Method and device for contactlessly setting an electrostatic charge on a specimen - Patent Application 20070122997

Abstract

The present application relates to a method (1400) and a device (1300) for setting an electrostatic charge (200, 300) on a sample (100, 600, 1000, 1325). The method (1400) includes: (a) adjusting (1420) at least one parameter of at least one particle beam (120, 420, 720, 1315) so that each particle (125) of the at least one particle beam (120, 420, 720, 1315) incident on the sample (100, 600, 1000, 1315) emits, on average, a predetermined average number of electrons from the sample (100, 600, 1000, 1315); and (b) irradiating (1430) the sample (100, 600, 1000, 1315) with the at least one adjusted particle beam (720) to set an electrostatic charge (200, 300) on the sample (100, 600, 1000, 1315).

Description

[Technical Field]

[0001] This patent application claims priority to German Patent Application No. 102023200591.3 entitled "Method and Device for Contactless Setting of an Electrostatic Charge on a Sample" (Method and Device for Contactless Setting of an Electrostatic Charge on a Sample), filed with the German Patent and Trademark Office on January 25, 2023, which is incorporated by reference in its entirety into the present patent application.

[0002] The present invention relates to a method and device for contactlessly setting an electrostatic charge on a specimen, in particular a lithography mask. [Background technology]

[0003] As a result of the continuous increase in integration density in microelectronics, lithography masks are required to image ever-smaller structural features 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 are mainly used for exposure purposes; these lasers emit light at a wavelength of 193 nm. Intensive research is being conducted on light sources emitting in the extreme ultraviolet (EUV) wavelength range (10 nm to 15 nm) and corresponding EUV masks. The resolution capabilities of the wafer exposure process have been improved by the simultaneous development of several variants of conventional lithography masks. Examples are phase masks or phase-shift masks and masks for multiple exposures.

[0004] Due to ever-decreasing dimensions of structural elements, lithography masks, especially photolithography masks, cannot always be produced without defects. Due to the high production costs of photomasks, defective photomasks are repaired whenever possible. Two important groups of defects in photolithography masks are dark defects, which are areas where absorber or phase-shifting material is present but should not be. These defects are repaired by removing the excess material, preferably using a localized etching process. Second, there are so-called bright defects, which are defects in a photomask that, upon optical exposure in a wafer stepper or wafer scanner, have a higher optical transmittance than an identical reference location without a defect. In a mask repair process, these defects can be removed by depositing a material with suitable optical properties. The optical properties of the material used for repair should ideally match those of the absorber or phase-shifting material.

[0005] Defects can be further subdivided into printable defects and non-printable defects. During wafer exposure, a photomask with printable defects or printable mask defects will produce a pattern on the wafer that does not meet all of the design specifications. In contrast, during wafer exposure, a mask with one or more non-printable defects will produce a pattern on the wafer that meets all of the design specifications. When defects are referred to below, it should be understood to mean only printable defects, i.e., print defects.

[0006] U.S. Patent Application Publication No. 2002 / 0070340 describes an electron microscope (LEEM) that uses two beams containing low-energy electrons. The low-energy beam ejects less than one electron from the sample for each electron of the primary beam that is incident on the sample, compensating for the greater than one yield of the high-energy primary beam, thereby preventing electrostatic charging of the sample.

[0007] Applicant develops and manufactures metrology equipment for analyzing photolithography masks, for example sold under the trademarks PROVE®, AIMS™, or WLCD. Applicant also develops and sells photolithography mask repair devices, for example known under the trademarks MeRiT®, RegC®, or ForTune®.

[0008] Repair is typically performed using a particle beam (e.g., including electrons, ions, atoms, molecules, and / or high-energy photons) with specific beam parameters. The particle beam, together with a precursor gas to which the sample, e.g., a mask, is exposed, excites a local chemical reaction on the sample, e.g., a photomask, based on defined process parameters. In this case, material can be locally deposited on the sample or locally removed from the sample.

[0009] Inspection and / or processing of specimens using particle beams often involves the introduction and / or generation of charge, usually electrons, into the specimen. Charge can be accumulated by charged particles and / or EUV photons, for example, through mechanical processes and / or during processing and / or imaging of specimens such as semiconductor substrates. This often results in electrical or electrostatic charging of the specimen. Charging causes distortions in the imaging of analyzed features, such as defects, thereby reducing the quality of the imaging of the defect features and / or the process of processing the defects in the specimen.

[0010] In conductive samples, locally generated charges are distributed throughout the sample, resulting in a global electrostatic charge. Grounding the sample can largely prevent electrostatic charging. In non-conductive samples, localized charge generation, along with the associated electric field, leads to localized electrostatic charging of the sample. As described in EP 1 587 128, a metal aperture mounted slightly above the sample can significantly reduce the effect of electrostatic charging on the charged particle beam. However, apertures can adversely affect sample imaging and / or processing, making them unusable in some applications.

[0011] Flood guns or plasmas are sometimes used to compensate for electrostatic charging. However, when used, the area to be analyzed or processed is usually directly irradiated over a large area. In the case of mask repair, there is a risk of undesirable interactions with particle beam-induced processes. In addition, the supply of plasma-charged particles over a large area can lead to chemical changes in the sample's components. Furthermore, in both cases, it is not possible to set a specific charge state of the sample. In addition, electrostatic charges during the analysis and / or processing process cannot always be determined in advance with the required accuracy. This makes computer-aided correction of beam deflections caused by charge accumulation on the sample difficult.

[0012] U.S. Patent No. 6,734,443 describes a method for removing contaminants and controlling localized electrostatic discharge during the manufacturing process of semiconductor components, such as photolithography 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 before assembly. For EUV masks, this wavelength range is 1 nm to 157 nm, and for masks with 157 nm actinic wavelengths, the range is 157 nm to 206 nm.

[0013] To minimize the effects of particle beam drift on a non-conductive sample, such as a transmissive photomask, during the processing of the analyzed portion and / or during data acquisition from the analyzed portion, one or more reference structures (drift markers) described in U.S. Patent Application Publication No. 2012 / 0273458 are often placed near the defect portion of the sample and imaged periodically during the imaging and / or processing process. The measured deviation is used to correct the beam position (drift correction, DC). Generally, the particle dose used to repair the defect on the sample is different from the particle dose used to analyze the reference structure and / or the defective structure on the sample. If the repaired portion and the reference structure are not electrically connected to each other, different amounts of charge are generated at the different portions, and therefore the beam deflection detected at the reference portion will not match the beam deflection at the processing portion.

[0014] The applicant's German Patent No. 102021210019.8 alleviates this problem by depositing an electrically conductive or protective layer around the defect site, which is electrically conductively connected to a reference structure or drift marker used to correct for drift between the particle beam and the defect site. The conductive protective layer acts as a capacitor. However, the conductive protective layer has the undesirable effect of increasing the amount of charge accumulated over time. This occurs particularly with photomasks that do not have continuous electrically conductive surface structures, such as masks for the ultraviolet (UV) and vacuum ultraviolet (VUV) wavelength ranges. When the electric field associated with the electrostatic charge exceeds a certain limit, the force acting on the particle beam becomes so large that the resulting effects, such as a noticeable change in the beam deflection or field size, are no longer acceptable because the processing and / or analysis of the sample can no longer be performed within the specified specifications of the device.

[0015] On the other hand, EUV masks, i.e., masks for the extreme ultraviolet (EUV) wavelength range, contain flat areas of electrically conductive material, such as metal absorber elements and Bragg mirrors with molybdenum (Mo) layers on a metal cap layer. The resulting charge can be stored delocalized in these connected metal areas, in contrast to the localized accumulation in non-electrically conductive materials, such as the quartz substrate of a transmissive photomask. The EUV mask can then act like a capacitor. The electric field generated by the charge can interfere with imaging and / or processing of the EUV mask with a charged particle beam. This aspect is described in the applicant's application, DE 102019200696.

[0016] Direct electrical contact of the EUV mask, i.e., grounding the EUV mask, is generally problematic as it can damage the photomask. Furthermore, the boundary region structures on the EUV mask are often broken up by what are known as black borders, which means that it is not known a priori where electrical contact will be made.

[0017] The invention is therefore based on the problem of improving known approaches for imaging and / or processing a specimen, in particular when the specimen is in the form of a lithography mask having defects. Summary of the Invention

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

[0019] According to one aspect, a method for setting an electrostatic charge on a specimen includes: (a) adjusting at least one parameter of at least one particle beam such that each particle of the at least one particle beam incident on the specimen ejects, on average, a predetermined average number of electrons from the specimen; (b) irradiating at least one first portion of the specimen with the at least one adjusted particle beam to set the electrostatic charge on the specimen; (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 portion of the specimen; and (d) irradiating at least one second portion of the specimen with the readjusted at least one particle beam and / or the adjusted at least one other particle beam, wherein the at least one first portion and the at least one second portion are separated by a predetermined distance and are electrically conductively connected to each other.

[0020] By setting the electrostatic charge at two different locations or positions on the sample and processing the sample, it is possible to avoid complex overlapping of two particle beams on the sample that differ in at least one parameter. In addition, the spatial separation between charge setting and processing opens up new possibilities for process control. When simultaneously irradiating a first particle beam for setting the charge distribution and a second particle beam for processing a defective sample, one or more parameters of the first and second particle beams can be changed without affecting the location at which they impinge on the sample. Setting the electrostatic charge on the sample has substantially no effect on the analysis and / or processing of the sample. Additionally, the electrostatic charge can be set by the conditioned particle beam such that the conditioned particle beam does not substantially damage the processed sample.

[0021] Furthermore, the method according to the present invention as described above may be carried out with a single particle beam by sequentially setting the electrostatic charge on the sample and analyzing and / or processing the sample. The method according to the present invention is particularly advantageous since it can be used to analyze and / or process electrically conductive samples. In this case, the spatial separation between setting the electrostatic charge and analyzing and / or processing can be carried out without the effort of performing additional process steps.

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

[0023] In this case, there is no need to overlap the two particle beams, which makes it possible to easily implement the described method. 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 of incidence of the particle beam that sets the electrostatic charge of the electrically conductive sample and the particle beam that analyzes and / or processes the sample allows for greater flexibility in the time dimension as well, which makes it possible to use a single particle beam device to analyze or process samples with controlled electrostatic charges at the same time, thereby significantly reducing the complexity of the device for carrying out the method according to the invention.

[0026] The processing particle beam may have a smaller kinetic energy of the particles of the processing particle beam than the analysis particle beam. The electrostatic charge of the (processed) sample may be set separately for both the processing particle beam and the analysis particle beam.

[0027] The analyzing particle beam may image the sample by scanning the sample, in particular the second portion, which may comprise a defective portion or defect of the sample.

[0028] At least one particle beam may irradiate at least one first region according to a first adjustment, at least one second region according to a second adjustment for processing purposes, and at least one second region according to a third adjustment for analysis purposes.

[0029] This means that the particle beam, which sets the electrostatic charge on the sample surface, can be adjusted so that the processing according to the second adjustment of the particle beam and the analysis according to the third adjustment do not exceed a predetermined electrostatic potential.

[0030] It is also possible for at least one particle beam to irradiate at least one first site according to a first adjustment and at least one second site according to a second adjustment to analyze the second site, and for at least one particle beam to irradiate at least one first site according to a third adjustment and at least one second site according to a fourth adjustment to process the second site.

[0031] At least one particle beam may irradiate at least one first region according to a first adjustment, and at least one other particle beam may irradiate at least one second region according to the first adjustment to process the at least one second region, or at least one particle beam may irradiate at least one first region according to a second adjustment, and at least one other particle beam may irradiate at least one second region according to the second adjustment to analyze the at least one second region.

[0032] The predetermined distance may be selected such that illumination of at least one first location separated by the predetermined distance by the at least one particle beam does not substantially affect illumination of at least one second location by the at least one particle beam or at least one other particle beam for analyzing and / or processing at least one second location of the sample.

[0033] This means that the irradiation of the at least one site with the adjusted particle beam has substantially no effect on the execution of adjacent local chemical reactions by the at least one particle beam and / or the at least one other particle beam for processing the defect site or for repairing defects in the sample, which in turn does not affect the setting of a predetermined electrostatic charge in the site to be processed by the irradiation of the at least one site with the adjusted particle beam.

[0034] The predetermined distance may include a minimum distance that must not be exceeded.

[0035] The predetermined distance between the at least one first location and the at least one second location may include at least the length or width of the scan area of ​​the at least one particle beam.

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

[0037] The scanned area of ​​the particle beam may encompass an area of ​​4 μm·4 μm, preferably 8 μm·8 μm, more preferably 12 μm·12 μm, and most preferably 20 μm·20 μm. The predetermined distance may exceed the length or width of the scanned area by 2 times, preferably 10 times, more preferably 100 times, and most preferably 500 times.

[0038] Irradiating the at least one second region to process the at least one second region may include supplying at least one precursor gas to the at least one second region. The at least one second region may include a defect in the sample to be processed. The at least one precursor gas may include at least two members of the group consisting of a deposition gas, an etching gas, or an additive gas. Processing the at least one second region may include initiating a local chemical reaction of the at least one precursor gas with a particle beam and / or another particle beam.

[0039] The concentration of the at least one precursor gas in the at least one first region 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 in the at least one second region being processed.

[0040] The occupation density of the at least one precursor gas at the at least one first site may be less than 50%, preferably less than 10%, more preferably less than 1%, and most preferably less than 0.1% of the maximum occupation density at the second site being processed. The occupation density is defined as the number of precursor gas molecules adsorbed per unit area (e.g., cm 2 (number of winnings).

[0041] The predetermined distance between the at least one first location and the at least one second location 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 invention may further comprise the step of depositing an electrically conductive sacrificial layer at at least one second location of the sample by means of the at least one particle beam and the at least one precursor gas, The deposition of the electrically conductive sacrificial layer may be carried out around at least a part of the location to be machined or around the defect to be machined.

[0043] By depositing an electrically conductive sacrificial layer around at least a portion of the area to be processed, in addition to protecting the sample in the area of ​​the defect area during processing of the defect area, it is possible to set static electricity in the area of ​​the second area to be processed of the electrically insulating sample at a predetermined distance from the area to be processed.

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

[0045] The method according to the present invention may additionally comprise the step of identifying a reference position of the at least one drift marker before starting processing of the at least one defect site.

[0046] The method according to the present invention may further include the steps of interrupting irradiation of the at least one particle beam or the at least one other particle beam to process the at least one second region, identifying a position of the at least one drift marker, identifying a deviation of the identified position of the at least one drift marker from a reference position, correcting a position at which the at least one particle beam or the at least one other particle beam is incident on the at least one second region by the identified deviation, and continuing irradiation with the corrected particle beam to process the at least one second region.

[0047] The interruption of processing and correction of drift of the at least one particle beam may be repeated at regular or irregular time intervals. The repeated processing of the second portion to be processed may be continued until the remaining residual defects in the processed portion are below a predetermined threshold.

[0048] According to a second aspect, a method for setting an electrostatic charge on a specimen includes the steps of: (a) adjusting at least one parameter of at least one particle beam such that each particle of the at least one particle beam incident on the specimen ejects, on average, a predetermined average number of electrons from the specimen; and (b) irradiating the specimen with the at least one adjusted particle beam to set an electrostatic charge on the specimen.

[0049] The method according to the invention does not require direct electrical contact with the sample, thereby avoiding the associated expenses and, in particular, the associated risks. Furthermore, the described method not only allows for the controlled discharge of the electrostatic charge of the sample, but also for the controlled setting of a predetermined electrostatic charge on the sample surface. In addition, the setting, refining, or adjustment of the electrostatic charge does not affect the analysis of the sample, such as the imaging of the sample, and / or the processing of the sample. In addition, accumulated charge may be removed in a controlled manner from non-electrically conductive samples, such as transmission photomasks. The described method also has the advantage that a particle beam already used for the analysis and / or processing of the sample can also be used to set the predetermined electrostatic charge. In addition, the particle beam can also be used to ascertain the size and mathematical sign of the electrostatic charge. Therefore, the expenses for the equipment for carrying out the method according to the invention are low.

[0050] Finally, non-contact electrostatic charge setting may be advantageously used in the repair of lithography masks, i.e., the electrostatic charge on the mask caused by the inspection step may be set to a desired potential or potential level before performing a defect repair process, and after the repair process has been performed, the electrostatic charge on the mask may be determined and set to a level that will not affect a subsequent inspection process to check the success of the repair.

[0051] The electrostatic charge on the sample may be set contactlessly.

[0052] Irradiating the sample may include at least one of focusing at least one particle beam on the sample according to a first adjustment and directing at least one planar particle beam on the sample according to a second adjustment.

[0053] A sample may be analyzed and / or processed using a focused particle beam, also known in the art as a "flood 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. That is, analyzing and processing the sample may generate different electrostatic charges. The alignment of the adjusted particle beam, which spreads over a plane, corresponds to the effect of the flood gun on the site being analyzed or processed. This allows the electrostatic charge of the area inside the inspection or processing area of ​​the sample to be set to a desired potential level.

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

[0055] The dose delivered by the at least one particle beam is determined by the particle flux density, irradiation area, and irradiation time of the particles of the at least one particle beam and / or the particles of the at least one other particle beam incident on the sample. The dose may be delivered in a single irradiation operation to the site of the sample over a time interval determined by the dose. The treatment dose may also be delivered in part by periodic irradiation. The at least one particle beam may be scanned over an area of ​​the sample to deliver a predetermined dose to the area of ​​the sample. The beam spot of the at least one particle beam may be adapted to the area of ​​the sample to be irradiated.

[0056] A particle beam with sufficient energy to eject electrons from a sample can electrostatically charge a sample, especially a non-electrically conductive or ungrounded sample. If the beam incident on the sample, hereinafter referred to as the primary beam, contains electrically neutral particles such as photons and / or atoms, an electrically insulating sample always acquires a positive electrostatic charge. Because the primary beam should not have a detrimental effect on the sample during inspection and / or processing, i.e., because sputtering effects are undesirable, the photons and / or atoms of the primary beam produce primarily free electrons in the sample. Some of these electrons can leave the sample as secondary particles. Secondary particles include photons of various wavelengths as well as secondary electrons (SEs) and / or backscattered electrons (BSEs), which are used, among other things, to detect the electrostatic charge of a sample. SEs and BSEs leaving the sample result in an excess positive charge in a sample irradiated with an electrically neutral primary beam. This can be reduced or compensated for, for example, by irradiating with an electron beam in which the electrons have a corresponding incident energy.

[0057] Primary beams containing electrically neutral or positively charged particles will produce SEs but not BSEs. BSEs usually only occur when the primary beam contains electrons. This should be taken into consideration when referring below to the emission of SEs and BSEs by particle beams.

[0058] When a sample is irradiated with a primary beam containing (positively charged) ions, the charge balance is also positive. The ions in the primary beam cause the primary beam to impart a positive charge to the sample, and the BSE and SE further remove the negative charge from the sample, resulting in the sample taking on a positive electrostatic charge. The excess positive charge can be set, for example, by irradiating the sample with electrons having a suitably adjusted incident energy.

[0059] When negatively charged particles such as electrons are used in the primary beam, the charge balance at the sample can be positive, negative, or neutral, depending on whether, on average, more than one secondary electron (the sum of BSE and SE) can leave the sample per negatively charged particle in the primary beam that is incident on the sample, or whether less than one secondary electron can leave the sample.

[0060] The charge balance of a sample when irradiated with a massive particle beam depends on the incident energy of the particles. When the incident energy is very small, the massive particles of the primary beam will, on average, release less than one secondary particle (BSE and SE) per incident primary particle, resulting in a low electrostatic charge on the sample. The mathematical sign of the electrostatic charge on the sample is determined by the charge of the particles in the primary beam. As the incident energy increases, the number of SEs and BSEs that can leave the sample increases, which in turn increases the electrostatic charge on the sample. As explained above, depending on the charge of the particles in the primary beam, the mathematical sign of the electrostatic charge on the sample can be reversed.

[0061] For electrons, which are often used as the primary beam, at low incident energies the charge balance is negative, and the sample carries a negative electrostatic charge. Over the average incident energy range, one electron from the primary beam produces, on average, a total of one or more SEs and BSEs, and the sample carries a positive electrostatic charge. At higher incident energies of the primary beam electrons, the rate of SE and BSE generation decreases again, and the charge balance is dominated by the charge introduced to the sample by the primary beam electrons.

[0062] At least one parameter of at least one particle beam and / or at least one parameter of at least one other particle beam may depend on the material composition of the irradiated area of ​​the sample and / or the surface shape of the irradiated area of ​​the sample. On the one hand, the atomic number or material composition of the material of the sample to be analyzed or processed influences the SE and / or BSE generation rate of the primary beam. On the other hand, edges and / or sharp edges of the surface increase the SE generation rate of the primary beam, especially locally. The SE yield of a sample or solid is determined by the electrical structure of the sample or solid, the energy positions of the valence and conduction bands, the Fermi level, and the discharge work that the SEs must overcome on the surface.

[0063] When photons are used as the primary beam, there is a threshold wavelength of photons above which the photons can release electrons from their bonds in the sample. As the wavelength shortens, i.e., the energy increases, the photon electron emission rate, i.e., the photon SE generation rate or photon yield, increases. The SE generation rate also depends on the flux density of the primary beam incident on the sample when the photons have a wavelength shorter than the threshold wavelength. This means that the higher the beam intensity of the photon beam (above the energy threshold), the larger the SE beam that emerges from the sample.

[0064] The adjustment of the at least one parameter of the at least one particle beam may comprise at least one element from the group of: setting a fixed numerical value, setting a range of values ​​through which the at least one parameter passes at least once during irradiation of the sample, and shifting the range of values.

[0065] The at least one parameter may be traversed linearly or non-linearly through a range of values. Further, the at least one parameter of the at least one particle beam may be oscillated within a range of values. The amplitude of the oscillation may be constant or may vary within a predetermined range of values.

[0066] By setting a range of values ​​for at least one parameter, it is possible to experimentally determine the optimum value for at least one parameter. This procedure can be advantageous when the material composition and / or geometry of the sample are unknown or not known in detail. This procedure can also be advantageous when the effect of the particle beam on the sample is not fully understood.

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

[0068] In addition to the incident energy, the current intensity or flux density of at least one particle beam determines the charge q(t) produced by the particle beam on the sample per unit time. The charge accumulated on the sample over the irradiation time t-t gives the electrostatic charge:

[0069]

number

[0070] The sample may be electrostatically charged positively / negatively by irradiating the at least one particle beam according to a first adjustment of at least one parameter, and may be electrostatically charged negatively / positively by irradiating the at least one particle beam according to a second adjustment of at least one parameter.

[0071] For example, a sample may be analyzed or imaged with a primary beam of greater incident energy to enhance the lateral spatial resolution of the particle beam used. When the primary beam uses electrons and the sample being analyzed includes a photomask, electron incident energies greater than 2 keV, such as 2 keV-5 keV, 2 keV-4 keV, 2.5 keV-3.5 keV, or kinetic energies of approximately 3 keV, can be used in the imaging process. To optimize the lateral spatial resolution of localized particle beam-induced chemical reactions, electron incident energies in the ranges of 20 eV-2500 eV, 40 eV-2000 eV, 70 eV-1500 eV, 100 eV-1100 eV, 150 eV-800 eV, and 200 eV-600 eV can be used in the repair process.

[0072] Analysis and / or processing of a sample with at least one particle beam may result in different electrostatic charges because both processes may use different incident energies of particles in the primary beam. The electrostatic charge of the sample may be set according to adjustment of at least one parameter of the at least one particle beam before or after the sample is imaged that is different from adjustment of at least one parameter of the at least one particle beam to set the electrostatic charge after a processing process is performed.

[0073] Irradiating the sample according to the second adjustment of the at least one parameter of the at least one particle beam may substantially compensate for electrostatic charges on the sample caused by irradiating the sample according to the first adjustment of the at least one parameter of the at least one particle beam.

[0074] In the special case of setting electrostatic charges, a second adjustment of the at least one particle beam may be adjusted such that the electrostatic charge of the sample caused by the first adjustment of the at least one parameter is compensated for by irradiating the sample according to the second adjustment of the at least one parameter.

[0075] The term "substantially" here, as elsewhere in this application, means that the reading of the measured quantity is within customary error limits when conventional metrology is used to measure the quantity.

[0076] The at least one particle beam may comprise particles from the group of electrons, ions, atoms, molecules, and high-energy photons. Currently, electrons are preferably used for both sample analysis and sample processing. Electrons currently offer the best possible compromise between accurate imaging and processing of the sample on the one hand and damage to the sample caused by electron bombardment on the other hand.

[0077] High energy photon sources have the advantage that they are not affected by static charges on the sample.

[0078] The particle beam may include electrons, and at least one parameter of the at least one particle beam may include the incident energy of the electrons at the sample. The incident energy of the electrons, or generally of electrically charged particles, may be set by selecting an acceleration voltage for the charged particles and / or by applying a braking voltage directly 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 attached to the column output of the particle-optical column, which metal tube is technically referred to as a "liner tube." If a screening grid is attached to the column output of the scanning particle microscope, the braking voltage for the charged particles may be set by applying a corresponding potential between the screening grid and the metal tube.

[0079] High-energy photons can have sufficient energy to liberate electrons from their bonds in the material of the sample when the photons are absorbed by the sample. Photons from the VUV wavelength region, and particularly the EUV wavelength region, of the electromagnetic spectrum have sufficient energy to liberate electrons.

[0080] The method according to the invention may further comprise the step of supplying at least one precursor gas to the processing site of the sample while irradiating the sample with the at least one tailored particle beam.

[0081] Defects in the specimen may be repaired by particle-beam-induced local chemical reactions using at least one precursor gas. In the case of material-missing defects (bright defects), at least one precursor gas in the form of a deposition gas may be supplied to the location of the defect. In the case of material-excess defects (dark defects), at least one precursor gas in the form of an etching gas may be supplied to the location of the defect. The at least one precursor gas may include at least one additive gas in addition to at least one etching gas and / or at least one deposition gas.

[0082] The at least one deposition gas may comprise at least one member of the group of 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.

[0083] The metal alkyls, transition element alkyls, and main group alkyls may include at least one member from the group consisting of cyclopentadienyl (Cp)trimethylplatinum (CpPtMe3), methylcyclopentadienyl (MeCp)trimethylplatinum (MeCpPtMe3), tetramethyltin (SnMe4), trimethylgallium (GaMe3), ferrocene (Cp2Fe), and bisarylchromium (Ar2Cr). The metal carbonyls, transition element carbonyls, and main group carbonyls include chromium hexacarbonyl (Cr(CO)6), molybdenum hexacarbonyl (Mo(CO)6), tungsten hexacarbonyl (W(CO)6), dicobalt octacarbonyl (Co2(CO)8), triruthenium dodecacarbonyl (Ru3(CO) 12 The metal alkoxides, transition element alkoxides, and main group alkoxides may include at least one element from the group of tungsten hexafluoride (WF), tungsten hexachloride (WC16), titanium hexachloride (TiCl), boron trichloride (BC13), and silicon tetrachloride (SiCl4). The metal alkoxides, transition element alkoxides, and main group alkoxides may include at least one element from the group of tetraethyl orthosilicate (TEOS, Si(OC2H5)4) and tetraisopropoxytitanium (Ti(OC3H7)4). The metal halides, transition element halides, and main group halides may include at least one element from the group of tungsten hexafluoride (WF6), tungsten hexachloride (WC16), titanium hexachloride (TiCl6), boron trichloride (BC13), and silicon tetrachloride (SiCl4). The metal complexes, transition element complexes, and main group complexes may include at least one member of the group of copper bis(hexafluoroacetylacetonate) (Cu(CFHO)) and dimethyl gold trifluoroacetylacetonate (MeAu(CFHO)). The organic compounds may include at least one member of the group of carbon monoxide (CO), carbon dioxide (CO), aliphatic hydrocarbons, aromatic hydrocarbons, components of vacuum pump oil, and volatile organic compounds.

[0084] The at least one etching gas may include one element from the group consisting of a halogen-containing compound and an oxygen-containing compound. The halogen-containing compound may include at least one element from the group consisting of fluorine (F), chlorine (Cl), bromine (Br), iodine (I), xenon difluoride (XeF), dixenon tetrafluoride (XeF), hydrofluoric acid (HF), hydrogen iodide (HI), hydrogen bromide (HBr), nitrosyl chloride (NOCl), phosphorus trichloride (PCl), phosphorus pentachloride (PCl), and phosphorus trifluoride (PF). The oxygen-containing compound may include at least one element from the group consisting of oxygen (O), ozone (O), water vapor (HO), hydrogen peroxide (HO), nitrous oxide (NO), nitrogen dioxide (NO), and nitric acid (HNO).

[0085] The at least one additive gas may comprise at least one member of the group of an oxidizer, a halide, and a reducing agent.

[0086] The oxidizing agent may include at least one element from the group consisting of oxygen (O), ozone (O), water vapor (H), hydrogen peroxide (H), nitrous oxide (N), nitrogen dioxide (N), and nitric acid (HNO). The halide may include at least one element from the group consisting of chlorine (Cl), hydrochloric acid (HCl), xenon difluoride (XeF), hydrofluoric acid (HF), iodine (I), hydrogen iodide (HI), bromine (Br), hydrogen bromide (HBr), nitrosyl chloride (NOCl), phosphorus trichloride (PCl), phosphorus pentachloride (PCl), and phosphorus trifluoride (PF). The reducing agent may include at least one element from the group consisting of hydrogen (H), ammonia (NH), and methane (CH).

[0087] An electrically conductive sacrificial layer may be deposited by supplying a precursor gas Mo(CO)6 and an additive gas NO2. The sacrificial layer thus deposited may be removed by mask cleaning.

[0088] The electrically conductive sacrificial layer allows for the spatial separation of the electrostatic charge setting from the analysis or processing of the sample. Additionally, setting the electrostatic charge on the sample through the electrically conductive sacrificial layer minimizes sample damage caused by irradiation of the sample.

[0089] The lateral extent of the localized particle beam-induced chemical reaction for depositing material and for locally removing material from a sample may be in the range of less than 10 nm, preferably less than 7 nm, and most preferably less than 5 nm. The edge placement error of pattern elements of a lithography mask should be less than 2.1 nm, preferably less than 1.4 nm, and most preferably less than 1.0 nm when the pattern elements are measured and / or after they have been repaired. The placement of pattern elements of a lithography mask can be measured with a repeatability of 0.5 nm or better. The placement accuracy is in the range of 1 nm or better.

[0090] The at least one particle beam may include at least one first particle beam and at least one second particle beam.

[0091] The method according to the invention may further comprise the steps of analyzing and / or processing the sample by means of at least one adjusted second particle beam and setting an electrostatic charge on the sample by means of at least one adjusted first particle beam.

[0092] The described method may additionally include imaging the sample with at least one first particle beam according to a first adjustment, setting an electromagnetic charge of the sample by at least one second particle beam according to the first adjustment, processing the sample with the at least one first particle beam according to the second adjustment, and setting an electromagnetic charge of the sample by at least one second particle beam according to the second adjustment.

[0093] The at least one first particle beam may comprise a tailored focused particle beam used to image and / or process 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 performed by the particle beam. For example, analysis of the sample may be performed by charged particles of a particle beam with a higher incident energy than processing of 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, it is also possible for the at least one first particle beam and the at least one second particle beam to use particles whose charges have different mathematical signs. For example, the at least one first particle beam may use electrons and the flood gun may use (positively charged) ions, or vice versa.

[0094] The method according to the present invention may further comprise the steps of focusing the at least one first particle beam on the sample according to a first adjustment of the at least one parameter, and irradiating the at least one second particle beam onto a flat area on the sample according to a second adjustment of the at least one parameter.

[0095] The method according to the present invention may additionally comprise the step of scanning the at least one first focused particle beam in accordance with the first adjustment of the at least one parameter over an area of ​​the sample that is irradiated with the at least one second particle beam in accordance with the second adjustment of the at least one parameter.

[0096] The at least one first particle beam and the at least one second particle beam may use the same type of particles, such as electrons. However, it is also possible for the at least one first particle beam and the at least one second particle beam to use different types of particles. For example, the at least one first particle beam may include photons and the at least one second particle beam may include electrons.

[0097] The method according to the present invention may further include simultaneously irradiating the sample with at least one first particle beam according to a first adjustment of at least one parameter and at least one second particle beam according to a second adjustment of at least one parameter. The second adjustment of the at least one second particle beam may be adjusted relative 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 include electrons, and the combination of the first adjustment of at least one parameter of the at least one first particle beam and the second adjustment of at least one parameter of the at least one second particle beam can result in a yield of 1, i.e., a particle of the first particle beam and a particle of the second particle beam emits, on average, two electrons from the sample. Irradiating the sample with two or more electron beams adjusted in this manner does not change the electrostatic charge of the sample.

[0098] The method according to the present invention may additionally comprise the step of electrically connecting a second portion of the sample to be analyzed and / or processed to at least one first portion of the sample, the second portion to be analyzed and / or processed and the at least one first portion being separated from each other by a predetermined distance.

[0099] Electrically 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 anywhere on the sample. In particular, the at least one first site may be selected at a location on the sample where particle irradiation does not affect the function of the sample.

[0100] An electrically conductive connection between the second portion to be analyzed and / or processed and the at least one first portion may be created by depositing a conductive layer on the sample using at least one precursor gas including at least one tuned particle beam and at least one deposition gas.

[0101] At least one portion of the sample to be analyzed and / or processed may be irradiated with at least one conditioned second particle beam, and at least one first portion of the sample may be irradiated with at least one conditioned second particle beam.

[0102] The method according to the present invention may include simultaneously irradiating a second portion of the sample to be analyzed and / or processed and at least one first portion of the sample. The at least one adjusted second particle beam may irradiate the second portion of the sample to be analyzed or processed, and the at least one adjusted first particle beam may simultaneously irradiate the at least one first portion of the sample. In this embodiment, it is possible to ensure that the sample has a predetermined electrostatic charge during inspection and / or during the sample processing process. In particular, by adjusting the at least two particle beams relative to each other, it is possible to inspect or process the sample such that the sample has substantially no electrostatic charge. If at least one parameter of the at least one second particle beam is adapted during the transition from the analysis process to the processing process, a change in the at least one parameter of the at least one second particle beam can be compensated for by adapting a corresponding parameter of the at least one parameter of the at least one first particle beam.

[0103] The electrostatic charge of the sample to be compensated may encompass a voltage range of -5000V to +5000V, -1000V to +1000V, -200V to +200V, or -50V to +50V.

[0104] The tuned particle beam may be used to set the electrostatic charge on the sample encompassing voltage ranges of -3000V to +3000V, -1000V to +1000V, or -500V to +500V.

[0105] When the primary beam comprises an electron beam, the electrons of the electron beam for setting the static charge may have an incident energy in the range of 10V to 5000V, preferably 20V to 4000V, more preferably 30V to 3000V, and most preferably 50V to 2000V.

[0106] The specimen may include an element from the group of a lithography mask, a stamp mold for nanoimprint lithography, a wafer, an integrated circuit (IC), a micro-electromechanical system (MEMS), a nano-electromechanical system (NEMS), and a photonic integrated circuit (PIC). The lithography mask may include a transmissive or reflective photomask. The mask may also include any type of mask.

[0107] The specimen may include at least one defect having an electrically conductive protective layer disposed around at least a portion thereof, and the at least one tuned second particle beam may irradiate the at least one defect, and the at least one tuned first particle beam may irradiate the electrically conductive protective layer. The specimen may include a lithography mask. The at least one defect may include a missing material defect and / or a surplus material defect.

[0108] The at least one particle beam may analyze and / or process the at least one defect according to a first adjustment of the at least one parameter, and may irradiate the electrically conductive protective layer according to a second adjustment of the at least one parameter to set a predetermined electrostatic charge in the region of the at least one defect of the specimen.

[0109] The sample may be provided with two or more drift markers that are not arranged in a straight line and therefore span a two-dimensional (2D) coordinate system. By displacing at least three drift markers relative to a reference position before the start of the analysis and / or processing process, it is possible to ascertain distortions of the imaging scale or changes in size in the 2D coordinate system caused by electrostatic charging of the sample surface.

[0110] The method according to the present invention may further comprise the step of reducing the electrostatic charge of the specimen by increasing the surface area of ​​the electrically conductive protective layer. The capacitance of a capacitor is proportional to the surface area of ​​the capacitor that can store charge. Increasing the surface area of ​​the electrically conductive protective layer makes it possible to reduce the increase or degree of electrostatic charge caused by irradiation with a particle beam that can release electrons from the electron bonds of the protective layer. A lower surface area charge density results in a lower strength of the electrostatic field that is generated, which in turn results in a smaller deflection of the charged particle beam.

[0111] The method according to the present invention may further comprise a step of determining the electrostatic charge of the sample by at least one of the following factors: a change in size of at least one reference structure of the sample, or a drift correction of the at least one adjusted particle beam during analysis and / or processing of the sample.

[0112] When the sample is charged with an electrostatic charge, a change in the imaging scale occurs. At least one reference structure of the sample can be imaged larger or smaller by the charged particle beam depending on the type of charge. 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 charge of the sample can be determined from the measured change in size of the at least one reference structure.

[0113] A reference element in the form of a drift marker is used to measure and correct drift between the second portion of the sample being analyzed or processed and the particle beam during the analysis or processing process. If two or more drift markers are used for this purpose around the second portion of the sample being analyzed or processed, size changes or distortions in the imaging scale can be determined from changes in the positions 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 ascertain the size and mathematical sign of the electrostatic charge on the sample.

[0114] The method according to the present invention may further include the steps of analyzing at least one defect using at least one adjusted particle beam, processing a majority of the defect using at least one particle beam, and processing the remaining resident defects using at least one adjusted particle beam. This means that the remaining defects, including in particular the defect boundaries, are analyzed and processed without the influence of electrostatic charges on the sample, while no attention is paid to electrostatic charges on the sample surface during processing of the majority of the defect. This process control allows for faster defect repair without compromising the accuracy of the defect repair.

[0115] The method according to the present invention may further comprise, prior to processing and / or analyzing the sample, in particular at least one defect of the sample, a step of electrostatically charging the sample within a predetermined potential interval by irradiating the sample with at least one particle beam according to a first adjustment. The sample is then analyzed and / or processed according to a second adjustment of at least one parameter of the at least one particle beam. By irradiating the sample according to the second adjustment of the at least one parameter, the sample acquires an electrostatic charge of an opposite mathematical sign to the electrostatic charge of the sample resulting from irradiating the sample according to the first adjustment of the at least one parameter of the at least one particle beam. The potential interval may comprise an electrical potential interval. The electrical potential interval may comprise a voltage.

[0116] The method defined in this application opens up the possibility of charging a sample in a defined and controlled manner to a voltage level that does not interfere with subsequent analysis and / or subsequent processing by irradiation with a charged particle beam. This means that deflection of the charged particle beam remains below a tolerable threshold. By selecting the mathematical sign of the controlled electrostatic charge, it is possible to double the processing time before the electrostatic charge of the sample arising in the processing process has a significant effect on the analysis or processing process.

[0117] A computer program stored in the non-volatile memory may include instructions that cause a computer system to perform the method steps of one of the aspects described above.

[0118] According to a further aspect, a device for setting an electrostatic charge on a specimen comprises: (a) means for adjusting at least one parameter of at least one particle beam such that each particle of the at least one particle beam incident on the specimen emits, on average, a predetermined average number of electrons from the specimen; (b) means for irradiating at least one first portion of the specimen with the at least one adjusted particle beam to set the electrostatic charge on the specimen; (c) means for readjusting at least one other particle beam to analyze and / or process at least one second portion of the specimen; and (d) means for irradiating at least one second portion of the specimen with the readjusted at least one particle beam and / or the adjusted at least one other particle beam, wherein the at least one first portion and the at least one second portion are separated by (at least) a predetermined distance and are electrically conductively connected to each other.

[0119] According to another aspect, a device for setting an electrostatic charge on a specimen comprises: (a) means for adjusting at least one parameter of at least one particle beam such that each particle of the at least one particle beam incident on the specimen ejects, on average, a predetermined average number of electrons from the specimen; and (b) means for irradiating the specimen with the at least one adjusted particle beam to set the electrostatic charge on the specimen.

[0120] The device may be configured to perform the method steps of the aspects described above.

[0121] The means for adjusting at least one parameter of the at least one particle beam and / or at least one parameter of the at least one other particle beam may comprise at least one element of the group of: means for setting an acceleration voltage of particles of the at least one particle beam and / or of particles of the at least one other particle beam, means for setting a braking voltage of particles of the at least one particle beam and / or of particles of the at least one other particle beam, means for setting a wavelength of particles of the at least one particle beam and / or of particles of the at least one other particle beam, means for setting a flux density of the at least one particle beam and / or of the at least one other particle beam or means for setting an irradiation time of particles of the at least one particle beam and / or of particles of the at least one other particle beam.

[0122] The means for setting the acceleration voltage may include setting an anode potential and / or a cathode potential of a particle source for charged particles. The means for setting the braking voltage may include setting a potential of a metal tube at the output of a particle-optical column of the scanning particle microscope. The means for setting the braking voltage may additionally include setting a potential between a shield grid attached to the column output and a metal tube (liner tube). The means for setting the wavelength of particles of the at least one particle beam may include a broadband light source (for the VUV wavelength range and / or the EUV wavelength range) and one or more bandpass filters. The means for setting the wavelength may further include a first light source emitting light in a first wavelength range and at least one second light source emitting light in at least one second wavelength range different from the first wavelength range. The means for setting the fluence density of the at least one particle beam may include setting the beam intensity and / or one or more absorption filters of the particle source when the particle source includes a photon source. The means for setting the exposure time may include a beam blanker.

[0123] The device according to the invention may further comprise at least one element from the group of an electron flood gun, an ion flood gun, an adjustable aperture for the at least one particle beam, at least one second particle beam source for generating the at least one second particle beam, or an energy selective detector for secondary electrons and / or backscattered electrons.

[0124] The flood gun may contain charged particles having the same mathematical sign as the particles in the primary beam. The particles from the flood gun may be oppositely charged to the particles in the primary particle beam. The adjustable aperture may include a condenser aperture of a particle-optical column of a scanning particle microscope. The opening 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 include an aperture system consisting of two or more apertures. The aperture or aperture system may be located after (downstream from) the condenser of the particle-optical column of the scanning particle microscope. The second particle beam source allows for processing the sample with a second particle beam from the second particle beam source and simultaneously setting a predetermined electrostatic charge on the sample by irradiating at least one first location with a first particle beam from at least one first particle beam source.

[0125] An energy-selective detector may comprise a spectrometer-detector combination with a filter or filter system that discriminates between SEs and BSEs according to energy. For example, a retarding field spectrometer, a deflection spectrometer using magnetic or electrostatic fields, e.g., in the form of a cylindrical deflection analyzer (CDA), may be used as a spectrometer or energy filter. It is also possible to use a multi-channel spectrometer that can simultaneously identify substantially the entire energy spectrum of SEs and / or BSEs.

[0126] The device according to the invention may further comprise means for moving the point of incidence of the at least one particle beam from at least one first location on the sample to at least one second location on the sample to be processed.

[0127] The device according to the invention can comprise at least one particle beam in the form of at least one electron beam, the incident energy of which can be set so that the cumulative SE and BSE generation rate (in the case of an electron beam, per electron of the primary electron beam) is less than 1. This applies when the incident energy is less than a first energy threshold E1 and greater than a second energy threshold E2. When a sample is irradiated with electron incident energies in these ranges, the sample acquires a negative electrostatic charge. As already explained above, the lowest possible incident energy of the electrons of the electron beam, i.e., in the energy range below E1, is advantageous for carrying out processing processes on lithography masks.

[0128] Within the energy interval E1-E2, the sum of the yields of SE(δ) and BSE(η) is greater than 1, and the sample acquires a positive electrostatic charge. The faster the electrostatic charging is carried out, the greater the deviation of the sum of the yields from 1. If the incident energy of the charged particles can be freely selected within a certain interval, it is advantageous to select the sum of δ and η as close to 1 as possible. Conversely, if it is intended to electrostatically charge the sample in a controlled manner, it is advantageous to select the yields of SE and BSE as far from 1 as possible for this purpose.

[0129] Thus, at least one parameter may be optimized for various purposes. For example, when imaging a sample, it may be useful to scan the sample with the highest possible lateral resolution, which typically requires a larger incident energy. This results in SE and BSE yields in the range of more than 1.5. On the other hand, when processing a sample, it may be advantageous to select the lowest possible incident energy of the primary electrons to minimize the lateral spread of chemical reactions induced by the electron beam. For this electron incident energy, the yields typically fall within the range of 0.5 or less. The different electrostatic charges on the sample can be set to desired levels by irradiating the sample within the incident energy interval E1-E2 according to a second adjustment of at least one parameter of at least one electron beam. Alternatively and / or additionally, the sample may be irradiated with a low-energy ion beam in which the SE and BSI yields are less than 1, where BSI stands for backscattered ions. BSI occurs particularly with ions with low atomic numbers, while ions with large or high atomic numbers are predominantly implanted in the sample.

[0130] The devices described herein may further comprise a gas supply system capable of supplying one or more precursor gases to a sample processing location, the gas supply system being capable of setting the gas flow rate, partial pressure, and temperature of the one or more precursor gases.

[0131] The device according to the invention may further comprise means for directing the at least one particle beam towards the sample. The device may further comprise means for receiving information regarding at least one parameter of the at least one particle beam. The device may further comprise means for confirming at least one adjustment of the at least one parameter of the at least one particle beam. The device may further comprise means for adjusting the at least one parameter of the at least one particle beam.

[0132] The means for receiving information may comprise a user interface. For example, it may be possible for a user of the device to provide information regarding at least one parameter of at least one particle beam by means of software, hardware, or a combination thereof. The device may then automatically adjust the at least one parameter accordingly using an identifying means (e.g., a computer unit, a processor, etc.). A semi-automatic selection is also conceivable, in which the device presents the user with a choice of adjustment options for at least one parameter of at least one particle beam and / or at least one other particle beam, the adjustment option being adapted to the respective process and / or sample to be processed and ultimately selectable by the user.

[0133] A user of the device can use a user interface to provide data regarding the material composition and / or surface topography of the specimen. The device may take this data into account when determining the at least one parameter. The device may further be designed to take the specimen data into account when outputting adjustment options to the user.

[0134] The device according to the invention may further comprise means for performing a repair form at the at least one second location by means of at least one other particle beam, which means may further be configured to irradiate the at least one first location with the at least one particle beam in order to set an electrostatic charge on the sample.

[0135] The device may further comprise a database storing the material compositions and surface topographies of various specimens. The specimens may have a code that stores the specimen type along with associated material and surface data. The device can read the specimen code and ascertain from the defect data the optimal adjustment option for at least one parameter.

[0136] The device may be designed such that the means for receiving information is adapted to receive information identifying the first process as a diagnostic process and / or the second process as a repair process.

[0137] Also, a device for setting the electrostatic charge of a specimen may be provided that does not comprise means for directing a particle beam to a mask. This may be provided as a separate hardware device, for example intended to interact with an apparatus for directing a particle beam to a specimen, for example via a (software) interface for providing information about at least one parameter of at least one particle beam and / or about the first and / or second process. In addition to or as an alternative to a device for this purpose, a corresponding computer program may also be provided.

[0138] The devices described herein may be configured as a whole to perform the methods described herein, and conversely, all aspects described herein with respect to devices may also be implemented as method steps.

[0139] In the following detailed description, presently preferred exemplary embodiments of the invention are described with reference to the following drawings: [Brief explanation of the drawings]

[0140] [Figure 1A] 1A and 1B are schematic diagrams illustrating the irradiation of an electron beam onto a lithography mask that does not carry an electrostatic charge, the mask comprising a reference structure and a defect with four drift markers; [Figure 1B] 1A and 1B are schematic diagrams illustrating the irradiation of an electron beam onto a lithography mask that does not carry an electrostatic charge, the mask comprising a reference structure and a defect with four drift markers; [Figure 1C] 1A and 1B are schematic diagrams illustrating the irradiation of an electron beam onto a lithography mask that does not carry an electrostatic charge, the mask comprising a reference structure and a defect with four drift markers; [Figure 2A]1A-1C, where the mask has a positive electrostatic charge. [Figure 2B] 1A-1C, where the mask has a positive electrostatic charge. [Figure 2C] 1A-1C, where the mask has a positive electrostatic charge. [Figure 3A] 1A-1C, where the mask has a negative electrostatic charge. FIG. [Figure 3B] 1A-1C, where the mask has a negative electrostatic charge. FIG. [Figure 3C] 1A-1C, where the mask has a negative electrostatic charge. FIG. [Figure 4] FIG. 1 is a diagram illustrating a schematic example of the current when an electrically conductive sample (left) and an electrically insulating sample (right) are irradiated with a particle beam. [Figure 5] FIG. 1 shows a schematic diagram of the sum of the secondary electron (SE) yield δ and the backscattered electron (BSE) yield η as a function of particle energy of the primary beam. [Figure 6] 1A-1C are schematic reproductions of the imaging process of an EUV mask using an electron beam and the fabrication process of an EUV mask using an electron beam and a precursor gas. [Figure 7] 7 is a diagram illustrating a schematic configuration of the electrostatic charge of the EUV mask of FIG. 6; [Figure 8] FIG. 8 is a schematic representation of the imaging / processing and electrostatic charge setting of the EUV mask of FIGS. 6 and 7 performed simultaneously using two electron beams. [Figure 9] FIG. 8 schematically repeats the setting of electrostatic charge on the EUV mask of FIG. 7, in which the EUV mask comprises an electrically conductive sacrificial layer that is irradiated to set the electrostatic charge. [Figure 10]FIG. 10 shows a schematic diagram of setting an electrostatic charge on a transmissive mask, the transmissive mask comprising an electrically conductive sacrificial layer on which reference structures in the form of drift markers are present, the sacrificial layer being irradiated to set the electrostatic charge. [Figure 11] FIG. 10 is a schematic re-reproduction of the transmission mask of FIG. 9, in which a first electron beam analyzes or processes the mask and a second electron beam sets up an electrostatic charge on the mask. [Figure 12] The upper partial image shows a schematic representation of the time profile of the electrostatic charge on the sample, and the lower partial image shows a schematic illustration of the possible charges with a given polarity. [Figure 13] 1 is a schematic cross-section through a device according to the invention; [Figure 14] 1 is a flow diagram of a method according to the present invention; [Figure 15] 4 is a flow diagram of another method according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0141] Presently preferred embodiments of the method according to the invention and the device according to the invention for setting the electrostatic charge of a specimen are described in more detail below with reference to the examples of a lithography mask and a modified scanning electron microscope. However, the method according to the invention is not limited to the reflective and transmissive photomasks described below. On the contrary, the method according to the invention may be used to set the electrostatic charge of any microstructure specimen, such as stamp molds for nanoimprint lithography, wafers, ICs, MEMS, NEMS, and PICs. Furthermore, the device according to the invention is not limited to the examples described below. As those skilled in the art will readily recognize, any scanning particle microscope, for example, using a focused ion beam and / or a focused photon beam as an energy source, can be used instead of the modified scanning electron microscope under consideration.

[0142] Presently preferred embodiments of the invention are described in more detail below with reference to the drawings.

[0143] 1A-1C illustrate an exemplary lithography mask 100 (hereafter simply mask 100) comprising a reference structure 130, a defect 150, and four reference elements 160, according to one example.

[0144] 1A shows a cross-sectional view through a mask 100 whose surface 105 carries a pattern 110. The surface 105 or pattern 110 is illuminated by an electron beam 120. The electron beam 120, which is an example of a particle beam 120, is focused on the surface 105 of the mask 100 and scans the surface 105 of the mask 100 to acquire an image of the mask pattern 110. The incident energy of the electrons 125 of the electron beam 120 is typically selected to minimize the focused spot of the electron beam 120 on the mask 100, thereby achieving maximum lateral resolution. For this purpose, electron incident energies of around 3 keV are typically used.

[0145] However, it is also possible to acquire an image of a sample, such as mask 100, with the incident energy of electron beam 120 used to fabricate mask 100. This procedure eliminates the need to realign particle beam 120 or electron beam 120 when transitioning from the analysis process to the fabrication process. Additionally, for the purpose of imaging a sample, electron beam 120 may be scanned multiple times over the same region of the sample with different incident energies of electrons 125 to improve imaging quality.

[0146] FIG. 1B presents a schematic diagram of a reference structure 130 of the mask 100. The exemplary reference structure 130 of FIG. 1B is a square divided into nine partial squares 140 by lines 135. The reference structures 130 may be arranged to be distributed at regular or irregular intervals across the mask 100. The reference structures 130 may be used to determine electrostatic charges on the mask 100, or on the sample 100 in general, as described below. In principle, both the position and size of the reference structures 130 are known by the manufacturer of the mask 100. If this is not the case, the position and size of the reference structures 130 may be determined, for example, using a mask inspection tool.

[0147] FIG. 1C illustrates a schematic diagram of a defect 150 in the mask 100. The exemplary defect 150 is a material-excess defect, i.e., a dark defect 150. Of course, the method described herein may also be used for precise imaging and / or repair of a material-deficient defect, i.e., a bright defect 150. In FIG. 1C, four reference elements 160 in the form of drift markers 160 are deposited around the defect 150. The drift markers 160 may be deposited around the defect 150 in the mask 100 using an electron beam induced deposition process while supplying at least one precursor gas in the form of a deposition gas. The drift markers 160 span a two-dimensional (2D) coordinate system. Three non-linearly arranged reference elements 160 are sufficient to span the 2D coordinate system. The drift marker 160 is periodically scanned by the electron beam 120 primarily to detect drift of the defect 150 or drift of the drift marker 160 relative to a reference position of the drift marker 160 during the repair process of the defect 150. The change in the position of the drift marker 160 relative to the reference position of the drift marker 160 may also be used to check the electrostatic charge on the mask 100 in addition to identifying the relative drift between the electron beam 120 and the drift marker 160 or the defect 150 on the mask 100.

[0148] During the repair of the defect 150, when the electron beam 120 scans the defect 150 in the mask 100, it is advantageous to select the incident energy of the electrons 125 at the defect 150 as small as possible in order to minimize the diameter of the local chemical reaction induced by the electron beam 120. For this purpose, an electron incident energy of 600 eV, preferably 400 eV, and most preferably 300 eV or less is advantageous. For imaging the drift marker 160, it may be advantageous to use an electron incident energy that is also used for repairing the defect, i.e., an electron incident energy in the range of 600 eV, preferably 400 eV, and most preferably 300 eV or less. In addition, it may be advantageous to perform imaging of the drift marker (see FIG. 11 below) with electrons 125 of the electron beam 120 having an incident energy in the range above 600 eV, for example, 3 keV.

[0149] 2A-2C repeat the illustrations of FIGS. 1A-1C. However, unlike FIGS. 1A-1C, the mask 100 in FIGS. 2A-2C 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, FIG. 2A also uses dashed lines to show the electron beam 120 that would be incident on the surface 105 of the mask 100 if the surface 105 of the mask 100 were not electrostatically charged. FIG. 2B shows the reference structure 130 of the mask 100 imaged with the electron beam 220 due to the positive electrostatic charge 200 of the sample. Compared to the reference structure 130 in FIG. 1B, the reference structure 130 of the positively charged mask 100 appears smaller. Figure 2C shows the imaging of the defect 150 and four drift markers 160 acquired by the electron beam 220, resulting from the positive electrostatic charge 200 on the mask of these structural elements. The distance between the drift markers 160 in Figure 2C appears to be shorter compared to the distance in Figure 1B.

[0150] 3A-3C show the same as in FIGS. 2A-2C, except that the mask 100 now has a negative electrostatic charge 300 instead of a positive electrostatic charge 200. The electric field of the sample's negative 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 mask 100 without an electrostatic charge is again shown in dashed lines. As shown in FIG. 3B, the deflection of the electron beam 320 caused by the negative electrostatic charge 300 enlarges the image of the reference structure 130 compared to the image of the reference structure 130 in FIG. 1B. Referring again to FIG. 1C, the same applies to the imaging of the defect 150 and four drift markers 160 in FIG. 3C.

[0151] From the change in size of the reference structure 130 caused by the electrostatic charges 200, 300 on the mask 100, or generally on the sample 100, it is possible to ascertain both the size, i.e., the numerical value, and the mathematical sign of the electrostatic charges 200, 300 on the mask 100. As shown in Figures 3A, 3B, and 3C, the electrostatic charges 200, 300 on the sample may also be ascertained by the measured displacement of the drift markers 160 relative to their reference positions. This likewise applies to the absolute value and mathematical sign of the electrostatic charges 200, 300 on the sample.

[0152] Figure 4 shows an electrically conductive sample 400 in the left-hand image and an electrically insulating sample 450 in the right-hand image. The samples 400, 450 are placed on an electrically conductive sample holder 410 (stage). Figure 4 also shows, schematically, the current that results when the sample 400, 450 is irradiated with an electron beam 420 of current intensity I0. A portion of the electrons 125 of the primary beam 420 that are incident on the sample 400, 450 are backscattered by the sample 400, 450, largely independent of the electrical conductivity of the sample 400, 450. The backscattered electrons (BSE) 430 by the sample 400, 450 generate a current I directed away from the sample 400, 450. BSE forms a current I BSE is proportional to the current intensity of the primary electron current I0 incident on the sample 400, 450, i.e., I BSE=η·I0, where the proportionality constant η is called the yield.

[0153] More typically, the incident current I and the current I generated by the SE 440 leaving the sample 400, 450 SE There is a linear relationship between SE = δ·I0, where δ is a proportionality constant. For the electrically conductive sample 400, the additional current I p 460 can supply charge to the sample 400 or dissipate charge through the grounded sample holder 410. For charge retention reasons, a conductive sample 400 therefore has the following relationship: I=I BSE +I SE +I p Or, rewritten, I p =I0-I BSE -I SE =I0(I-η-δ). This means that the current I p compensates for excess or missing charges on the sample 400, thereby preventing static charging of the sample 400.

[0154] The non-conductive sample 450 in the image on the right side of FIG. 4 has a compensation current I between the sample holder 410 and the sample 450. p prevents the flow of I p = 0. This also applies to an electrically conductive sample 400 that is not grounded, for example due to the mounting surface of the sample holder 410 being made of an electrically insulating material. Now, solving the equation given above for charge retention gives I p =0=I0-I BSE -I SE =I0(1-η-δ). The sample 450 is configured such that the current intensity of the primary electron beam 420 incident on the sample 450 is equal to the current intensity I SE and the current intensity I of BSE430 BSEexactly compensated in absolute value for the accumulated charge Q(t→∞). Otherwise, an equilibrium value Q(t→∞) for t→∞ is established for the accumulated charge (for which a time ranging from a few seconds to a few minutes is typically sufficient, depending on the current strength I and the size or electrical conductivity of the sample). A sample 450 in the form of an electrical insulator will accumulate static charge locally. On the other hand, an ungrounded electrically conductive sample 400 will have the charge Q(t) distributed uniformly across the sample 400.

[0155] As shown in FIG. 5, the BSE yield η and the SE yield δ are functions of the incident energy E of the primary electron beam 420. Graph 500 shows a profile 510 of the sum of the yields η and δ as a function of the incident energy E of the primary electron beam 420, taken from the textbook "Physical Principles of Electron Microscopy," FR Egerton, Springer 2005. An electron beam 420 with very small incident energy generates very few SEs and BSEs. The number of SEs and BSEs cannot compensate for the charge induced on the sample 450 by the electrons 125 of the primary beam 420, causing the sample 450 to carry a negative electrostatic charge 200. As the incident energy E increases, the number of SEs 440 and BSEs 430 generated per incident electron 125 increases, i.e., the yields η and δ of SEs 440 and BSEs 430 rise sharply. When the incident energy E0 reaches a first threshold E1520, the electrons 125 incident on the sample 450 will, on average, generate a total of one SE or one BSE. At incident energy E0=E1, the charge introduced to the sample 450 by the electrons 125 and the charge dissipated from the sample 450 by the SEs 440 and BSEs 430 exactly balance each other, so that the sample 450 does not carry a static charge at incident energy E1520. In FIG. 5, I0=I SE +I BSE The state is represented by dashed line 550.

[0156] When the incident electron energy E0 further increases, the yields η and δ continue to increase in order to reach their maximum values at the incident energy E3. When the incident electron energy E0 increases beyond the value E3, the number of electrons that can detach the electrons 125 of the primary beam 420 from the electron binding further increases, but such electrons are emitted from deeper layers of the sample 450 and can no longer reach the sample surface 105. As a result, the yields η and δ decrease, and thus the number of SEs 440 and BSEs 430 that can leave the samples 400, 450 also decreases accordingly.

[0157] At the incident energy E0 = E2, the charge brought to the sample 450 by the electrons 125 and the charge dissipated from the sample 450 as I SE and I BSE are balanced again. At the incident energy E2530 of the electrons 125 of the primary beam 420, similarly, there are no electrostatic charges 200, 300 in the sample 450. When the incident electron energy E0 is within the energy range E1~E2, the sample 450 has a positive electrostatic charge 200, but outside this energy range, that is, when E0 < E1 and E0 > E2, the sample 450 obtains a negative electrostatic charge 300.

[0158] Most known materials have an energy interval E1 < E2 within which the incident energy of the electrons 125 brings a net positive charge 200 to the material. On the other hand, when the incident energy of the electrons 125 is outside this energy range, the material has a negative electrostatic charge 300. The aforementioned textbook (R.F. Egerton: "Physical Principles of Electron Microscopy", Springer 2005) shows that the incident energy of the electrons 125 is in the range of several hundred electron volts (eV: electron volt) for the lower energy threshold E1 and in the range of about 1 keV to 10 keV for the upper energy threshold E2.

[0159] As already mentioned above, the incident energy E0 of the electrons 125 for imaging and processing the lithography mask 100 are usually different values. One advantage of the method described herein is that the incident energy E0 of the electrons 125 can be optimized for the respective function of the electrons 125, without the accuracy of the respective processing process being compromised by the electrostatic charges 200, 300 on the specimen.

[0160] Diagram 695 of Figure 6 shows the fabrication of an EUV mask 600 by performing a local chemical reaction on absorbing pattern elements 640. The EUV mask 600 comprises an electrically insulating substrate 610, e.g., a quartz substrate. A Bragg mirror 620, e.g., in the form of a multilayer structure 620 comprising alternating silicon and molybdenum layers, is deposited on the substrate 610. An electrically conductive cap layer 630, e.g., in the form of ruthenium (Ru), chromium (Cr), or chromium nitride (CrN), is deposited on the Bragg mirror 620. The cap layer 630 carries the absorbing, electrically conductive pattern elements 640. The pattern elements 640 may comprise, e.g., tantalum (Ta), tantalum nitride (TaN), or tantalum boron nitride (TaBN).

[0161] The active portion of EUV mask 600 is electrically conductive laterally through the metal layer, but the non-conductive substrate 610 of EUV mask 600 electrically insulates EUV mask 600 from sample holder 410 vertically. In addition, the electrically conductive layers of conductive cap layer 630 and Bragg mirror 620 are typically separated by what is known as a black border. This results in larger conductive areas of EUV mask 600 that are separated or insulated from each other laterally by the black border and vertically by the insulating substrate 610.

[0162] The defect 650 in the pattern element 640 may be an absorbent material excess defect or an absorbent material deficiency defect, similar to the defect 150. A gas supply system 660 supplies a precursor gas 670 in the form of a deposition gas (for an excess material defect) or an etching gas (for a deficiency material defect) to the location of the defect 650, i.e., the processing site. In addition, an additive gas may be added to the precursor gas 670. The electron beam 420, having a current intensity I1(PE1), decomposes the precursor gas 670 adsorbed at the processing site, inducing a local chemical etching or deposition reaction. The incident energy E0 of the electrons 125 of the primary electron beam (PE) is selected to be as small as possible (in the range of a few hundred electron volts or less) to minimize the lateral dimensions of the local chemical reaction. Within this range of incident energy E0, the current I2(SE) of the SE 440 and the current I3(BSE) of the BSE 430 caused by the primary electron beam are small. These currents cannot compensate for the charging caused by the primary beam 420 on the EUV mask 600 , and the EUV mask 600 accumulates a negative electrostatic charge 300 .

[0163] The electron beam 420 may also be used to image the EUV mask 600, particularly defects 650 in the EUV mask 600. The defects 650 in the EUV mask 600 may be analyzed before being processed. Furthermore, after defect repair is completed, the processing site may be scanned again by the electron beam 420 to check the success of the repair process. During these process steps, the gas supply system 660 does not supply precursor gas. For the purpose of analyzing the sample, i.e., the EUV mask 600 or defects 650 in the EUV mask 600, the incident energy E0 of the electrons 125 of the electron beam 420 may be increased to optimize the lateral resolution of the primary beam 420 or to confirm the depth profile of the sample. Changing the incident energy E0 changes the degree of electrostatic charge on the EUV mask 600. Depending on the material of the absorbing pattern elements 640 and the incident energy E0 of the electrons 125 of the primary beam 420, the mathematical sign of the electrostatic charge 200, 300 may change.

[0164] 7 illustrates the setting or discharging of the electrostatic charge 200, 300 of the EUV mask 600, which the EUV mask 600 has undergone due to the repair of the defect 650 and / or the analysis of the defect 650 shown in FIG. 6. To set or remove the electrostatic charge 200, 300, in a first step, either the EUV mask 600 or the electron beam source 690 is moved to a location on the mask where the electron irradiation performed for discharging purposes cannot subsequently affect the function of the EUV mask 600. The incident energy E of the electrons of the electron beam 720 is then adjusted to a value that generates an electrostatic charge 200, 300 with an opposite mathematical sign to the electrostatic charge 200, 300 generated during the analysis or processing process. Irradiating the cap layer 630 of the EUV mask 600 with a primary electron beam PE4 720 having incident energy E0 and current intensity I4(PE4) generates an SE740 with a current intensity I6(SE6) and a BSE730 with a current intensity I5(SE5). The difference between the current I4(PE4) on the one hand and the currents I5(BSE5) and I6(SE6) on the other hand causes a charge Q(t) in the cap layer 630 of the EUV mask 600, which reduces or compensates for the electrostatic charges 200 and 300 of the EUV mask 600 caused by the processing of the defect 650. The time required to discharge the electrostatic charges 200 and 300 depends on the charge Q(t→∞) stored in the EUV mask 600 on the one hand and the amount of charge generated per unit time q(t) = I4(PE4) - I5(BSE5) - I6(SE6).

[0165] 7 may be performed before performing an analysis process to identify the location and size of the defect 650 in the EUV mask 600. This allows the location and size of the defect 650 to be determined with the highest possible accuracy, thereby creating the prerequisites for the best possible defect repair. The electrostatic charge 200, 300 on the EUV mask 600 generated by the analysis process may be set to a desired level, for example, a charge Q=0, before performing defect repair. Before imaging the processing site of the EUV mask 600 to identify any remaining residual defects, the electrostatic charge 200, 300 may again be set to a predetermined level.

[0166] The electron beam 720 may be focused onto the cap layer 630 of the EUV mask 600. However, to prevent damage to the EUV mask 600 caused by irradiating it, the primary electron beam 720 may be expanded and directed toward the EUV mask 600, especially if the EUV mask 600 allows it. When using an expanded electron beam 720, care should be taken not to radiate beyond the black border of the mask 600. In this case, only a portion of the electrons will be available to establish the electrostatic charges 200, 300; the remainder will undesirably electrostatically charge areas of the EUV mask 600.

[0167] FIG. 8 illustrates simultaneous analysis or processing of an EUV mask 600 and setting of electrostatic charges 200, 300 on the EUV mask 600. Thus, FIG. 8 combines the contents of FIGS. 6 and 7. Proceeding from FIG. 6, in the example of FIG. 8, a first electron source 690 generating at least one other particle or electron beam irradiates a defect 650 on the EUV mask 600 with electrons 125 of the primary electron beam 420 and a current intensity I1(PE1). The incident energy E0 of the electrons 125 is optimized for performing an analysis or processing process on the defect 650 on the EUV mask 600. Any resulting process failures need not be considered. The second electron beam source 890, more generally the second particle beam source 890, generates at least one particle beam whose electrons 125 are the electron beam 720 adjusted or regulated to an incident energy E0, which irradiates the cap layer 630 of the EUV mask, so that the difference I4(PE4)-I5(BSE5)-I6(SE6) between the currents of the second electron beam source 890 exactly compensates for the difference I1(PE1)-I2(BSE2)-I3(SE3) between the currents of the first electron beam source 690. Thus, 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.

[0168] When transitioning from the fabrication process of the EUV mask 600 to the analysis of the EUV mask 600, the incident energy E0 of the electrons 125 of the electron beam 420 may be changed (and the gas supply system 660 stopped) so that the incident energy E0 of the electrons 125 of the electron beam 720 of the second electron source 890 is adapted to the changed incident energy E0 of the electrons 125 of the electron beam 420.

[0169] FIG. 9 shows an advantageous modification of the setting of the electrostatic charges 200, 300 of the EUV mask 600 discussed in FIGS. 7 and 8. FIG. 9 repeats the setting of the electrostatic charges 200, 300 of the EUV mask 600 from FIG. 7 shown in FIG. 7, with the difference that the primary electron beam 720 is irradiated onto the electrically conductive sacrificial layer 920 instead of the electrically conductive cap layer 630 of the EUV mask 600. The electrically conductive sacrificial layer 920 is deposited on the cap layer 630 of the EUV mask 600. For this purpose, a gas supply system 660 supplies a precursor gas 970 to the site where the sacrificial layer 920 is to be deposited. The precursor gas 970 may include a metal carbonyl, in particular molybdenum hexacarbonyl (Mo(CO)6). The precursor gas 970 may further contain one or more additive gases. At least one additive gas may include an oxidizer, for example, nitrogen dioxide (NO2).

[0170] The electrically conductive sacrificial layer 920 protects the cap layer 630 of the EUV mask 600 from potential damage caused by irradiation by the electron beam 720. The electrically conductive sacrificial layer 920 therefore acts as a protective layer. The sacrificial layer 920 therefore prevents the ions of the particle beam 720 from damaging the EUV mask 600 and allows for the use of more massive particles, such as ions, to set the electrostatic charge of the EUV mask 600. Because the sacrificial layer 920 is not critical to the functioning of the EUV mask 600 and is very far from the processing site of the defect 650, the sacrificial layer 920 may be deposited on the cap layer 630 of the EUV mask 600 at a location where the second radiation source 890 emits the second particle beam 720 onto the sacrificial layer 920 to set the electrostatic charge 200, 300 of the EUV mask 600, while still allowing the use of the first radiation source 690 with the first particle beam 420 to process the defect 650. As an example, the first radiation source 690 may direct electrons 125 at the defect 650 and the second radiation source 890 may emit ions onto the sacrificial layer 920 of the EUV mask 600 .

[0171] The sacrificial layer 920 may be removed from the EUV mask 600 using a mask cleaning process after processing is complete.

[0172] Diagram 1095 of FIG. 10 illustrates the setting of electrostatic charges 200, 300 on a transmissive photomask 1000. The transmissive photomask 1000 comprises a non-electrically conductive quartz substrate 1010. Absorbent, electrically 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, as reproduced in FIG. 1095, have defects 1050. The defects 1050 may be dark defects, i.e., excess absorber material defects, or bright defects, i.e., absorber material missing defects. An electrically conductive sacrificial or protective layer 1070 is deposited on the substrate 1010 of the transmissive mask 1000 and extends to the defect pattern elements 1040. The electrically conductive sacrificial layer 1070 may be deposited on the substrate 1010 by a particle beam induced deposition process by supplying a precursor gas 1080 and a particle beam 720, e.g., an electron beam 720, that is adsorbed on the substrate 1010 of the mask 1000. The precursor gas 1080 may include, by way of example, 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 oxidizer, e.g., oxygen (O2), water (HO), or nitrogen dioxide (NO2).

[0173] In the example of FIG. 10 , drift markers 1030 are deposited on a sacrificial layer 1070. Drift markers 1030 may similarly be deposited on the sacrificial layer 1070 by a particle-beam-induced deposition process. A particle beam 720 from a radiation source 690 may be used for this purpose. Preferably, a metal carbonyl may again be used as a precursor gas 1090, optionally in combination with an additive gas such as oxygen (O ), a halogen-containing gas, or nitrogen dioxide (NO ). By way of example, chromium hexacarbonyl (Cr(CO) ) or molybdenum hexacarbonyl (Mo(CO) ) may again be used as the metal carbonyl. Here, it is preferable to use a precursor gas 1090 for depositing drift markers 1030 that is separate from the precursor gas for depositing the sacrificial or protective layer 1070. When the drift markers 1030 are imaged by the electron beam 720, the reference elements 1030 are further demarcated from the sacrificial layer 1070 by material contrast in addition to surface topography contrast.

[0174] In the schematic cross-sectional view shown in FIG. 10 , drift markers 1030 are deposited on a sacrificial layer 1070. Preferably, at least three drift markers 1030 are deposited on the sacrificial layer 1070 around the defect 1050. These drift markers 1030 span a two-dimensional coordinate system in the plane of the mask 1000. The drift markers 1030 are scanned by the electron beam 720 to ascertain a reference position of the drift markers 1030 before the defect 1050 is processed. From the reference position of the drift markers 1030, it is further possible to ascertain whether the mask 1000 has electrostatic charges 200, 300. This requires a calibration measurement in which the position of the drift markers 1030 is ascertained as a function of the electrostatic charge on the mask 1000.

[0175] During defect repair, the processing of defect 1050 is periodically interrupted. The electron beam 720 is switched from the processing mode with the first incident energy E0(B) to the analysis mode with the second incident energy E0(A), and the drift marker 1030 is scanned in the analysis mode. As described above, it may be advantageous to select E0(B) < E0(A). From the acquired measurement data, it is possible to identify the relative displacement between the drift marker 1030 and the electron beam 720. In addition, from the displacement of the drift marker 1030 based on the reference position of the drift marker 1030, it is possible to confirm the magnitude and mathematical sign of the electrostatic charges 200, 300 of the mask 1000.

[0176] After the protective layer or sacrificial layer 1070 and the drift marker 1030 are fabricated, after the electron beam 720 is appropriately adjusted, that is, after the incident energy E0 is adjusted, the electron beam 720 may irradiate the sacrificial layer 1070 to set the electrostatic potential before performing the first stage of defect 1050 repair. After interrupting the defect repair, before scanning the drift marker 1030, the electron beam 720 may be adjusted to set the electrostatic charges 200, 300 of the mask 1000 to a desired level. The electron beam 720 is then switched to the analysis mode and the drift marker 1030 is scanned. From such scanning data, the drift between the defect 1050 and the electron beam 720 is identified and corrected. In addition, the electrostatic charges 200, 300 of the mask 1000 are confirmed from the scanning data. If necessary, the electrostatic charges 200, 300 are set or reduced to a predetermined potential before continuing the processing.

[0177] These process steps are repeated until the remaining defects that still exist no longer interfere with the imaging behavior of the mask 1000 to an unacceptable extent, that is, until no transferable defects occur. After the defect 1050 repair process is completed, the sacrificial layer 1070 is preferably removed from the mask 1000 in a mask cleaning process, together with the drift marker 1030 on the sacrificial layer 1070.

[0178] 11, similar to FIG. 8, illustrates the simultaneous analysis or processing of a transmission mask 1000 and the setting of electrostatic charges 200, 300 on the transmission mask 1000 using two radiation sources 690 and 890 that generate at least one particle beam and at least one other particle beam. The first radiation source 690 emits an electron beam 420 of current intensity I1 (PE11) that irradiates the mask 1000, for example to analyze a defect 1050, and the BSE 430 and SE 430 generate currents I2 (BSE2) and I3 (SE3) that leave the mask 1000. The incident energy E0 of the primary electron beam 420 is adapted to perform the defect analysis. 11, the second radiation source 890 radiating onto the electrically conductive sacrificial layer 1070 provides an electron beam 720 with an incident energy E0, and the current intensity I4(PE4) of the electron beam 720 is adjusted so that the charge generated per unit time on the sacrificial layer 1070 thereby exactly balances the charge generated on the pattern elements 1040 by the electron beam 420. This makes it possible to prevent electrostatic charges 200, 300 on the mask 1000 during the analysis process or to keep the electrostatic charges 200, 300 at a predetermined level.

[0179] Before performing repair of the defect 1050, the incident energy E of the electrons 125 of the electron beam 420 is optimized for the repair process. Furthermore, the gas supply system 660 is activated to supply a precursor gas 1170 to the location of the defect. In addition, the incident energy E of the electron beam 720 from the radiation source 890 is adapted to the changed incident energy of the electron beam 420, so that the two electron beams generate charges of equal amounts per unit time but of opposite mathematical signs on the pattern element 1040 and the sacrificial layer 1070, respectively. This ensures that electrostatic charging of the sample 1000 can be avoided even during sample processing.

[0180] 12 shows a further embodiment of the method for establishing an electrostatic charge 200, 300 on a sample 100, 600, 1000 described herein. The sample 100, 600, 1000 is either an electrical insulator that accumulates a local charge when locally irradiated with a particle beam 120, 420, 720, or an ungrounded electrical conductor. In an electrical conductor, free electrons generated locally by the irradiation are distributed throughout the sample 100, 600, 1000. The samples 100, 600, 1000 under consideration may be insulated from one another but may also comprise larger electrically conductive regions.

[0181] The image 1200 in the upper part shows the time profile of the electrostatic charge 1210 on the sample 100, 600, 1000, which is uncharged at the start of the process. In the example shown in FIG. 12, charge is generated on the sample 100, 600, 1000 at a constant rate over time (q(t)=c), similar to a capacitor being charged with a constant current over time. Of course, other time profiles of the electrostatic charge are possible. In the example shown in FIG. 12, the sample 100, 600, 1000 is negatively charged. That is, the sample 100, 600, 1000 is irradiated by electrons with an incident energy E0 outside the energy interval E1-E2 of FIG. 5.

[0182] The horizontal dashed line indicates the critical charge or critical potential level 1220. For electrostatic charges below the critical potential level 1220 in absolute value, an electric field is generated by the sample 100, 600, 1000, but only interferes with the charged particle beam 120, 420, 720 to an acceptable extent. On the other hand, above the line of the critical potential level 1220, the electric field caused by the electrostatic charge 1210 deflects the charged particles 125 from the desired trajectory, thereby impairing the analysis and / or processing to an unacceptable extent. This is equally true for positive electrostatic charges greater (in absolute value) than the positive electrostatic charge 1270 (see image 1295 in the lower part of FIG. 12). In the upper portion of the image 1200, the sample 100, 600, 1000 can be irradiated by the particle beam 120, 420, 720 within the time interval starting from zero to time 1230 without violating specifications.

[0183] The image 1295 in the lower part of Fig. 12 presents the temporal profile of the electrostatic sample 100, 600, 1000 in the image 1200 in the upper part, where the sample has a positive electrostatic charge 1270 at the beginning of the irradiation process, the absolute value of which reaches a critical threshold 1220. The positive charging 1270 of the sample can be achieved, for example, by irradiation with electrons 125 whose charging energy E0 is within the energy interval E1-E2 (Fig. 5) such that the irradiated sample 100, 600, 1000 becomes positively charged. In the example shown in Fig. 12, the electrostatic charge 1260 has been shifted by the time interval from zero to time 1290 compared to the partial image 1200, as a result 1270 of the sample 100, 600, 1000 being previously positively charged. This makes it possible to double the time 1280 during which analysis or processing can be performed by irradiation with the charged particle beam 120, 420, 720 without violating specifications.

[0184] 13 shows a schematic cross-sectional view through some important parts of a device 1300 that can be used to set the electrostatic charge 200, 300 on a sample 100, 600, 1000, in particular a lithography mask 100, 600, 1000. The exemplary device 1300 of FIG. 13 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.

[0185] The device 1300 comprises a particle beam source 1305 in the form of an electron beam source 1305 that generates an electron beam 1315 as a particle beam 1315. The electron beam 1315 has the advantage over an ion beam that the electrons 125 incident on the sample 1325 or lithography mask 100, 600, 1000 cannot substantially damage the sample or mask 100, 600, 1000. However, it is also possible to use an ion beam, an atomic beam, a molecular beam, or a photon beam (not shown in FIG. 13 ) for processing the sample 1325 with the device 1300.

[0186] The scanning particle microscope 1310 comprises an electron beam source 1305 and a column 1320 in which is arranged a beam optics unit 1313, e.g., in the form of an electron optics unit of the SEM 1310. In the SEM 1310 of Figure 13, the electron beam source 1305 generates an electron beam 1315 that is directed as a focused electron beam 1315 by imaging elements arranged in the column 1320, which imaging elements are not shown in Figure 13, towards a site 1322 of a sample 1325, which may include a lithography mask 100, 600, 1000. The beam optics unit 1313 thus forms the imaging system 1313 of the electron beam source 1305 of the SEM 1300. The electron beam 1315 of the electron beam source 1305 represents one possible embodiment of one particle beam or another.

[0187] The imaging element of the column 1320 of the SEM 1310 may further be scanned by the electron beam 1315 across a sample 1325. The sample 1325 may be inspected, i.e., analyzed and processed, using the electron beam 1315 of the SEM 1310. An aperture or an aperture system (not shown in FIG. 13) comprising multiple apertures may be mounted in the column 1320 of the SEM 1310, preferably downstream of the collecting lens of the SEM 1310. The aperture or aperture system may be adjusted by a configuration unit 1390 of the computer system 1380 of the device 1300.

[0188] In the interaction region of the sample 1325, backscattered electrons (BSEs) and secondary electrons (SEs) generated by the electron beam 1315 are recorded by a detector 1317. A detector 1317 located within the electron column 1320 is called an "in-lens detector." In various embodiments, the detector 1317 may be installed within the column 1320. The detector 1317 converts the SEs generated at the measurement point 1322 by the electron beam 1315 and / or the BSEs backscattered by the sample 1325 into electrical measurement signals and transfers the electrical measurement signals to an evaluation unit 1385 of the computer system 1380 of the device 1300. The detector 1317 may incorporate a filter or filter system (not reproduced in FIG. 13 ) for discriminating SEs and BSEs in terms of energy and / or solid angle. The detector 1317 is controlled by a configuration unit 1390 of the device 1300.

[0189] The exemplary device 1300 may also comprise a second detector 1319, which may be designed in particular to detect electromagnetic radiation in the X-ray range, so that the detector 1319 makes it possible to analyze the material composition of the radiation generated by the sample 1325 during its examination. The detector 1319 is likewise controlled by the configuration unit 1390.

[0190] Device 1300 may further include a third detector (not shown in FIG. 13), often embodied in the form of an Everhart-Thornley detector, typically located outside of column 1320. The third detector is typically used to detect SEs.

[0191] The device 1300 includes a flood gun 1303. The flood gun 1303 can provide ions with low kinetic energy to a region of the sample 1325. The flood gun 1303 can further be configured to provide electrons with a configurable incident energy E to the region of the sample 1325 to be processed and / or analyzed. The ions with low kinetic energy and / or the electrons 125 with the configurable incident energy E can compensate for the electrostatic charge 200, 300 of the sample 1325. Furthermore, the ions or electrons from the flood gun 1303 can be used to set the electrostatic charge 200, 300 of the sample to a predetermined charge level. The flood gun 1303 thus represents an exemplary embodiment of a particle beam.

[0192] Instead of or in addition to the flood gun 1303, the device 1300 may include a second particle beam source 890 (not reproduced in FIG. 13 ) that generates the second particle beam 720. The second particle beam source 890 may include the same or similar imaging elements as the first particle beam source 1305. The second particle beam source 890 may additionally include one or both of the detectors 1317, 1319. This means that the device 1300 may also include a second scanning particle microscope (not shown in FIG. 13 ).

[0193] The device 1300 may further comprise a mesh (not shown in FIG. 13) at the output of the column 1320 of the modified SEM 1310. By applying a voltage between the mesh and a metal tube (liner tube) attached to the objective lens region of the column 1320, also not shown in FIG. 13, it is possible to generate a configurable damping voltage for the electrons 125 of the electron beam 1315, thereby adjusting the incident energy E of the electrons 125 to a desired value. In addition, the mesh may also be used to compensate for electrostatic charges 200, 300 on the sample 1325. Furthermore, the mesh may be grounded.

[0194] In addition to the electron beam source 1305, the device 1300 may include a second radiation source 890 (not shown in FIG. 13 ), which may be a second electron beam source 890 or may be a source of another type of particle, such as ions, atoms, molecules, or high-energy photons.

[0195] The sample 1325 is placed on a sample stage 1330 or sample holder 1330 for inspection. The sample stage 1330 is also known in the art as a "stage." The sample stage 1330 can be moved in three spatial directions relative to the column 1320 of the SEM 1310, as represented by the arrows in FIG. 13 , e.g., by a micromanipulator (not shown in FIG. 13 ). In particular, the sample stage 1330 can move the sample 1325 from at least one site 630, 920, 1070 where the conditioned particle beam 720 is emitted onto the sample 1325, to at least one site 150, 650, 1050 or defect 150, 650, 1050 to be analyzed or machined.

[0196] In addition to translation, the sample stage 1330 may be rotated about an axis oriented at least parallel to the beam direction of the particle beam source 1305. The sample stage 1330 can also be embodied such that the sample stage 1330 is rotatable about one or two additional axes, one or two of which are arranged in the plane of the sample stage 1330. Preferably, two or three rotation axes form a Cartesian coordinate system. As can be inferred from FIG. 13 , rotation of the sample stage 1330 about a rotation axis arranged in the plane of the sample stage 1330 is often only possible to a limited extent due to the short distance between the end of the column and the sample 1325.

[0197] The inspected sample 1325 may be part of any microstructured part or component that requires analysis and possibly subsequent processing, for example repair of local defects 150, 600, 1050 in a lithography mask 150, 650, 1000. The sample 1325 may thus, by way of example, comprise a transmission photomask 1000 or a reflection photomask 600, and / or a template for nanoimprint technology. The transmission photomask 1000 and the reflection photomask 600 may comprise any kind of photomask, such as a binary mask, a phase-shift mask, an OMOG mask, or a mask for double or multiple exposure.

[0198] The device 1300 of FIG. 13 may further include one or more scanning probe microscopes, for example in the form of atomic force microscopes (AFMs) (not shown in FIG. 13), which may be used to analyze and / or process the sample 1325.

[0199] The exemplary scanning electron microscope 1310 shown in Figure 13 is operated within a vacuum chamber 1301. The SEM 1310 of Figure 13 includes a pumping system 1307 to create and maintain the necessary reduced pressure within the vacuum chamber 1301.

[0200] The device 1300 comprises a computer system 1380. The computer system comprises a setting unit 1390 configured to set the incident energy E of the electrons 125 of the electron beam 1315 to a predetermined value. For this purpose, the evaluation unit 1385 can set an acceleration voltage of the electrons 125 of the electron beam 1315 as well as a braking voltage of the electrons 125.

[0201] The computer system 1380 may further comprise an interface 1370 through which the computer system 1380 receives information about the specimen 1325, such as information about the material composition of the specimen 1325 and / or information about the surface topography of the specimen 1325. The computer system 1380 may also receive information about defects 150, 650, 1050 on the specimen 1325. The computer system 1380 may further comprise a user interface 1375 through which a user provides the computer system 1380 with an incident energy E of the electrons 125 of the electron beam 1315. However, it is also possible that the user provides the computer system 1380 with only a possible energy range for setting the incident energy E of the electrons 125 of the electron beam 1315 via the user interface 1375, the computer system 1380 confirms the incident energy E of the electrons 125 of the electron beam 1315, and a setting unit 1390 of the computer system 1380 sets the acceleration voltage and / or braking voltage accordingly.

[0202] The computer system 1380 may also include a scanning unit 1382 that scans the electron beam 1315 across the sample 1325. The setting unit 1390 may be further configured to set various parameters of the modified scanning particle microscope 1310 of the device 1300. The setting unit 1390 may also control the rotation of the micromanipulator and the sample stage 1330. The computer system 1380 may also be configured to control the flood gun 1303 and / or the second radiation source 890 or scan across the sample 1325.

[0203] The evaluation unit 1385 of the computer system 1380 may further analyze the measurement signals from the detectors 1317 and 1319 and generate therefrom an image of the specimen 1325 that can be displayed on a display 1395. The evaluation unit 1385 may be particularly designed to identify the location and shape of missing material defects 650, 1050 and / or excess material defects 150, 650, 1050 on the specimen 1325, e.g., on the lithography mask 100, 600, 1000, based on the measurement data from the detector 1317.

[0204] The evaluation unit 1385 may further include one or more algorithms that enable determining the size and mathematical sign of the electrostatic charges 200, 300 on the sample 1325 based on the images of the one or more reference structures 130. The evaluation unit 1385 may further include one or more algorithms designed to determine the degree and mathematical sign of the electrostatic charges 200, 300 on the sample based on the shift in the position of the three or more drift markers 1030. The evaluation unit 1385 further includes one or more algorithms designed to determine the incident energy E0 of the particles 125 of the particle beam 1315 used to set or compensate the electrostatic charges 200, 300 on the sample based on the determined electrostatic charges 200, 300, the material composition of the sample 1325, and the surface topography of the sample 1325. The algorithms of the evaluation unit 1385 may be implemented using hardware, software, or a combination thereof. The algorithm(s) may be implemented in particular in the form of an ASIC (application-specific integrated circuit) and / or an FPGA (field-programmable gate array).

[0205] The computer system 1380 and / or the evaluation unit 1385 may comprise a memory, preferably a non-volatile memory (not shown in FIG. 13 ), for storing a material database of the sample 1325 and repair morphology models for various types of masks 100, 600, 1000. The evaluation unit 1385 may be designed to calculate repair morphologies of one or more defects 150, 650, 1050 in the lithography mask 600, 1000 based on the repair models from measurement data from the detector 1317. The computer system 1380 may further comprise an interface 1370 for exchanging data with the Internet, an intranet, and / or some other device. The interface 1370 may include a wireless or wired interface. The evaluation unit 1385 may provide the setting unit 1390 with data that enables adjusting the incident energy E of the particles 125 of the particle beam 1315 automatically, i.e., without user interaction.

[0206] The evaluation unit 1385 and / or the configuration unit 1390 may be integrated into the computer system 1380 as shown in Figure 13. However, it is also possible for the evaluation unit 1385 and / or the configuration unit 1390 to be embodied as stand-alone units inside or outside the device 1300. The evaluation unit 1385 and / or the configuration unit 1390 may be specifically designed to perform some of the tasks of the evaluation unit 1385 and / or the configuration unit 1390 by means of dedicated hardware implementations.

[0207] Computer system 1380 may further be integrated into device 1300 or may be designed as a stand-alone device (not shown in FIG. 13). Computer system 1380 may be embodied using hardware, software, firmware, or a combination thereof.

[0208] The gas supply system 660 implemented by the device 1300 is discussed below. The sample 1325 is placed on the sample stage 1330, as already described above. The imaging element of the column 1320 of the SEM 1310 can focus and scan the electron beam 1315 across the sample 1325. The electron beam 1315 of the SEM 1310 may be used to induce particle beam-induced deposition (EBID) and / or etching (EBIE) processes. The example device 1300 of FIG. 13 includes three different supply vessels 1340, 1350, and 1360 that store various precursor gases for carrying out these processes.

[0209] The first supply container 1340 stores a precursor gas, for example, 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 lithography mask 100, 600, 1000 may be deposited on the lithography mask 100, 600, 1000, for example, by a local chemical deposition reaction. Furthermore, a protective layer 1070 or a sacrificial layer 1070 may be deposited on the mask 600, 1000 by the precursor gas stored in the first storage container 1340. In addition, a drift marker 1030 may be deposited on the mask 600, 1000 or the sacrificial layer 1070 by the precursor gas stored in the first storage container 1340.

[0210] The electron beam 1315 of the SEM 1310 acts as an energy source for decomposing a precursor gas stored in a first supply container 1340 at the site intended for material deposition on the sample 1325. This means that the combined supply of the electron beam 1315 and the precursor gas leads to an EBID process in which localized deposition of missing material, e.g. material missing from the mask 600, 1000, is performed.

[0211] The electron beam 1315 may be focused to a spot diameter on the order of a few nanometers. The interaction region, or scattering cone, where the electron beam 1315 generates SEs depends first on the energy of the electron beam 1315 and second on the composition of the material onto which the electron beam 1315 is incident. The diameter of the interaction region is in the low single-digit nanometer range. Therefore, the diameter of the scattering cone of the electron beam 1315 limits the achievable resolution when performing localized particle beam-induced reactions. This resolution limit is currently in the single-digit nanometer range.

[0212] 13, the second supply container 1350 stores an etching gas that enables a localized electron beam induced etching (EBIE) process to be performed. The electron beam induced etching process can be used to remove excess material from the sample 1325, such as excess material of the pattern elements 640, 1040 from the mask 600, 1000. The etching gas may include, by way of example, xenon difluoride (XeF), a halogen, or nitrosyl chloride (NOCl).

[0213] Additive or additional gases may be stored in third supply vessel 1360, which can be added as needed to the etching gas held available in second supply vessel 1350 or to the precursor gas stored in first supply vessel 1340. Third supply vessel 1360 may alternatively store a second precursor gas or a second etching gas.

[0214] 13 , each of the supply vessels 1340, 1350, and 1360 of the gas supply system 660 is provided with its own control valve 1342, 1352, and 1362 in order to monitor or control the amount of the corresponding gas supplied per unit time, i.e., the volumetric flow rate of the gas at the site 1322 of the sample 1325 where the electron beam 1315 is incident. The control valves 1342, 1352, and 1362 may be controlled or monitored by a setting unit 1390 of the computer system 1380. This means that a wide range of partial pressure conditions of one or more gases supplied to the processing location for performing the EBID and / or EBIE processes can be set.

[0215] Further, in the exemplary device 1300 of FIG. 13, each supply vessel 1340, 1350, and 1360 includes its own gas supply path system 1345, 1355, and 1365, in which nozzles 1347, 1357, and 1367 terminate near the point of incidence of the electron beam 1315 on the sample 1325.

[0216] The supply vessels 1340, 1350, and 1360 may be provided with their own temperature setting and / or temperature control elements that allow both cooling and heating of the corresponding supply vessels 1340, 1350, and 1360. This allows the precursor gases to be stored at, and particularly supplied at, optimal temperatures, respectively (not shown in FIG. 13). A setting unit 1390 can control the temperature setting and temperature control elements of the supply vessels 1340, 1350, and 1360. During the EBID and EBIE fabrication processes, the temperature setting elements of the supply vessels 1340, 1350, and 1360 may further be used to set the vapor pressure of the precursor gases stored in the supply vessels by selecting an appropriate temperature.

[0217] The device 1300 may include multiple supply vessels 1340 for storing two or more precursor gases. The device 1300 may further include multiple supply vessels 1350 for storing two or more etching gases (not shown in FIG. 13).

[0218] 14 further illustrates key steps of a method for setting the electrostatic charge 200, 300 on a specimen 100, 600, 1000, 1325. The method begins at step 1410. In step 1420, at least one parameter of the at least one particle beam 120, 420, 720, 1315 is adjusted so that each particle 125 of the at least one particle beam 120, 420, 720, 1325 incident on the specimen 100, 600, 1000, 1325 emits, on average, a predetermined average number of electrons from the specimen 100, 600, 1000 being repaired. The at least one parameter may be adjusted, for example, by setting the incident energy E 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 set or adjust the acceleration and / or braking voltages of the particles 125 of the at least one particle beam 120, 420, 720, 1325 accordingly.

[0219] In step 1430, at least one conditioned particle beam 720 irradiates at least one first portion 620, 930, 1070 of the sample 100, 600, 1000, 1325 to set an electrostatic charge 200, 300 on the sample 100, 600, 1000, 1325.

[0220] In step 1440, at least one particle beam 120, 420, 720, 1325 is realigned and / or at least one other particle beam 120, 420, 1325 is aligned to analyze and / or process at least one second portion 150, 650, 1050 of the sample 100, 600, 1000, 1325.

[0221] Next, in step 1450, the sample 100, 600, 1000, 1325 is irradiated with the reconditioned particle beam 720 or other conditioned particle beam 420 at at least one second portion 150, 650, 1050, wherein the at least one first portion 620, 930, 1070 and the at least one second portion 150, 650, 1050 are separated by a predetermined distance and electrically connected to each other.

[0222] The method ends at step 1460.

[0223] 15 illustrates the key steps of another method for setting the electrostatic charge 200, 300 on a specimen 100, 600, 1000, 1325. The method begins at step 1510. In step 1520, at least one parameter of the at least one particle beam 120, 420, 720, 1325 is adjusted so that each particle 125 of the at least one particle beam 120, 420, 720, 1325 incident on the specimen 100, 600, 1000, 1325 emits, on average, a predetermined average number of electrons from the specimen 100, 600, 1000, 1325. The at least one parameter may be adjusted, for example, by setting the incident energy E 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 set or adjust the acceleration and / or braking voltages of the particles 125 of the at least one particle beam 120, 420, 720, 1325 accordingly.

[0224] In step 1530, the sample 100, 600, 1000, 1325 is irradiated with at least one conditioned 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. 1. A method (1400) for establishing an electrostatic charge (200, 300) on a sample (100, 600, 1000, 1325), comprising: adjusting (1420) at least one parameter of at least one particle beam (120, 420, 720, 1315) such that each particle (125) of said at least one particle beam (120, 420, 720, 1315) incident on said sample (100, 600, 1000, 1325) emits, on average, a predetermined average number of electrons from said sample (100, 600, 1000, 1325); b. irradiating (1430) at least one first portion (630, 920, 1070) of the sample (100, 600, 1000, 1325) with the at least one conditioned particle beam (720) to establish the electrostatic charge (200, 300) of the sample (100, 600, 1000, 1325); c. readjusting (1440) at least one parameter of said 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 portion (150, 650, 1050) of said sample (100, 600, 1000, 1325); d. irradiating (1450) the at least one second portion (150, 650, 1050) of the sample (100, 600, 1000, 1325) with the realigned 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 portion (630, 920, 1070) and the at least one second portion (150, 650, 1050) are separated by a predetermined distance and electrically conductively connected to each other; The method (1400) includes:

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

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

4. 4. The method according to claim 1 or 3, wherein the at least one particle beam irradiates the at least one first portion according to a first adjustment, irradiates the at least one second portion according to a second adjustment for processing purposes, and / or irradiates the at least one second portion according to a third adjustment for analysis purposes.

5. 3. The method according to claim 1, wherein the at least one particle beam irradiates the at least one first portion according to a first adjustment and the at least one other particle beam irradiates the at least one second portion according to a first adjustment to process the at least one second portion, or the at least one particle beam irradiates the at least one first portion according to a second adjustment and the at least one other particle beam irradiates the at least one second portion according to a second adjustment to analyze the at least one second portion.

6. 6. The method according to claim 1, wherein the predetermined distance is selected such that the illumination of the at least one first portion by the at least one particle beam at the predetermined distance does not substantially affect the illumination of the at least one second portion by the at least one particle beam or the at least one other particle beam for analyzing and / or processing the at least one second portion of the sample.

7. 7. The method (1400) according to any one of claims 1 to 6, wherein the predetermined distance between the at least one first portion (630, 920, 1070) and the at least one second portion (150, 650, 1050) comprises at least a length or a width of a scanning area of ​​the at least one particle beam (120, 420, 720, 1315) and / or a scanning area of ​​the at least one other particle beam.

8. 8. The method (1400) of any one of claims 1 to 7, wherein the irradiating the at least one second location (150, 650, 1050) comprises supplying at least one precursor gas (670) to the at least one second location (150, 650, 1050) to irradiate the at least one second location (150, 650, 1050).

9. 9. The method according to claim 1, wherein the concentration of the at least one precursor gas in the at least one first region is less than 50% of the maximum concentration in the at least one second region to be processed, preferably less than 10% of the maximum concentration in the at least one second region to be processed, more preferably less than 1% of the maximum concentration in the at least one second region to be processed, and most preferably less than 0.1% of the maximum concentration in the at least one second region to be processed.

10. 10. The method (1400) according to any one of claims 1 to 9, wherein the predetermined distance between the at least one first region (630, 920, 1070) and the at least one second region (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. 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) to process the at least one second portion (150, 650, 1050); locating 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 position at which the at least one particle beam (120, 420, 720, 1315) and / or the at least one other particle beam (120, 420, 1315) is incident on the at least one second portion (150, 650, 1050) by the identified deviation; continuing the irradiation (1450) with the at least one particle beam (120, 420, 720, 1315) and / or the at least one other particle beam (120, 420, 1315) to process the at least one second portion (150, 650, 1050); The method (1400) of any one of claims 1 to 10, further comprising:

12. 1. A method (1500) for establishing an electrostatic charge (200, 300) on a sample (100, 600, 1000, 1325), comprising: adjusting (1520) at least one parameter of at least one particle beam (120, 420, 720, 1315) such that each particle (125) of said at least one particle beam (120, 420, 720, 1315) incident on said sample (100, 600, 1000, 1325) emits, on average, a predetermined average number of electrons from said sample (100, 600, 1000, 1325); b. irradiating (1530) the sample (100, 600, 1000, 1325) with the at least one conditioned particle beam (720) to set the electrostatic charge (200, 300) on the sample (100, 600, 1000, 1325); c. supplying at least one precursor gas (670) to a processing site (1322) of the sample (100, 600, 1000, 1325) during the irradiation of the sample (100, 600, 1000, 1325) with the at least one tailored particle beam (420) to repair at least one defect (150, 650, 1050) in the sample (100, 600, 1000, 1325); The method (1500) includes:

13. The adjustment (1420, 1440, 1520) of the at least one parameter of the at least one particle beam (120, 420, 720, 1315) and / or the at least one parameter of the at least one other particle beam (120, 420, 1315) may be adjusted to include an incident energy of the particles (125) of the at least one particle beam (120, 420, 720, 1315) and / or the particles (125) of the at least one other particle beam (120, 420, 1315) incident on the sample (100, 600, 1000, 1325) and an incident energy 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) incident on the sample (100, 600, 1000, 1325). the wavelength of the particles (125) of the child beam (120, 420, 1315), the flux density of the particles (125) of the at least one particle beam (120, 420, 720, 1315) and / or the particles (125) of the at least one other particle beam (120, 420, 1315) incident on the sample (100, 600, 1000, 1325), and the wavelength of the particles (125) of the child beam (120, 420, 1315) incident on the sample (100, 600, 1000, 1325).

13. The method (1400, 1500) according to claim 1, comprising varying at least one parameter from the group consisting of: a time period during which the particles (125) of the at least one particle beam (120, 420, 720, 1315) are incident on a particle beam (120, 420, 720, 1315) and / or a time period during which the particles (125) of the at least one other particle beam (120, 420, 1315) are incident on a particle beam (120, 420, 720, 1325).

14. 14. The method according to claim 1, wherein said adjusting of said at least one parameter further comprises at least one of specifying a current intensity and / or a flux density of said at least one particle beam and specifying an irradiation time of said sample by said at least one particle beam and / or said at least one other particle beam.

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

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

18. 18. The method (1500) of any one of claims 12 to 17, further comprising the step of electrically connecting a second portion (150, 650, 1050) of the sample (100, 600, 1000, 1325) to be analyzed and / or processed to at least one first portion (920) of the sample (100, 600, 1000, 1325), wherein the second portion (150, 650, 1050) to be analyzed and / or processed and the at least one first portion (920) are separated from each other by a predetermined distance.

19. 19. The method of claim 12, wherein the sample comprises at least one defect having an electrically conductive protective layer disposed around at least a portion of the defect, the at least one adjusted second particle beam irradiating the at least one defect, and the at least one adjusted first particle beam irradiating the electrically conductive protective layer.

20. 20. The method (1400, 1500) according to any one of claims 1 to 19, further comprising determining the electrostatic charge (200, 300) on the sample (100, 600, 1000, 1325) by at least one of the following factors: a change in size of at least one reference structure (130) on the sample (100, 600, 1000, 1325) or a drift correction of the at least one adjusted particle beam (420, 720) during analysis and / or processing of the sample (100, 600, 1000, 1325).

21. 21. The method (1400, 1500) according to any one of claims 1 to 20, further comprising the step of: before processing and / or analyzing the sample (100, 600, 1000, 1325), in particular at least one defect (150, 650, 1050) of the sample (100, 600, 1000, 1325), in accordance with at least one second adjustment of the at least one particle beam (120, 420, 720, 1315), the sample (100, 600, 1000, 1325) is charged with an electrostatic charge (200, 300) within a predetermined potential interval (1270) by irradiating the sample (100, 600, 1000, 1325) with the at least one particle beam (120, 420, 720, 1315) in accordance with a first adjustment.

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

23. A device (1300) for setting an electrostatic charge (200, 300) on a sample (100, 600, 1000, 1325), comprising: a. means (1420) for adjusting at least one parameter of at least one particle beam (120, 420, 720, 1315) such that each particle (125) of said at least one particle beam (120, 420, 720, 1315) incident on said sample (100, 600, 1000, 1325) emits, on average, a predetermined average number of electrons from said sample (100, 600, 1000, 1325); b. means (1430) for irradiating at least one first portion (630, 920, 1070) of said sample (100, 600, 1000, 1325) with said at least one conditioned particle beam (720) to establish said electrostatic charge (200, 300) on said sample (100, 600, 1000, 1325); c. means (1440) for conditioning at least one other particle beam (720) to analyze and / or process at least one second portion (150, 650, 1050) of said sample (100, 600, 1000, 1325); d. A means (1450) for irradiating the at least one second portion (150, 650, 1050) of the sample (100, 600, 1000, 1325) with the reconditioned at least one particle beam (120, 420, 720, 1315) and / or the conditioned at least one other particle beam (120, 420, 1315), wherein the at least one first portion (630, 920, 1070) and the at least one second portion (150, 650, 1050) are separated by a predetermined distance and electrically conductively connected to each other; A device (1300) comprising:

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

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

26. The means (1420, 1440, 1520) for adjusting the at least one parameter of the at least one particle beam (120, 420, 720, 1315) and / or the at least one parameter of the at least one other particle beam (120, 420, 1315) may comprise: means for setting an acceleration voltage for the particles (125) of the at least one particle beam (120, 420, 720, 1315) and / or the particles (125) of the at least one other particle beam (120, 420, 1315); means for setting a damping voltage for the particles (125) of the at least one particle beam (120, 420, 720, 1315) and / or the particles (125) of the at least one other particle beam (120, 420, 1315); 26. The device (1300) according to claim 23, comprising at least one element of: means for setting a wavelength of the particles (125) of one particle beam (120, 420, 720, 1315) and / or the particles (125) of the at least one other particle beam (120, 420, 1315); means for setting a flux density of the at least one particle beam (120, 420, 720, 1315) and / or the flux density of the at least one other particle beam (120, 420, 1315); or means for setting an irradiation time of the particles (125) of the at least one particle beam (120, 420, 720, 1315) and / or the particles (125) of the at least one other particle beam (120, 420, 1315).

27. 27. The device (1300) of any one of claims 23 to 26, further comprising at least one element of an electron flood gun (1303), an ion flood 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. 28. The device (1300) of any one of claims 23 to 27, further comprising means for displacing a point of incidence of the at least one particle beam (120, 420, 720, 1315) from the at least one first portion (630, 920, 1070) of the sample (100, 600, 1000, 1325) to the at least one second portion (150, 650, 1050) of the sample (100, 600, 1000, 1325).

29. 29. The device according to claim 23, further comprising means for performing a repair form at the at least one second location (150, 650, 1050) by means of the at least one other particle beam (120, 420, 1315), the means being further configured to irradiate the at least one first location (630, 920, 1070) with the at least one particle beam (720) to set the electrostatic charge (200, 300) of the sample (100, 600, 1000, 1325).

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