, and 1360. During the EBID and EBIE processes, the temperature setting elements of the supply vessels 1340, 1350, and 1360 can further be used to set the vapor pressure of the precursor gases stored therein by selecting an appropriate temperature.

[0230] The apparatus 1300 may include one or more supply containers 1340 to store two or more precursor gases. The apparatus 1300 may further include one or more supply containers 1350 to store two or more etching gases ( Figure 13 not shown).

[0231] Figure 14 Flowchart 1400 further represents the basic steps of a method for setting the electrostatic charge 200, 300 of a sample 100, 600, 1000, 1325. The method starts at step 1410. In step 1420, at least one parameter of at least one particle beam 120, 420, 720, 1315 is adjusted so that, on average, each particle 125 of the at least one particle beam 120, 420, 720, 1325 incident on the sample 100, 600, 1000, 1325 releases a predefined average number of electrons from the sample 100, 600, 1000 to be repaired. The at least one parameter can be adjusted, for example, by setting the impact energy E0 of the particles 125 of the at least one particle beam 120, 420, 720, 1325. For this purpose, the setting unit 1390 of the device 1300 can therefore set or adjust an acceleration voltage and / or a braking voltage for the particles 125 of the at least one particle beam 120 , 420 , 720 , 1325 .

[0232] In step 1430 , at least one modulated particle beam 720 irradiates the sample 100 , 600 , 1000 , 1325 at at least one first point 630 , 920 , 1070 to set the electrostatic charge 200 , 300 of the sample 100 , 600 , 1000 , 1325 .

[0233] In step 1440 , at least one particle beam 120 , 420 , 720 , 1315 is realigned and / or at least one other particle beam 120 , 420 , 1315 is adjusted to analyze and / or process at least one second site 150 , 650 , 1050 of the sample 100 , 600 , 1000 , 1325 .

[0234] Next, in step 1450, the re-adjusted particle beam 720 or the adjusted other particle beam 420 is used to irradiate the sample 100, 600, 1000, 1325 at at least one second location 150, 650, 1050, wherein at least one first location 630, 920, 1070 and at least one second location 150, 650, 1050 are at a predefined distance and are electrically connected to each other.

[0235] The method ends at step 1460.

[0236] at last, Figure 15Flowchart 1500 in FIG. 1 represents the basic steps of another method for setting the electrostatic charge 200, 300 of a sample 100, 600, 1000, 1325. The method starts at step 1510. In step 1520, at least one parameter of at least one particle beam 120, 420, 720, 1325 is adjusted so that, on average, each particle 125 of the at least one particle beam 120, 420, 720, 1325 incident on the sample 100, 600, 1000, 1325 releases a predefined average number of electrons from the sample 100, 600, 1000, 1325. The at least one parameter can be adjusted, for example, by setting an impact energy E0 of the particles 125 of the at least one particle beam 120, 420, 720, 1325. For this purpose, the setting unit 1390 of the device 1300 can therefore set or adjust an acceleration voltage and / or a braking voltage for the particles 125 of the at least one particle beam 120 , 420 , 720 , 1325 .

[0237] In step 1530 , the sample 100 , 600 , 1000 , 1325 is irradiated with the at least one adjusted particle beam 720 to set the electrostatic charge 200 , 300 of the sample 100 , 600 , 1000 , 1325 . The method ends in step 1540 .

Claims

1. A method (1400) for setting an electrostatic charge (200, 300) of a sample (100, 600, 1000, 1325), comprising: a. adjusting (1420) at least one parameter of at least one particle beam (120, 420, 720, 1315) so that, on average, each particle (125) of the at least one particle beam (120, 420, 720, 1315) incident on the sample (100, 600, 1000, 1325) releases a predefined average number of electrons from the sample (100, 600, 1000, 1325); b. irradiating (1430) the sample (100, 600, 1000, 1325) at at least one first point (630, 920, 1070) with at least one adjusted particle beam (720) to set the electrostatic charge (200, 300) of the sample (100, 600, 1000, 1325); c. re-adjusting (1440) at least one parameter of the at least one particle beam (120, 420, 720, 1315) and / or adjusting (1440) at least one other particle beam (720) to enable analysis and / or processing of at least one second site (150, 650, 1050) of the sample (100, 600, 1000, 1325); and d. Irradiating (1450) the at least one second site (150, 650, 1050) of the sample (100, 600, 1000, 1325) using the readjusted at least one particle beam (120, 420, 720, 1315) and / or the adjusted at least one other particle beam (120, 420, 1315), wherein the at least one first site (630, 920, 1070) and the at least one second site (150, 650, 1050) are at a predefined distance and are electrically connected to each other.

2. The method (1400) of claim 1, wherein steps b. and d. are performed simultaneously.

3. The method (1400) of claim 1, wherein steps b. and d. are performed sequentially.

4. The method (1400) of claim 1 or 3, wherein the at least one particle beam (120, 420, 720, 1315) irradiates the at least one first location (630, 920, 1070) with a first adjustment, irradiates the at least one second location (150, 650, 1050) with a second adjustment for processing purposes, and / or irradiates the at least one second location (150, 650, 1050) with a third adjustment for analysis purposes.

5. The method (1400) of claim 1 or 2, wherein the at least one particle beam (720) irradiates the at least one first point (630, 920, 1070) with a first adjustment, and the at least one other particle beam (120, 420, 1315) irradiates the at least one second point (150, 650, 1050) with a first adjustment, to process the at least one first point (630, 920, 1070) with a second adjustment, and the at least one other particle beam (120, 420, 1315) irradiates the at least one second point (150, 650, 1050) with a second adjustment, to analyze the at least one first point (630, 920, 1070).

6. A method (1400) as described in any of the preceding claims, wherein the predefined distance is selected so that the irradiation (1430) of the at least one first point (630, 920, 1070) using the at least one particle beam (720) at the predefined distance does not substantially affect the irradiation (1450) of the at least one second point (150, 650, 1050) using the at least one particle beam (120, 420, 720, 1315) or the at least one other particle beam (120, 420, 1315) to analyze and / or process the at least one second point (150, 650, 1050) of the sample (100, 600, 1000, 1325).

7. A method (1400) as described in any of the preceding claims, wherein the predefined distance between the at least one first location (630, 920, 1070) and the at least one second location (150, 650, 1050) includes at least the length or width of the scanning area of ​​the at least one particle beam (120, 420, 720, 1315) and / or the at least one other particle beam.

8. A method (1400) as described in any of the preceding claims, wherein, in order to irradiate the at least one second site (150, 650, 1050), irradiating the at least one second site (150, 650, 1050) includes: providing at least one precursor gas (670) at the at least one second site (150, 650, 1050).

9. A method (1400) as described in any of the preceding claims, wherein at the at least one first point (630, 920, 1070), the concentration of the at least one precursor gas (670) is less than 50%, preferably less than 10%, more preferably less than 1%, and most preferably less than 0.1% of the maximum concentration at the at least one second point (150, 650, 1050) to be treated.

10. The method (1400) of any of the preceding claims, wherein the predefined distance between the at least one first location (630, 920, 1070) and the at least one second location (150, 650, 1050) is at least 20 µm, preferably at least 200 µm, more preferably at least 2 mm, and most preferably at least 10 mm.

11. The method (1400) of any preceding claim, further comprising: To treat the at least one second site (150, 650, 1050), interrupting the irradiation of the at least one particle beam (120, 420, 720, 1315) and / or the at least one other particle beam (120, 420, 1315); determining a location of at least one drift marker (1030); determining a deviation of the determined position of the at least one drift marker (1030) from a reference position; Correcting the positioning of the at least one particle beam (120, 420, 720, 1315) and / or the at least one other particle beam (120, 420, 1315) incident on the at least one second location (150, 650, 1050) by means of the determined deviation; and The irradiating (1450) is continued with the at least one particle beam (120, 420, 720, 1315) and / or with the at least one other particle beam (120, 420, 1315) to treat the at least one second site (150, 650, 1050).

12. A method (1500) for setting an electrostatic charge (200, 300) of a sample (100, 600, 1000, 1325), comprising: a. adjusting (1520) at least one parameter of at least one particle beam (120, 420, 720, 1315) so that, on average, each particle (125) of the at least one particle beam (120, 420, 720, 1315) incident on the sample (100, 600, 1000, 1325) releases a predefined average number of electrons from the sample (100, 600, 1000, 1325); b. irradiating (1530) the sample (100, 600, 1000, 1325) with at least one modulated particle beam (720) to set the electrostatic charge (200, 300) of the sample (100, 600, 1000, 1325); and c. providing at least one precursor gas (670) at a processing site (1322) of the sample (100, 600, 1000, 1325) to repair at least one defect (150, 650, 1050) in the sample (100, 600, 1000, 1325) during irradiation of the sample (100, 600, 1000, 1325) with the at least one modulated particle beam (420).

13. The method (1400, 1500) of any of the preceding claims, wherein the adjustment (1420, 1440, 1520) of at least one parameter of the at least one particle beam (120, 420, 720, 1315) and / or the at least one other particle beam (120, 420, 1315) comprises changing at least one parameter from the following group: an impact energy of particles (125) of the at least one particle beam (120, 420, 720, 1315) and / or the at least one other particle beam (120, 420, 1315) incident on the sample (100, 600, 1000, 1325), a velocity of the at least one particle beam (120, 420, 720, 1315), and a velocity of the at least one particle beam (120, 420, 720, 1315). and / or the wavelength of the particles (125) of the at least one other particle beam (120, 420, 1315) incident on the sample (100, 600, 1000, 1325), the flux density of the particles (125) of the at least one other particle beam (120, 420, 720, 1315) and / or the at least one other particle beam (120, 420, 1315) incident on the sample (100, 600, 1000, 1325), and the irradiation time of the particles (125) of the at least one other particle beam (120, 420, 720, 1315) and / or the at least one other particle beam (120, 420, 1315) incident on the sample (100, 600, 1000, 1325).

14. The method (1400, 1500) of any of the preceding claims, wherein the adjustment (1420, 1440, 1520) of the at least one parameter further comprises at least one of: determining the current intensity and / or flux density of the at least one particle beam (720), and determining the irradiation time of the sample (100, 600, 1000, 1325) using the at least one particle beam (120, 420, 720, 1315) and / or the at least one other particle beam (120, 420, 1315).

15. The method (1500) of any one of claims 12 to 14, wherein the at least one particle beam (120, 420, 720, 1315) comprises at least one first particle beam (720) and at least one second particle beam (420).

16. The method (1500) of claim 15, further comprising: analyzing and / or processing the sample (100, 600, 1000, 1325) using the at least one second adjusted particle beam (420), and setting the electrostatic charge (200, 300) of the sample (100, 600, 1000, 1325) by the at least one first adjusted particle beam (720).

17. The method (1500) of claim 15 or 16, further comprising: simultaneously irradiating the sample (100, 600, 1000, 1325) with the at least one first particle beam (720) having the first adjustment and the at least one second particle beam (420) having the second adjustment.

18. The method (1500) as described in any one of claims 12 to 17 further comprises: electrically connecting a second site (150, 650, 1050) of the sample (100, 600, 1000, 1325) to be analyzed and / or processed to at least one first site (920) of the sample (100, 600, 1000, 1325), wherein the second site (150, 650, 1050) to be analyzed and / or processed and the at least one first site (920) are a predetermined distance apart from each other.

19. The method (1500) of any one of claims 12 to 18, wherein the sample (100, 600, 1000, 1325) comprises at least one defect (150, 650, 1050) around at least a portion of which a conductive protective layer (1070) is positioned, and wherein the at least one second modulated particle beam (420) irradiates the at least one defect (150, 650, 1050) and the at least one first modulated particle beam (720) irradiates the conductive protective layer (1070).

20. The method (1400, 1500) as claimed in any of the preceding claims, further comprising the step of determining the electrostatic charge (200, 300) of the sample (100, 600, 1000, 1325) by at least one element from: a size change of at least one reference structure (130) of the sample (100, 600, 1000, 1325) during analysis and / or processing of the sample (100, 600, 1000, 1325), or a drift correction of the at least one adjusted particle beam (420, 720).

21. The method (1400, 1500) as claimed in any of the preceding claims, further comprising the following steps: electrostatically charging (200, 300) the sample (100, 600, 1000, 1325) in a predefined potential interval (1270) by irradiating the at least one particle beam (120, 420, 720, 1315) with a first adjustment before processing and / or analyzing the sample (100, 600, 1000, 1325), in particular at least one defect (150, 650, 1050) in the sample (100, 600, 1000, 1325) with at least one second adjustment of the at least one particle beam (120, 420, 720, 1315).

22. A computer program stored in a non-volatile memory and comprising instructions for causing a computer system to execute the method steps as claimed in any one of claims 1 to 21.

23. A device (1300) for setting an electrostatic charge (200, 300) of a sample (100, 600, 1000, 1325), comprising: a. an adjusting member for adjusting (1420) at least one parameter of at least one particle beam (120, 420, 720, 1315) so that, on average, each particle (125) of the at least one particle beam (120, 420, 720, 1315) incident on the sample (100, 600, 1000, 1325) releases a predefined average number of electrons from the sample (100, 600, 1000, 1325); b. an irradiation member for irradiating (1430) the sample (100, 600, 1000, 1325) at at least one first point (630, 920, 1070) with at least one adjusted particle beam (720) to set the electrostatic charge (200, 300) of the sample (100, 600, 1000, 1325); c. adjustment means for adjusting (1440) at least one other particle beam (720) to analyze and / or process at least one second site (150, 650, 1050) of the sample (100, 600, 1000, 1325); and d. An irradiation component for irradiating (1450) the at least one second site (150, 650, 1050) of the sample (100, 600, 1000, 1325) using the readjusted at least one particle beam (120, 420, 720, 1315) and / or the adjusted at least one other particle beam (120, 420, 1315), wherein the at least one first site (630, 920, 1070) and the at least one second site (150, 650, 1050) are at a predefined distance and are electrically conductively connected to each other.

24. A device (1300) for setting an electrostatic charge (200, 300) of a sample (100, 600, 1000, 1325), comprising: a. an adjusting member for adjusting (1520) at least one parameter of at least one particle beam (120, 420, 720, 1315) so that, on average, each particle (125) of the at least one particle beam (120, 420, 720, 1315) incident on the sample (100, 600, 1000, 1325) releases a predefined average number of electrons from the sample (100, 600, 1000, 1325); b. irradiation means for irradiating (1530) the sample (100, 600, 1000, 1325) with at least one adjusted particle beam (720) to set the electrostatic charge (200, 300) of the sample (100, 600, 1000, 1325); and c. Providing means for providing (660) at least one precursor gas (670) at a processing site (1322) of the sample (100, 600, 1000, 1325) during irradiation of the sample (100, 600, 1000, 1325) with the at least one modulated particle beam (420) to repair at least one defect (150, 650, 1050) in the sample (100, 600, 1000, 1325).

25. The apparatus (1300) of claims 23 and 24, wherein the apparatus (1300) is configured to perform the method steps of claims 1 to 21.

26. The device (1300) as claimed in claims 23 to 25, wherein the adjustment means for adjusting (1420, 1440, 1520) at least one parameter of the at least one particle beam (120, 420, 720, 1315) and / or the at least one other particle beam (120, 420, 1315) comprises at least one element: means for setting an acceleration voltage of the particles (125) of the at least one particle beam (120, 420, 720, 1315) and / or the at least one other particle beam (120, 420, 1315); means for setting an acceleration voltage of the at least one particle beam (120, 420, 720, 1315) and / or the at least one other particle beam (120, 420, 1315); 420, 1315), a component for setting a braking voltage of the particles (125) of the at least one particle beam (120, 420, 720, 1315) and / or the at least one other particle beam (120, 420, 1315), a component for setting a wavelength of the particles (125) of the at least one particle beam (120, 420, 720, 1315) and / or the at least one other particle beam (120, 420, 1315), a component for setting a flux density of the at least one particle beam (120, 420, 720, 1315) and / or the at least one other particle beam (120, 420, 1315), or a component for setting an irradiation time of the particles (125) of the at least one particle beam (120, 420, 720, 1315) and / or the at least one other particle beam (120, 420, 1315).

27. The device (1300) as claimed in any one of claims 23 to 26, further comprising at least one element from the following: a flooded electron gun (1303), a flooded ion gun (1303), an adjustable aperture for the at least one particle beam (120, 420, 720, 1315), at least one second particle beam source (890) for generating at least one second particle beam (120, 420, 1315), or an energy selective detector (1317) for secondary electrons and / or backscattered electrons.

28. The device (1300) as described in any one of claims 23 to 27 further comprises: a component for shifting the incident point of the at least one particle beam (120, 420, 720, 1315) from at least one first point (630, 920, 1070) of the sample (100, 600, 1000, 1325) to at least one second point (150, 650, 1050) of the sample (100, 600, 1000, 1325).

29. The device as described in any one of claims 23 to 28 further comprises: a component for performing a repair form at the at least one second location (150, 650, 1050) by the at least one other particle beam (120, 420, 1315), wherein the component is further configured to use the at least one particle beam (720) to irradiate the at least one first location (630, 920, 1070) to set the electrostatic charge (200, 300) of the sample (100, 600, 1000, 1325).

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