Method and apparatus for removing a particle from a photolithographic mask

Abstract

Method (3300) for removing a particle (550, 2750, 3150) from a photolithographic mask (500) by the following steps: a. Positioning (3320) a manipulator (300, 1300, 2500, 3000, 3100) movable relative to the mask (500) in the vicinity of the particle (550, 2750, 3150) to be removed; b. Connecting (3330) the manipulator (300, 1300, 2500, 3000, 3100) with the particle (550, 2750, 3150) by depositing a bonding material (730, 1730, 2440) on the manipulator (300, 1300, 2500, 3000, 3100) and / or the particle (550, 2750, 3150) from the gas phase; c. Removal (3340) of the particle (550, 2750, 3150) by moving the manipulator (300, 1300, 2500, 3000, 3100) relative to the photolithographic mask (500); and d. Separating the removed particle (550, 2750, 3150) from the manipulator (300, 1300, 2500, 3000, 3100) by performing a particle beam-induced etching process that removes at least a portion of the manipulator (300, 1300, 2500, 3000, 3100).

Description

1. Technical field

[0001] The present invention relates to a method and a device for removing a particle from a photolithographic mask. 2. State of the art

[0002] As a consequence of the increasing integration density in the semiconductor industry, photolithography masks must increasingly image smaller structures onto wafers. On the photolithography side, this trend toward increasing integration density is addressed by shifting the exposure wavelength of photolithography equipment to ever shorter wavelengths. Currently, photolithography or lithography equipment often uses an ArF (argon fluoride) excimer laser as the light source, emitting at a wavelength of approximately 193 nm.

[0003] Currently, lithography systems are under development that utilize electromagnetic radiation in the EUV (extreme ultraviolet) wavelength range (preferably in the 10 nm to 15 nm range). These EUV lithography systems are based on a completely new beam guidance concept that employs reflective optical elements, as no materials are currently available that are optically transparent in the specified EUV range. The technological challenges in developing EUV systems are enormous, and vast development efforts are required to bring these systems to industrial readiness.

[0004] Photolithographic masks, also known as exposure masks, photomasks, or simply masks, play a crucial role in imaging increasingly smaller structures in photoresist layers on wafers. With each increase in integration density, reducing the minimum feature size of the exposure masks becomes increasingly important. Consequently, the fabrication process for photolithographic masks becomes more complex, time-consuming, and ultimately more expensive. Due to the minuscule feature sizes of the pattern elements, errors during mask fabrication cannot be ruled out. These must be repaired whenever possible. Photomask repair involves removing portions of an absorber pattern that are present in areas of the mask not intended by the design.Furthermore, absorbing material is deposited at locations on the mask that are free of absorbing material, even though the mask design includes absorbing pattern elements. Both types of repair processes can generate debris or particles that can settle at transparent or reflective areas of photomasks and may be visible as imaging defects on a wafer.

[0005] More important, however, are dirt particles from the environment that settle on the surface of a mask. These are routinely removed from the surface through cleaning steps during mask manufacturing and during mask operation. Fig. Figure 1 shows a top view of a section of a photomask, which contains a particle located on a pattern element of the mask and which can be removed by a cleaning process. Furthermore, particles can be generated during the handling of a mask during its manufacturing process and / or operation, which can then settle on the mask.

[0006] The decreasing structural dimensions of photolithographic masks are making cleaning processes increasingly difficult. Furthermore, the decreasing exposure wavelength means that increasingly smaller foreign or dirt particles adsorbed on the mask surface become visible during exposure to a wafer. Fig. Figure 2 schematically shows a section of a mask in which two particles located in a contact hole of the photomask cannot be removed from the mask by means of a cleaning process.

[0007] Another method for removing particles from a photomask is to loosen or detach the particles from the mask's surface. This is often done using a micromanipulator or the probe tip of a scanning probe microscope. The particles are then removed in a second step through a cleaning process. Finally, a third step is required to verify that the particle(s) have indeed been removed from the mask.

[0008] The following are some examples of documents that investigate the manipulation of nanoparticles using a nano- or micromanipulator, such as the measuring tip of a scanning probe microscope: HH Pieper: “Morphology and electric potential of pristine and gold covered surfaces with fluorite structure”, Thesis, University of Osnabrück 2012; S. Darwich et al.: “Manipulation of gold colloidal nanoparticles with atomic force microscopy in dynamic mode: influence of particle-substrate chemistry and morphology, and operating conditions”, Beilstein J. Nanotechnol., Vol. 2 (2011), pp. 85–98; HH Pieper et al.: “Morphology and nanostructure of CeO2(111) surfaces of single crystals and Si(111) supported ceria films”, Phys. Chemistry Chemical Physics, Vol. 14, pp. 15361ff, 2013; E. Gallagher et al.: “EUVL mask repair: expanding options with nanomachining”, BACUS, Vol. 3, Issue 3 (2013), pp. 1-8; M. Martin et al.: „Manipulation of Ag nanoparticles utilizing noncontact atomic force microscopy“, Appl. Phys. Lett., Vol. 72, Nr. 11, Sept. 1998, S. 1505-1507; P.J. Durston et al.: „Manipulation of passivated gold clusters on graphite with the scanning tunneling microscope“, Appl. Phys. Lett., Vol. 72, Nr. 2, Jan. 1998, S. 176-178; R. Requicha: „Nanomanipulation with the atomic force microscope“, Nanotechnology Online, ISBN: 9783527628155; C. Baur et al.: „Nanoparticle manipulation by mechanical pushing: underlying phenomena and real-time monitoring“, Nanotechnology 9 (1998), S. 360-364; J.D. Beard et al.: „An atomic force microscope nanoscalpel for nanolithography and biological applications“, Nanotechnology 20 (2009), 445302, S. 1-10; US 6 812 460 B1.

[0009] In the article “Lifting and sorting of charged nanoparticles by electrostatic forces in atomic force microscopy”, small 2010, Vol. 6, No. 19, pp. 2105-2108, the authors J. Xu et al. report on the lifting of nanoparticles from a surface using a non-conductive measuring probe of an atomic force microscope, which has a metallic coating layer on the back, by applying a corresponding potential to the metallic coating layer.

[0010] US Patent 8,696,818 B2 describes a system for removing debris from the surface of a photolithographic mask. A probe tip of a scanning microscope is coated with a low surface energy material and moved across the mask surface. The debris physically adheres to the coated probe tip and is removed from the mask surface along with the probe tip.

[0011] In addition to the method described above, a particle that cannot be removed by a cleaning process can be removed using a local etching process. The difficulty with this approach lies in the fact that the composition of the particle to be removed is usually unknown. Therefore, the local etching process can only be partially, or not at all, tailored to the specific particle. Consequently, the local etching process is often lengthy and frequently unsuccessful. Moreover, as described above, a second measuring device must be used after the local etching process to verify whether the particle removal was successful.

[0012] German patent application DE 10 2016 203 094 A1 describes a method for permanently repairing defects of missing material in a photolithographic mask, comprising the steps of: (a) providing at least one carbon-containing precursor gas and at least one oxidizing agent at a location of the photolithographic mask to be repaired; (b) initiating a reaction of the at least one carbon-containing precursor gas with the aid of at least one energy source at the location of missing material to deposit material at the location of missing material, wherein the deposited material comprises at least one reaction product of the reacted at least one carbon-containing precursor gas; and (c) controlling a gas flow of the at least one oxidizing agent to minimize the carbon content of the deposited material.

[0013] German patent application DE 10 2017 205 629 A1 describes a method and a device for repairing at least one defect in a photolithographic mask for the extreme ultraviolet (EUV) wavelength range, wherein the method comprises the steps: (a) determining the at least one defect; and (b) determining a repair shape for the at least one defect; (c) wherein the repair shape is diffraction-based to take into account a phase disturbance caused by the at least one defect.

[0014] From a completely different technical field, namely the preparation of TEM (transmission electron microscope) samples, the in-situ lift-out method is known, in which a TEM sample is connected to a micromanipulator for transport purposes. The following documents, cited as examples, relate to the preparation of TEM samples: J. Mayer et al.: “TEM sample preparation and FIB-induced damage”, MRS Bulletin, Vol. 32, May 2007, pp. 400–407; B. Myers: “TEM Sample Preparation with the FIB / SEM”, Nuance Center, Northwestern University – Evanston, 2009; M. Schaffer et al.: “Sample preparation for atomic STEM at low voltages by FIB”, Ultramicroscopy, Vol. 114, pp. 62–71 (2012) and US 2017 / 0256380A1.

[0015] The multi-stage particle removal process described above is a lengthy (approximately four hours) and therefore costly process due to the sequential use of several different devices.

[0016] US patent application US 2010 / 0 186 768 A1 describes the deposition of material onto a particle so that the enlarged particle can be removed from the surface of a photolithographic mask by a cleaning process or by mechanical displacement with the measuring tip of an atomic force microscope.

[0017] The Japanese patent application JP 2005-084582 A describes the removal of a particle from a photomask using a dynamic or electromagnetic interaction or a chemical reaction between a probe of an atomic force microscope and the particle.

[0018] The present invention therefore addresses the problem of specifying methods and devices that make it possible to improve the removal of particles from photolithographic masks. 3. Summary of the invention

[0019] According to an embodiment of the present invention, this problem is solved by methods according to claims 1 and 5 and devices according to claims 14 and 16. In a first embodiment, a method for removing a particle from a photolithographic mask comprises the following steps: (a) positioning a manipulator movable relative to the mask in the vicinity of the particle to be removed; (b) connecting the manipulator to the particle by depositing a bonding material on the manipulator and / or the particle from the gas phase; (c) removing the particle by moving the manipulator relative to the photolithographic mask; and (d) separating the removed particle from the manipulator by performing a particle beam-induced etching process that removes at least a portion of the manipulator.

[0020] Performing a method according to the invention connects a manipulator with a particle to be removed. The particle can then be moved in a defined manner and thus removed from a photolithographic mask. The laborious and error-prone process of manually moving a particle with a micromanipulator is avoided. Furthermore, the time-consuming inspection of the photomask, which verifies whether the interfering particle has actually been removed, is eliminated. The manipulator is slightly modified during the separation process. However, this does not prevent a single manipulator from being used to remove multiple particles.

[0021] The deposition of the bonding material to connect the manipulator to the particle does not preclude the possibility of other interactions coupling the particle to the manipulator. These could include, for example, an electrostatic interaction and / or a van der Waals interaction between the manipulator and the particle.

[0022] The procedure may also include the step of depositing a sacrificial tip on the manipulator.

[0023] By depositing a sacrificial tip onto the manipulator, it can be used to remove many particles. If the sacrificial tip becomes unusable after a number of particle pickups, it can be removed from the manipulator, for example by a local etching process, and replaced by depositing a new sacrificial tip onto the manipulator.

[0024] The deposition of the sacrificial tip can involve the application of at least one of the following steps: a particle beam-induced deposition process and an electric field-induced deposition process.

[0025] A particle beam-induced deposition process can be induced by at least one element from the group: an electron beam, an ion beam, an atom beam, a molecular beam, and a photon beam.

[0026] By applying a suitable electrical voltage to a tip or measuring tip of a manipulator and providing a precursor gas, an electron-induced reaction can be triggered by field emission. The deposition of the sacrificial tip occurs primarily in the direction of the strongest electric field.

[0027] The manipulator may have a measuring tip for examining the photolithographic mask, and the procedure may further include the following step: depositing the sacrificial tip onto the measuring tip.

[0028] The method described above, using a measuring tip mounted on the manipulator, enables the first step of detecting a particle interfering with the image on the photomask. After depositing the sacrificial tip onto the manipulator, the second step allows for the removal of the interfering particle from the photolithographic mask. Both steps can be performed in a single device. This eliminates the need to transport the device to a second device and align the second device with the interfering particle to be removed.

[0029] Furthermore, depositing the sacrificial tip on the manipulator's measuring tip facilitates its deposition by field emission. Additionally, this increases the distance between the sacrificial tip and the manipulator, thus enabling the removal of particles from hard-to-reach areas of a photolithographic mask.

[0030] The sacrificial tip can have a length in the range of 5 nm to 5000 nm, preferably 10 nm to 2000 nm, more preferably 20 nm to 1000 nm, and most preferably 50 nm to 500 nm. The sacrificial tip can have a cylindrical shape with a diameter in the range of 1 nm to 1000 nm, preferably 2 nm to 500 nm, more preferably 5 nm to 200 nm, and most preferably 10 nm to 100 nm.

[0031] The sacrificial tip can be carbon-based. A precursor gas for depositing sacrificial tips can include at least one element from the following group: ethene, styrene, pyrene, hexadecane, liquid paraphines, formic acid, acrylic acid, propionic acid, methyl methacrylate.

[0032] A sacrificial tip can be electrically conductive. A precursor gas for depositing an electrically conductive sacrificial tip can comprise a metal carbonyl. A metal carbonyl can comprise at least one element from the group: chromium hexacarbonyl (Cr(CO)6), molybdenum hexacarbonyl (Mo(CO)6), tungsten hexacarbonyl (W(CO)6), dicobalt octocarbonyl (Co2(CO)8), triruthenium dodecarbonyl (Ru3(CO)6). 12 ), and iron pentacarbonyl (Fe(CO)5).

[0033] A sacrificial tip may have features that facilitate or simplify the removal of a particle from the tip. These features may include constrictions and / or markings indicating positions at which a particle beam-induced etching process can separate the particle and a portion of the sacrificial tip from the remaining main body.

[0034] In an alternative embodiment, a manipulator is provided which already has a sacrificial tip. In a first embodiment, the manipulator is replaced after the sacrificial tip has worn out. In a second embodiment, the worn sacrificial tip is removed from the manipulator and replaced by depositing a new sacrificial tip onto the manipulator.

[0035] The particle can have a diameter of 1 nm to 10 µm, preferably 5 nm to 5 µm, more preferably 10 nm to 2 µm, and most preferably 15 nm to 1 µm.

[0036] The positioned manipulator and the particle to be removed can be separated by a distance of 0 nm to 5000 nm, preferably 0 nm to 2000 nm, more preferably 0 nm to 1000 nm, and most preferably 0 nm to 500 nm.

[0037] According to a second embodiment, the method for removing a particle from a photolithographic mask comprises the following steps: (a) positioning a manipulator movable relative to the mask in the vicinity of the particle to be removed; (b) connecting the manipulator to the particle by depositing a bonding material onto the manipulator and / or the particle from the gas phase, whereby a particle beam inducing deposition is provided through the manipulator; and (c) removing the particle by moving the manipulator relative to the photolithographic mask.

[0038] In this embodiment, the particle beam inducing deposition does not need to be tilted from the normal direction with respect to the photomask. Furthermore, the manipulator in this embodiment does not require a tip and / or sacrificial tip. This eliminates the need to deposit a sacrificial tip on the manipulator.

[0039] The manipulator may have an opening, and / or a deposition-inducing particle beam may be provided through the opening of the manipulator. The deposition-inducing particle beam may, through the opening, induce the deposition of a sacrificial tip on the side of the manipulator facing away from the electron beam. The deposition-inducing particle beam may, through the opening, induce the deposition of the compound material.

[0040] An opening in a manipulator can thus be used in two different ways. Firstly, it facilitates the deposition of a sacrificial tip on the side of the manipulator opposite the impact of the inducing particle beam. Secondly, the opening of the manipulator can be used to align the manipulator relative to the particle and to connect the manipulator to the particle.

[0041] The bonding material can be deposited on at least one edge of the manipulator's opening.

[0042] The method of the second embodiment can further include the step of separating the removed particle from the manipulator by performing a particle beam-induced etching process in the area of ​​the bonding material. The particle beam-induced etching process can remove the bonding material between the manipulator and the particle.

[0043] This embodiment has the advantage that, after the removal of a particle, the manipulator remains essentially unchanged and available for further particle removal processes. Furthermore, the opening can be used to position or align the manipulator and the particle.

[0044] The opening can have any shape. Symmetrical openings, such as circular, triangular, rectangular, or square openings, are preferred. The diameter of the manipulator opening should be smaller than the diameter of the particle.

[0045] Step b of the inventive method may include: providing a precursor gas in the area of ​​the particle and the manipulator.

[0046] A precursor gas for the deposition of compound material can include at least one element from the group: ethene, styrene, pyrene, hexadecane, liquid paraphines, formic acid, acrylic acid, propionic acid, methyl methacrylate.

[0047] It is advantageous if the bonding material has a high carbon content. A high carbon content in the bonding material results in a hard bonding material. Carbon, or predominantly carbon-containing materials, can be easily etched using steam, thus enabling simple separation of the removed particle from the manipulator or the sacrificial tip of the manipulator. Furthermore, bonding materials that predominantly or at least partially contain carbon form volatile compounds when the bond between the sacrificial tip and particle, or between the manipulator and particle, is separated. These compounds, namely the carbon oxides CO₂ (carbon dioxide) and CO (carbon monoxide), can be easily removed from the reaction area.

[0048] The compound material can be electrically conductive. A precursor gas for depositing an electrically conductive compound material can comprise a metal carbonyl. A metal carbonyl can comprise at least one element from the group: chromium hexacarbonyl (Cr(CO)6), molybdenum hexacarbonyl (Mo(CO)6), tungsten hexacarbonyl (W(CO)6), dicobalt octocarbonyl (Co2(CO)8), triruthenium dodecarbonyl (Ru3(CO)6). 12 ), and iron pentacarbonyl (Fe(CO)5). The precursor gas diethylruthenocene (C₆H₆H₆) can be used to deposit ruthenium. 14 H 18 Ru) will be used.

[0049] Step b of the inventive method may include: providing a means in the area of ​​the particle and the manipulator for changing the precursor gas so that the compound material is deposited.

[0050] The device can include at least one of the following elements: a focused particle beam and an electric field between the particle and the manipulator.

[0051] The particle beams mentioned above in the context of sacrificial tip deposition can be used. An electron beam-induced deposition process has the advantage that the deposition reaction can be precisely localized. Moreover, an electron beam inducing a deposition process essentially does not damage the sample, i.e., the photomask, on which a disturbing particle is located.

[0052] The term “essentially” here means, as elsewhere in this application, a specification of a measurand within its error tolerances when the measurand is measured using instruments in accordance with the state of the art.

[0053] An electrical voltage can be applied to a conductive sacrificial tip of a manipulator between the sacrificial tip and the particle. By setting the electrical voltage, electrons emitted by field emission from the particle or the sacrificial tip can induce a local deposition reaction of a precursor gas between the sacrificial tip and the particle.

[0054] The bonding material can form a conditionally detachable or a non-detachable bond between the manipulator and the particle.

[0055] It is advantageous if the bonding material forms a conditionally detachable connection between the manipulator or the sacrificial tip of the manipulator and the particle. In this case, the manipulator can be used to successively remove a number of particles. However, it is also possible for the bonding material to create a permanent connection between the manipulator and the particle. In this case, the manipulator loaded with a particle is replaced with a new one.

[0056] To deposit the bonding material, the particle beam can pass through the manipulator.

[0057] The methods according to the invention of both embodiments can further include the step of analyzing a material of the removed particle.

[0058] A particle can only be examined to a very limited extent on a sample, such as a photomask. Firstly, particles are often located in hard-to-reach areas of the mask. Secondly, on-site analysis options are very limited, as the analysis of the particle should not alter the surrounding area of ​​the mask. Examining a particle using energy-dispersive X-ray spectroscopy (EDX) requires high kinetic energies of an electron beam, which can damage a mask. Furthermore, analyzing a particle directly on the mask would result in a large background in the EDX spectrum due to the particle's immediate surroundings, which would significantly distort the analysis of the particle through the surrounding mask.

[0059] A particular advantage of the methods described in this application is that the removed particle is not disposed of during a cleaning process and is therefore no longer available for analysis of its components. The methods defined above, on the other hand, allow the particle removed from the mask to be analyzed without the mask influencing the analysis result and without the mask being damaged by the particle analysis process.

[0060] The analysis of the particle often allows conclusions to be drawn about the particle-generating source, or at least the potential particle-supplying sources to be narrowed down. The methods according to the invention are therefore not merely repair methods for a photomask, but can help to eliminate particle formation and thus contribute to preventing the generation of contaminated or defective masks.

[0061] Analyzing the material of the removed particle may involve the use of at least one of the following measurement techniques: energy-dispersive X-ray spectroscopy, energy-dispersive X-ray absorption, wavelength-selective X-ray spectroscopy, secondary ion mass spectrometry, secondary neutral particle mass spectroscopy, Rutherford backscattering spectrometry, low-energy ion scattering spectroscopy.

[0062] In the context of the procedures described here, analytical methods that use an electron beam to excite a sample, i.e., a particle located away from a mask, can be advantageously employed. Typically, an electron beam is already available for depositing a sacrificial tip and / or for depositing the compound material onto the particle and / or the manipulator.

[0063] The sacrificial tip of the manipulator can be used to remove up to three, preferably up to five, more preferably up to eight, and most preferably up to twelve particles. The opening of the manipulator can be adapted to the size of a single particle. The opening of the manipulator can be used to remove up to ten, preferably up to twenty, more preferably up to forty, and most preferably up to one hundred particles.

[0064] Performing a particle beam-induced etching process can involve providing at least one etching gas to the bonding material. An etching gas can include water vapor (H₂O). An etching gas can include a halogen-containing gas, such as chlorine (Cl₂). An etching gas can include an oxygen-containing gas, for example, NO₂ (nitrogen dioxide). An etching gas can include xenon difluoride (XeF₂), xenon dichloride (XeCl₂), xenon tetrachloride (XeCl₄), XNO, XNO₂, XONO₂, X₂O, XO₂, X₂O₄, and X₂O₆, where X is a halogen, and nitrosyl chloride (NOCl).

[0065] Performing a particle beam-induced etching process can involve supplying at least one additional gas to the bonding material. This additional gas can include an oxidizing agent. The oxidizing agent can include at least one element from the following group: oxygen (O₂), ozone (O₃), water vapor (H₂O), hydrogen peroxide (H₂O₂), nitrous oxide (N₂O), nitrogen oxide (NO), nitrogen dioxide, and nitric acid (HNO₃).

[0066] In the second embodiment, separating the removed particle from the manipulator can include performing a cleaning process. This cleaning process can be a wet-chemical cleaning process. This embodiment has the disadvantage that the manipulator loaded with a particle typically has to be removed from its device for the cleaning process.

[0067] The method according to the invention can further include the step of depositing an auxiliary structure onto the particle.

[0068] Particles can be located at points on a mask where it is difficult to connect the particle to the manipulator or its sacrificial tip. Depositing an auxiliary structure on the particle makes the modified particle accessible to a particle removal method described in this application.

[0069] The auxiliary structure can be deposited using a particle beam-induced deposition process. This process can involve supplying a precursor gas to the particle. The precursor gases listed above in the context of depositing the sacrificial tip and the connecting material can be used for this purpose.

[0070] The deposition of the auxiliary structure may further include the step of thinning the auxiliary structure before connecting the manipulator to the auxiliary structure. Thinning the auxiliary structure may involve performing a particle beam-induced etching process. The particle beams and / or etching gases described above may be used to perform the particle beam-induced etching process for thinning the auxiliary structure.

[0071] The methods according to the invention may further include the step of compensating for an electrostatic charge during the deposition of the compound material using a charge compensation system.

[0072] The inventive method of the first embodiment can further include the step of compensating for an electrostatic charge during the deposition of the sacrificial layer using the charge compensation system.

[0073] By compensating for the electrostatic charge of the manipulator, the photomask and / or the particle, it is essentially possible to prevent the charged particle beam from being deflected incorrectly, thereby reducing the spatial resolution of a charged particle beam during a deposition process.

[0074] Positioning the manipulator with respect to the particle may also include determining a force acting between the manipulator or the sacrificial tip of the manipulator and the particle.

[0075] By measuring the interaction between the manipulator or the sacrificial tip of the manipulator and the particle, damage to the manipulator or its sacrificial tip, the particle and / or the photolithographic mask can be avoided when approaching the particle to position the manipulator near the particle to be removed.

[0076] Positioning the manipulator can involve performing a relative movement between the manipulator and the particle by moving the manipulator, by moving the photolithographic mask, or by a combined movement of the manipulator and the photolithographic mask.

[0077] The manipulator can include a cantilever. The cantilever can have a mounting plate at one end for attaching it to a scanning probe microscope. The sacrificial tip can be deposited on the end of the cantilever opposite the mounting plate. The cantilever can include a measuring tip for examining the photolithographic mask onto which the sacrificial tip is deposited. The cantilever can have an opening at the end opposite the mounting plate.

[0078] The manipulator can include an optical light pointer system in addition to the cantilever. The deflection of the cantilever, and thus the force acting between the manipulator or the sacrificial tip of the manipulator and the particle, can be determined using the optical light pointer system.

[0079] In a first embodiment, the device for removing a particle from a photolithographic mask comprises: (a) a manipulator movable relative to the mask, which can be moved into the vicinity of the particle to be removed; (b) a deposition device configured to deposit a bonding material onto the manipulator and / or the particle from the gas phase in order to bond the manipulator to the particle; and (c) a separation device configured to separate the removed particle from the manipulator by performing a particle beam-induced etching process that removes at least a portion of the manipulator.

[0080] The manipulator can include a sacrificial tip and / or the particle beam-induced etching process can remove at least a portion of the sacrificial tip of the manipulator.

[0081] The device may include a modified scanning particle microscope and / or at least one scanning probe microscope. The device may include a modified scanning particle microscope and / or a manipulator device. The manipulator device may include a mount for a manipulator, a positioning system, and a control unit.

[0082] A modified scanning particle microscope or a modified scanning particle beam microscope can include at least one element from the following group: a modified scanning electron microscope, a modified scanning ion microscope, and a modified optical microscope. A scanning probe microscope can include at least one element from the following group: an atomic force microscope, a magnetic force microscope, an acoustic near-field scanning microscope, and an optical near-field scanning microscope.

[0083] The device can comprise a modified scanning electron microscope and at least one atomic force microscope. The device can also comprise a modified scanning electron microscope and at least one manipulator device.

[0084] The manipulator can be coupled to the scanning probe microscope. The manipulator can be coupled to the manipulator device. The manipulator can include a cantilever. The cantilever can include a mounting plate at one end for attaching the cantilever to the scanning probe microscope. A sacrificial tip of the manipulator can be deposited onto the end of the cantilever opposite the mounting plate. The cantilever can include a measuring tip onto which the sacrificial tip is deposited.

[0085] The manipulator can include a probe array. The probe array can be one-dimensional or two-dimensional. The probe array can include at least two cantilevers. A first cantilever can include a measuring tip for examining the photolithographic mask. At least one second cantilever can include a sacrificial tip and / or an opening for connecting to the particle. The second cantilever can include multiple cantilevers, each connecting to a particle to be removed. Each cantilever of the probe array can be individually controlled by a control unit of the device. However, it is also possible for a probe array to include probes with sacrificial tips that serve both as measuring tips for analyzing a sample, i.e., an element for photolithography, and for removing particles.

[0086] The device of the first embodiment can be configured to tilt the manipulator against the normal direction of the photolithographic mask.

[0087] Tilting the sacrificial tip of the manipulator against the normal direction of the photolithographic mask prevents the manipulator from completely or partially obscuring the particle beam inducing deposition, thereby facilitating the provision of a particle beam in the area of ​​the particle for depositing the compound material.

[0088] The manipulator and / or the measuring tip of the manipulator may have an incline so that a particle beam incident substantially in the normal direction to the photolithographic mask can image the tip of the measuring tip and / or the tip of the sacrificial tip.

[0089] Angled manipulators and, if applicable, their measuring tip prevent the manipulator or its measuring tip and / or the particle beam from tilting against the normal direction of the photolithographic mask.

[0090] The device can include one or more displacement elements configured to perform a relative movement between the manipulator and the photolithographic mask in three spatial directions.

[0091] The deposition device can further be configured to deposit a sacrificial tip onto the manipulator. In this embodiment, the device can be used not only to remove the particle from the photomask but also to deposit a sacrificial tip onto the manipulator or onto the manipulator's measuring tip. Because the device can replace a worn measuring tip within itself, the interval between manipulator replacements can be extended. This reduces the device's downtime.

[0092] In a second embodiment, the device for removing a particle from a photolithographic mask comprises: (a) a manipulator movable relative to the mask, which can be moved into the vicinity of the particle to be removed; (b) and a deposition device configured to deposit a bonding material onto the manipulator and / or the particle from the gas phase in order to bond the manipulator to the particle, the deposition device further configured to provide a particle beam through the manipulator to induce deposition.

[0093] The device of the second embodiment can include a separating device designed to separate the removed particle from the manipulator.

[0094] The device may include a detector for detecting X-ray radiation.

[0095] In combination with a particle beam that excites the particle located away from the photolithographic mask, the detector can be used to determine the particle's material composition. For example, an electron beam can be used to excite the particle. Specifically, an electron beam can be directed at the particle to generate characteristic X-ray radiation from the particle.

[0096] The separation device can be configured to provide at least one etching gas and at least one particle beam in the area of ​​the joining material.

[0097] The device may include a gas storage system for storing one or more precursor gases, one or more etching gases, and an additive or additional gas. The device may further include at least one gas supply system and / or a gas metering system.

[0098] The photolithographic mask can include a pattern-bearing element of a photolithographic exposure process. The pattern-bearing element of the photolithographic exposure process can include at least one element from the following group: a photolithographic mask, a template for nanoimprint lithography, and a wafer. The photolithographic mask can be either reflective or transmitting.

[0099] The devices of the first and / or second embodiment can include a magazine containing a supply of manipulators. Furthermore, the devices of the first and second embodiments can include a container for worn or used manipulators. The devices can be configured to automatically change the manipulators. This means that the devices can deposit a useless manipulator into the designated container and take a new manipulator from the magazine. These aspects are particularly advantageous for devices of the first embodiment. The sacrificial tips can be used to remove multiple particles; however, they become shorter due to the etching of part of the sacrificial tip when the particle is separated from it, and thus are eventually worn out during their use.

[0100] The devices of the first and / or the second embodiment may include a control device configured to execute the process steps of the methods of the first and second embodiments explained above according to the invention.

[0101] A computer program may include instructions which, when executed by a computer system, cause the device of the first embodiment according to the invention to perform the process steps according to the method of the first embodiment according to the invention.

[0102] Finally, a computer program can include instructions which, when executed by a computer system, cause the device of the second embodiment according to the invention to perform the process steps according to the method of the first embodiment according to the invention. 4. Description of the drawings

[0103] In the following detailed description, currently preferred embodiments of the invention are described with reference to the drawings, wherein Fig. Figure 1 schematically shows a section of a top view of a photolithographic mask on which a particle is present that can be removed by means of a cleaning process; Fig. 2 schematically presents a section of a top view of a photolithographic mask on which two particles are present that cannot be removed by a cleaning process; Fig. Figure 3 schematically shows an example of a manipulator in the form of a cantilever, a measuring tip, a holding plate and a mount of a manipulator device or a scanning probe microscope; Fig. 4 schematically depicts a deposition process of a sacrificial tip onto the measuring tip of the manipulator. Fig. 3 presents; Fig. 5 shows a schematic section through a photolithographic mask, wherein the substrate of the photomask has a defect in the form of a particle; Fig. 6 the mask of Fig. 5 illustrated after the sacrificial tip of a manipulator approaches the particle of the photomask; Fig. 7 the configuration of Fig. 6 during the deposition of a compound material onto the sacrificial tip and the particle using a particle beam-induced deposition process; Fig. Figure 8 schematically presents the removal of the particle connected to the sacrificial tip of the manipulator; Fig. 9a schematically illustrates in a first example the separation of the particle from a sacrificial tip by performing a particle beam-induced local etching process; Fig. 9b the peak of the victims Fig. 9a after the particle has been separated; Fig. 10 In a second example, the separation of the particle from a sacrificial tip by performing a particle beam-induced local etching process is schematically illustrated; Fig. Figure 11 shows a schematic section through a device for depositing a sacrificial tip by field emission; Fig. 12 represents a sacrificial tip deposited on a measuring tip by field emission; Fig. 13 presents a schematic section through a cantilever with a measuring tip, wherein the cantilever and the measuring tip are beveled; Fig. 14 shows a second example of a manipulator, wherein the cantilever of the manipulator has an opening on the side facing away from the mounting plate; Fig. Figure 15 shows a schematic section through a photomask in the region of a particle, wherein the opening of the manipulator of the Fig. 14 is positioned above the particle; Fig. 16 schematically an arrangement for depositing compound material onto the edges of the manipulator opening and the particle of the Fig. 15 presented; Fig. 17 the Fig. Figure 14 shows the deposited compound material and the lifting of the particle. Fig. 15 by moving the manipulator of the Fig. 14 and / or the photolithographic mask of the Fig. 15 illustrated; Fig. Figure 18 represents a particle located in a gap between two pattern elements of a photomask and schematically illustrates the deposition of an auxiliary structure onto the particle of diagram 1800. Fig. 18 represents; Fig. 19 the lower part of the Fig. 18 (Diagram 1850) reproduced, with a sacrificial tip positioned near the auxiliary structure deposited on the particle; Fig. Figure 20 in the upper part of the diagram (Diagram 2000) shows a small particle that is arranged between two linear pattern elements, and in the lower part of the diagram (Diagram 2050) shows a second example of an auxiliary structure that has been deposited on the particle; Fig. 21 in the upper part of the diagram (diagram 2100), the lower part of the diagram Fig. Figure 20 (Diagram 2050) shows the auxiliary structure after it has been thinned by performing a particle beam-induced etching process, and the lower part of the diagram (Diagram 2150) shows the insertion of the thinned auxiliary structure into the opening of the cantilever of the manipulator. Fig. 14 represents; Fig. 22 in the upper part of the diagram (diagram 2200), the lower part of the diagram Fig. 21 (Diagram 2150) illustrates the deposition of bonding material onto the edges of the cantilever opening and the modified auxiliary structure, and the lower part of the diagram (Diagram 2250) illustrates the lifting of the particle from the photomask substrate; Fig. Figure 23 in the upper part of the diagram (Diagram 2305) schematically shows the deposition of compound material onto a particle to be removed by means of a particle beam-induced deposition process, wherein the particle beam passes through the cantilever of the manipulator, and in the lower part of the diagram (Diagram 2355) schematically illustrates trajectories of secondary electrons in the cantilever and between the cantilever and the particle or the substrate of the mask; Fig. 24 in the upper part of the diagram (diagram 2400) presents a schematic section through the lower part of the diagram (diagram 2355) after completion of the deposition of the bonding material between the particle and the cantilever, and in the lower part of the diagram (diagram 2450) shows the lifting of the particle from the photomask; Fig. 25 in the upper part of the diagram (diagram 2505) shows a manipulator with a holding plate to which three cantilevers are attached, in the middle part of the diagram (diagram 2545) shows the positioning of one of the cantilevers of the manipulator of the upper part of the diagram over a particle, and the lower part of the diagram (diagram 2575) presents the joining of the particle to the cantilever positioned above it by depositing connecting material; Fig. 26 in the upper part of the image (diagram 2600) represents the removal of the particle connected to a cantilever after performing a relative movement between the mask and the manipulator, and in the lower part of the image 2650 represents the bending away of the cantilever loaded with the particle from the photolithographic mask; Fig. 27 in the upper part of the image (diagram 2700) shows a vertical section of the positioning of a second cantilever of the manipulator. Fig. 25 shows above a second particle, and the lower part of the image (diagram 2750) shows a schematic perspective representation of diagram 2700; Fig. 28 in the upper part of the image (diagram 2800) the alignment of a cantilever of the manipulator of the Fig. 25 above a particle, in the middle part of the diagram (diagram 2835) showing the lowering of the aligned cantilever onto or near the particle, and in the lower part of the diagram (diagram 2870) showing the connection of the lowered cantilever to the particle; Fig. Figure 29 in the upper part of the diagram (Diagram 2900) shows the lifting of the particle and the reversal of the bending of the cantilever connected to the particle; the lower part of the diagram (Diagram 2950) shows the lowering of a second cantilever of the manipulator. Fig. 25 represents a particle aligned with respect to a second cantilever; Fig. 30 presents a schematic top view of another example of a manipulator comprising a two-dimensional arrangement of cantilevers; Fig. Figure 31 shows a section through a curved manipulator comprising a 7×7 cantilever arrangement, wherein in the upper part of the diagram (Diagram 3100) the middle cantilever is positioned over a first particle, in the middle part of the diagram (Diagram 3135) the middle cantilever has picked up the first particle and the second-left cantilever of the manipulator is aligned over a second particle, and in the lower part of the diagram (Diagram 3170) the second-left cantilever has picked up the second particle and the second-right cantilever is aligned with respect to a third particle; Fig. 32 shows a schematic section through a device with which one of the described methods can be carried out; Fig. 33 shows a flowchart of a first embodiment of the method according to the invention; and Fig. 34 Finally, a flowchart of a second performance form of the method according to the invention is presented. 5. Detailed description of preferred embodiments

[0104] In the following, currently preferred embodiments of the methods and devices according to the invention for removing a particle from a photolithographic mask are explained in more detail. However, the methods and devices according to the invention are not limited to the examples discussed below. Rather, they can generally be used for removing particles from pattern-bearing elements used in a photolithography process. Examples of these elements include photomasks, templates used in nanoimprint lithography, and wafers to be processed.

[0105] The Fig. Figure 1 shows a top view of a section of a photolithographic mask 100. The section of the photolithographic mask 100 presents a substrate 110 on which three pattern elements 120, 130, 140 of absorbing material are arranged in the form of vertical stripes. Due to the location of the particle 150 on the pattern element 130, which typically has a height of 50 nm to 200 nm, the particle 150 can be removed from the photomask 100 by means of a cleaning process.

[0106] The Fig. Figure 2 also shows a section of a top view of a photolithographic mask 200. The exemplary mask 200 has a substrate 110. Six contact holes 220 are formed in two rows in the substrate 110 of the mask 200. A particle 250 is present in a substantially central position in the middle contact hole 220 of the upper row. In the lower row, a particle 260 is located at the upper edge of the middle contact hole 220. A contact hole 220 typically has a depth in the range of 50 nm to 200 nm. Neither particle 250 nor 260 can be removed from the mask 200 by a cleaning process. In addition to the particles 250, 260, which are present in a recess of a photomask, particles that are adsorbed at the edge of a pattern element 120, 130, 140 and especially in corners of a pattern element cannot be removed from the mask 100, 200 by means of a cleaning process or can only be removed very poorly.The following description of particle removal from photomasks refers to particles 250, 260, which cannot be removed from a photomask 200 by means of a cleaning process.

[0107] In the Fig. Figure 3 schematically depicts a manipulator 300. The exemplary manipulator comprises a bending beam 310, a spring beam 310, or a lever arm 310. The bending beam 310 will be referred to as the cantilever 310 in the following text, as is customary in the field. The cantilever 310 of the manipulator 300 has a measuring tip 320 at one end (the free end). In the example of the Fig. The measuring tip 320 has an elongated, thin tip with a small radius of curvature, suitable for analyzing a sample surface, such as the mask 100, 200. (The terms sample and photomask are used synonymously below.) At the end opposite the measuring tip 320 or the free end, the cantilever 310 of the manipulator 300 has a mounting area 330, which is also referred to below as the mounting plate 330 or mounting element 330. Furthermore, the manipulator 300 has a support element 340. The cantilever 310 and the mounting element 330 are often made from a single piece of single-crystal silicon. Typically, the support element 340 is glued to the mounting plate 330 of the manipulator 300. With the aid of the carrier element 340, the manipulator 300 can be installed in a measuring head of a scanning probe microscope or a head of a manipulator device (in the Fig. 3 not shown).

[0108] The cantilever 310 of the manipulator 300 can be moved by a movement of the mount 340 by a measuring head of a scanning probe microscope or the head of a manipulator device. In particular, the cantilever 310 can be excited to vibrate. For this purpose, the support element 340 of the manipulator 300 can be connected to a piezoelectric element, which can excite the cantilever 310 to vibrate, for example, at the resonance frequency of the manipulator 300 (in the Fig. 3 (also not shown). Furthermore, it is possible to excite the manipulator 300 or its cantilever 310 to oscillation using a laser beam. An oscillation mode of the cantilever 310 can be used while the measuring tip 320 approaches the surface of the photomask 200 and / or for scanning the mask 200 in the area of ​​the particle 250, 260.

[0109] The Cantilever 310 can have a bimorphic structure, i.e., it comprises two superimposed, interconnected layers that have different coefficients of thermal expansion (in the Fig. 3 not shown). By depositing energy into the cantilever 310, it can be bent towards or away from the sample surface, depending on the embodiment. Energy can be introduced locally into the cantilever 310, for example, by irradiating it with a laser beam or an electron beam. Furthermore, it is possible to attach a heating resistor to the cantilever 310 in order to bend it towards or away from the sample surface by local heating (in the Fig. 3 not shown).

[0110] The Cantilever 310 can have an actuator in the form of a piezo actuator (in the Fig. (Figure 3 not shown). The piezo actuator can deflect the cantilever 310. In particular, the piezo actuator can bend the measuring tip 320 towards a sample surface. Furthermore, the piezo actuator can excite the cantilever 310 of the manipulator 300 to vibrate. Preferably, a piezo actuator excites the cantilever 310 at or near a resonance frequency of the manipulator 300. In a preferred alternative embodiment, a piezo actuator is mounted in the region of the support element 340 and connects the manipulator 300 to a measuring head of a scanning probe microscope or a head of a manipulator device. In the latter embodiment, the cantilever 310 can include a resistive element that can be used to bend the cantilever 310 towards or away from the surface of the mask. The above-described device with a piezo actuator integrated into the spring beam 310 uses the inverse piezoelectric effect.

[0111] Furthermore, it is possible to deflect the cantilever 310 due to electrostatic forces and / or based on the inverse piezoelectric effect. In addition, magnetic fields (magnetostriction) can be used to bend the cantilever 310 towards or away from the sample surface. A disadvantage of this embodiment is the typically high sensitivity of scanning particle microscopes, especially scanning electron microscopes, to electric and magnetic fields.

[0112] The surface of the cantilever 310 of the manipulator 300, which faces the measuring tip 320, can be provided with a thin metallic reflective layer to increase the reflectivity of the surface of the cantilever 310 for a light beam acting as a light pointer (in the Fig. (3 not shown). Using the light pointer system, the approach of the manipulator to the photomask 200 can be indirectly tracked via an interaction of the measuring tip 310 with a sample surface. Furthermore, the light pointer system can be used during the operation of the manipulator 300 to determine the interaction between the measuring tip 320 and the photomask 200, or between the measuring tip 320 and the particles 250, 260.

[0113] In the following Fig. 4, Fig. 5, Fig. 6, Fig. 7, Fig. 8, Fig. 9 to Fig. Section 10 describes a first embodiment of removing a particle from a photomask. The process begins in diagram 400. Fig. 4 by depositing a sacrificial tip 450 onto the measuring tip 320 of the manipulator 300. The depositing is carried out in the Fig. The example shown in Figure 4 is carried out using a particle beam-induced deposition process. Fig. In figure 4, the measuring tip 320 is perpendicular to the particle beam 410, which is represented as an electron beam 410 in diagram 400. This requires either rotating the measuring tip 320 of the manipulator 300 by 90° or rotating the electron beam 410 by 90°. It is also possible for the electron beam 410 and the manipulator 300 to perform a combined movement, such that the measuring tip 320 of the manipulator 300 is essentially perpendicular to the axis of the electron beam 410. In the example of the Fig. In section 4, the measuring tip 320 is rotated by 90° relative to its usual operating direction. The electron beam 410 is focused on the tip of the measuring tip 320. A precursor gas 420 is provided at the point where the electron beam 410 strikes the measuring tip 320. This is in the Fig. 4 indicated by the dashed arrows 420. In the Fig. In the example presented, the precursor gas 420 is styrene (C8H8). Styrene has a high carbon content, so the sacrificial tip 450 consists mainly of carbon. If a conductive sacrificial tip 450 is to be deposited, the metal carbonyl dicobalt octocarbonyl (CO2(CO)8) can be used as the precursor gas 420 (in the Fig. 4 not shown).

[0114] The deposition process begins at the measuring tip 320 (symbolized by arrow 460) and proceeds along the direction 430 indicated by arrow 430, ending with a sacrificial tip length 450, indicated by arrow 470. In the Fig. In the example shown in Figure 4, a substantially cylindrical sacrificial tip 450 with a tip 480 in the form of an elliptical paraboloid of revolution is deposited. The electron beam for depositing the sacrificial tip 450 covers an energy range from 100 eV to 50 keV; currently preferred values ​​are in the range of 5 keV. The current of the electron beam covers a range from 1 pA to 50 nA. Currents in the range of 20 pA are currently frequently used.

[0115] In an alternative embodiment, the measuring tip 320 of the manipulator 300 already has a sacrificial tip 450, and the process of depositing the sacrificial tip 450 can be avoided. Furthermore, it is possible that the manipulator 300 has a worn sacrificial tip before a particle removal process is carried out. In this case, either the manipulator 300 is replaced with a new manipulator 300 with a sacrificial tip 450, or the worn sacrificial tip is removed from the manipulator 300, for example, by performing a particle beam-induced etching process, and a new sacrificial layer 450 is deposited on the measuring tip 320 of the manipulator 300 as described above.

[0116] The Fig. Figure 5 shows a schematic section through a photomask 500. The photolithographic mask 500 has a transmitting substrate 510 with absorbing pattern elements 520. A particle 550 is present on the substrate 510 near the left pattern element 520. Due to its location near a pattern element 520, the particle 550 cannot be removed from the photomask 500 by a cleaning process, or only with great difficulty.

[0117] As stated above, in the Fig. 5. The mask 500 is a transmitting photomask. However, the procedures described below for removing particle 550 can also be applied to reflective masks.

[0118] Diagram 600 of the Fig. 6 represents the mask 500 of the Fig. 5 after the tip 480 of the sacrificial tip 450 of the manipulator 300 was positioned near the particle 550. The distance between the particle 550 and the tip 480 of the sacrificial tip 450 is, in the example of the Fig. 6 approximately 50 nm. Currently, it is preferred to bring the tip 480 of the sacrificial tip 450 into mechanical contact with the particle 550.

[0119] Diagram 700 of the Fig. Figure 7 shows the deposition process of bonding material 730 onto particle 550 and the sacrificial tip 450 of the manipulator 300 for bonding particle 550 and sacrificial tip 450. The in the Fig. The deposition process shown in Figure 7 comprises a particle beam-induced deposition process. For this purpose, an electron beam 710 is used as the particle beam 710. The kinetic energy of the electron beam 710 for depositing the compound material 730 is in the range of 100 eV to 50 keV; currently, electron energies in the range of 5 keV are preferably used. The current of the beam current is in the range of 1 pA to 50 nA; currently, currents in the range of 20 pA are used. Furthermore, a precursor gas 720 is provided in the region of the particle. This is illustrated by the dashed arrow. The precursor gas 720 is [missing information]. Fig. The exemplary deposition process shown in Figure 7 is used for compound material 730 styrene (C8H8). As already explained above, the precursor gas styrene has a high carbon content, so compound material 730 also has a high carbon content.

[0120] Diagram 800 of the Fig. Figure 8 illustrates the removal of particle 550, connected to the sacrificial tip 450, from the substrate 510 of the photomask 500. The removal of particle 550 from substrate 510 is shown in the Fig. 8 is symbolized by the arrow 810. In the example of the Fig. 8. The manipulator 300, which carries the sacrificial tip 450, is moved away from the photomask 500 in a normal direction. Alternatively, the photomask 500, which is typically arranged on a stage, can be lowered (in the Fig. 8 not shown). A combined movement of the sacrificial tip 450 and the photolithographic mask 500 is also possible.

[0121] After particle 550 detaches from substrate 500, the particle 550 coupled to the tip 480 of the sacrificial tip 450 can be analyzed. For this purpose, the sacrificial tip 450 is moved into a position where it can be irradiated, for example, with the particle beam 710, without the particle beam 410, such as an electron beam 410, being able to damage the photomask 500 (in the Fig. (Figure 8 not shown). For example, the radiation emitted by the electron beam 710 of the excited particle 550 can be analyzed using an X-ray detector. The material composition of particle 550 can be determined from the detector's measurement data.

[0122] Diagram 900 of the Fig. Figure 9a schematically shows the separation of the removed particle 550 from the tip 480 of the sacrificial tip 450, which is carried out, if necessary, after completion of the analysis process of particle 550. The separation is performed in the example of... Fig. 9a by performing an electron beam induced etching process (EBIE). In the Fig. The example shown in 9a shows the peak victim count of 450 – as in the context of the Fig. 9a is carried out – with carbon as the main component. Near the tip 480 of the sacrificial tip 450, the etching gas 920 (water vapor) is supplied. Simultaneously, a focused electron beam 910 excites or splits the etching gas 920. If necessary, an additive or supplementary gas can be supplied to the reaction site in addition to the etching gas 920 to support the local etching process. An additive gas could, for example, be an oxidizing agent such as oxygen (O2) and / or chlorine (Cl2).

[0123] Diagram 990 of the Fig. Figure 9b shows the modified sacrificial tip 950 after the separation process from the particle 550 is complete. The tip 980 of the modified sacrificial tip 950 has a different shape than the unused sacrificial tip 450. Despite the modified tip 980, the modified sacrificial tip 950 can be used to remove further particles 550 from the photomask 500. Depending on the length and material composition of the sacrificial tip 450, as well as the execution of the separation process of the particle 550 associated with the sacrificial tip 450, a sacrificial tip 450 can typically be used to remove five to ten particles 550. The sacrificial tip 450 may have one or more markings and / or constrictions that facilitate the removal of the particle from the sacrificial tip 450.

[0124] If the sacrificial tip 450 is made electrically conductive, for example by using a metal carbonyl in its manufacture, the etching gas to be used is selected depending on the material of the sacrificial tip. If, for example, chromium hexacarbonyl (Cr(CO)6) is used as the precursor gas, a mixture of xenon difluoride (XeF2), water vapor, and nitrosyl chloride (NOCl) can be used as the etching gas to separate a particle 550 from the sacrificial tip 450.

[0125] Diagram 1000 of the Fig. Figure 10 presents a sacrificial tip 1050, the material of which is not, or only very poorly, etchable by steam, such as a sacrificial tip 1050 made of quartz. If, in addition, the connecting material 730 is readily etchable by steam, for example, because its main component is carbon, an electron beam-induced etching process can remove the particle 550 from the tip 1080 of the sacrificial tip 1050 without substantially altering the tip 1080 of the sacrificial tip 1050. The electron beam-induced etching process is described in the Fig. 10 is symbolized by the electron beam 910 and the etching gas 1020.

[0126] In an alternative embodiment, the particle 550 is directly connected to the measuring tip 320 of the manipulator 300 without depositing a sacrificial layer 450 onto the measuring tip 320. The particle 550 is separated from the measuring tip of the manipulator by means of an EBIE (Electron Beam Induced Etching) process, as described in the preceding section. This embodiment has the advantage of avoiding the deposition of a sacrificial tip 450.

[0127] The Fig. Figure 11 shows a schematic section through a device 1100 for depositing a sacrificial tip 450 onto the measuring tip 320 of a manipulator 300 by means of field emission. The device 1100 represents an alternative to the method described in the context of Fig. Figure 4 describes the particle beam-induced deposition process of a sacrificial tip 450. The manipulator 300 with the measuring tip 320 is mounted on piezo actuators 1140. These enable the positioning of the measuring tip 320 above the electrode 1190, which is located in a housing 1130 that is electrically insulated from the environment. The electrode 1190 is mounted on a sample holder 1120 of a scanning electron microscope 1110. The scanning electron microscope 1110 serves both to align the measuring tip 320 with the electrode 1190 and to image the deposited sacrificial tip. In detail, the reference numeral 1110 designates both the scanning electron microscope 1110 and the exit lens 1110 of the scanning electron microscope 1110. A precursor gas is supplied between the measuring tip 320 and the electrode 1190 via the gas inlet 1150. One of the metal carbonyls listed above, for example, can be used as the precursor gas.

[0128] An electric field 1190 is generated between the measuring tip 320 of the manipulator 300 and the electrode via the electrical connections 1160 and 1180. The electric field has the highest field strength (>10 9 V / m) at the tip of the measuring probe 320. In this region, field emission causes an electron flow with high local density, sufficient to excite the precursor gas 1150, so that a sacrificial probe 1250 is deposited on the measuring probe 320 of the manipulator 300. Diagram 1200 of the Fig. Figure 12 shows a scanning electron microscope image 1110 of the sacrificial tip 1250 on the measuring tip 320. The sacrificial tip 1250 grows essentially in the direction of the gradient of the electric field.

[0129] As in the Fig. As illustrated in Figure 7, in the first embodiment described above, the sacrificial tip 450 is inclined relative to the normal direction or the direction of incidence of the particle beam 710 so that the particle beam 710 is not shadowed during the deposition of the compound material 730 between the particle 550 and the tip 480 of the sacrificial tip 450. As a second example, the Fig. Figure 13 represents a manipulator 1300 which does not need to be inclined or tilted against the direction of incidence of the particle beam 710 to remove the particle 550. The cantilever 1310 and the measuring tip 1320 of the manipulator 1300 are inclined such that, with the cantilever 1310 horizontal, a particle beam 710 can image the tip 1330 of the measuring tip 1320. Even after depositing a sacrificial tip 450, 1250 onto the tip 1330 of the measuring tip 1320, the beam direction of the particle beam 710 and the orientation of a sacrificial tip 450, 1250 can be essentially parallel to each other if the sacrificial tip 450 has a similarly inclined arrangement to the measuring tip 1320.

[0130] Based on the Fig. 14, Fig. 15, Fig. 16 to Fig. In section 17, a second embodiment for removing a particle 550 from a photomask 500 is presented. As a third example, the Fig. Figure 14 schematically shows a manipulator 1400 comprising a cantilever 1410 and a mounting plate 1430. The support elements of the manipulator 1400 are shown in the Fig. 14 suppressed. This also applies to the subsequent manipulators. Instead of a measuring tip 320, 1320, the cantilever 1410 has an opening 1420 at its free end, i.e., the end opposite the retaining plate 1430. The opening 1420 can have any shape. In the Fig. In the example shown in Figure 14, the aperture 1420 is square with a side length of approximately 50 nm. The manipulator 1400 is arranged above the photomask 500, which contains the particle 550 that is in the Fig. 14 is not shown.

[0131] The Fig. Figure 15 schematically shows a section through the substrate 510 of the photolithographic mask 500 in the area of ​​particle 550. The opening 1420 of the cantilever 1410 is positioned above particle 550. In the Fig. In the example shown, the edges of the opening 1420 are at least partially in contact with the particle 550. However, it is also possible that the edges of the opening 1420 have a distance from the particle 550 of up to the three-digit nanometer range. The greater the distance between the edges of the opening 1420 and the particle 550, the more bonding material must be deposited to connect the manipulator 1400 to the particle. From a distance of approximately 1 µm, the particle removal process becomes uneconomical.

[0132] The Fig. Figure 16 schematically shows the connection of the cantilever 1410 to the particle 550 by depositing connecting material using a particle beam-induced deposition process. For this purpose, a gas supply system 1630 provides a precursor gas 1620 in the region of the particle 550. A particle beam 1610, which in this example is Fig. 16 an electron beam 1610 of a scanning electron microscope 1640 excites the precursor gas 1620, causing it to deposit the compound material.

[0133] Diagram 1700 of the Fig. 17 gives the Fig. 15 again, after the bonding material 1730 was deposited on particle 550 and at the edges of the opening 1420 of the cantilever 1410 of the manipulator 1400. Diagram 1760 of the Fig. Figure 17 presents a configuration after the particle 550 was removed from the substrate 510 of the mask 500 by a relative movement between the manipulator 1400 and the mask 500.

[0134] In the Fig. 18 and Fig. Section 19 describes a modification of the first embodiment for the case where the particle 550 is located at a point where the measuring tip 320, 1320, or the sacrificial tip 450 of the manipulator 300 cannot be brought, or at least not safely. Diagram 1800 of the Fig. Figure 18 presents a photomask 500 whose pattern elements 520 leave only a narrow slit with a small width to the substrate 510 of the mask 500. A small particle 550 is present on the substrate 510 in this slit. Inserting the sacrificial tip 450 into the slit to position it near the particle 550 could damage one or more of the pattern elements 520 and / or the sacrificial tip itself.

[0135] The diagram from 1850 of the Fig. Figure 18 schematically presents the solution to this problem. An auxiliary structure 1840 is deposited onto particle 550 using a particle beam-induced deposition process, such that particle 550, including the deposited auxiliary structure 1840, protrudes for the pattern elements 520. In the example shown in diagram 1850, a precursor gas 1820, symbolized by the arrow near particle 550, is provided for depositing the auxiliary structure 1840 onto particle 550. If an electrically conductive connection between particle 550 and sacrificial tip 450 is to be established, a metal carbonyl, such as dicobalt octocarbonyl (CO2(CO)8), can be used for the precursor gas 1820. If an electrically conductive connection between the particle 550 and the sacrificial tip 450 is not required, a carbon-containing precursor gas 1820, such as styrene, can be used.

[0136] The diagram from 1900 of the Fig. Figure 19 demonstrates that the victim peak 450, 1250 can be safely brought close to, or placed on top of, the auxiliary structure 1840. As already mentioned in the context of the Fig. As discussed in section 7, in the next step connecting material 730 can be deposited onto the auxiliary structure 1840 and / or the sacrificial tip 450, 1250 (in the Fig. 19 not shown). Then, by a relative movement between the photomask 500 and the sacrificial tip 450, 1250, the particle 550 is lifted out of the gap of the mask 500 (in the Fig. 19 not shown).

[0137] As part of the Fig. 20, Fig. 21 to Fig. 22 A modification of the second embodiment is described below for the case where a small particle 550 is present between periodic linear pattern elements 520 (lines and spaces) on the substrate 510 of the photolithographic mask 500. The initial configuration is shown in diagram 2000 of the Fig. Figure 20 illustrates that neither the sacrificial tip 450, 1250 of the manipulator 300 nor the opening 1420 of the cantilever 1410 of the manipulator 300 can be positioned near the particle 550 without risk.

[0138] Similar to the context of Fig. In process 18, an auxiliary structure 2040 is deposited onto the particle 550 using a particle beam-induced deposition process. The precursor gases 1820 described above can be used as precursors. Diagram 2050 of the Fig. Figure 20 shows the auxiliary structure 2040 deposited on particle 550. At this point, the further particle removal process branches. In a first branch, it is possible to proceed similarly to the Fig. Section 19 explains how to position the opening 1420 of the cantilever 1410 of the manipulator 1400 above the auxiliary structure 2940. The further process sequence is then described in the discussion of the Fig. 16 and Fig. 17 described.

[0139] A second branch will be developed below based on the Fig. 21 and Fig. 22 explained. As shown in diagram 2100 of the Fig. As illustrated in Figure 21, in the next step the auxiliary structure 2040 deposited on particle 550 is thinned using an EBIE (Electron Beam Induced Etching) process. For example, steam can be used as the etching gas if carbon is the main component of the auxiliary structure 2040. Other possible etching gases are described above. If necessary, an additional gas in the form of an oxidizing agent can be added to the etching gas. In the Fig. In the example shown in Figure 21, the modified auxiliary structure 2140 has a cylindrical shape after completion of the etching process. The EBIE process is continued until the diameter of the modified auxiliary structure 2140 is smaller than the diameter of the opening 1420 of the cantilever 1410 of the manipulator 1400.

[0140] In the next step, as shown in diagram 2150, the Fig. Figure 21 illustrates how the opening 1420 of the cantilever 1410 is positioned above the modified auxiliary structure 2140, and then the modified auxiliary structure 2140 is inserted into the opening 1420 of the cantilever 1410. Subsequently, by depositing bonding material between the edges of the opening 1420 and the modified auxiliary structure 2140, the particle 550 is connected to the manipulator 1400. The depositing of bonding material is described above in relation to the Fig. 7, Fig. 16 and Fig. 17 described. In the last step, which is shown in diagram 2250 of the Fig. As illustrated in Figure 22, by performing a relative movement between the photomask 500 and the manipulator 1400, the small particle 550 is lifted out of the narrow gap between the two linear pattern elements 520.

[0141] Based on the Fig. 23 and Fig. Section 24 describes a further embodiment for removing a particle from a photolithographic mask 500. Diagram 2305 of the Fig. Figure 23 shows a manipulator 2300. This has a cantilever 2310 and a retaining plate 1430. Unlike the manipulator 1400 of the Fig. 14. The cantilever 2310 of the manipulator 2300 has no opening. Furthermore, the cantilever 2310 has no measuring tip 320 and no sacrificial tip 450, 1250.

[0142] To remove particle 550 from the substrate 510 of the mask 500, the free end of the cantilever 2310 is first positioned over particle 550. Then, compound material is deposited onto particle 550 by performing a particle beam-induced deposition process. As discussed above during the discussion of the Fig. 7, Fig. 16 and Fig. As explained in Figure 17, to carry out a particle beam-induced deposition process from a gas supply system 1630, a precursor gas 1620 is provided near the particle 550. Unlike in the Fig. 7, Fig. 16 and Fig. However, the particle beam 2330 inducing the deposition process is shown in diagram 2305. Fig. 23 is directed onto the rear side 2370 of the cantilever 2310. The energy of the electrons of the electron beam 2330 is higher in the embodiment described here than in the electron beams 710 and 1610, i.e., the kinetic energy of the electron beam is greater than 5 keV. The electrons of the electron beam 2330 striking the cantilever 2310 generate secondary electrons 2340 in the cantilever 2310.

[0143] Diagram 2355 of the Fig. Figure 23 shows, by way of example, the paths 2360 or trajectories 2360 of some secondary electrons 2340 within the cantilever 2310. Some of the secondary electrons 2340 generated in the cantilever 2310 can leave the front face of the cantilever 2310 through the front face 2380, i.e., the side facing the mask 500 or the particle 550. The front face 2380 of the cantilever 2310 is mainly ejected by primary electrons 2340 scattered within the cantilever 2310. These excite the precursor gas 1620 and thereby induce the deposition of compound material 2440 onto the particle 550 and / or the front face 2380 of the cantilever 2310 from the supplied precursor gas 1620.

[0144] Diagram 2400 of the Fig. Figure 24 schematically illustrates the arrangement of the deposited compound material 2440 between the particle 550 and the front face of the cantilever 2310. The deposited compound material 2440 connects the particle 550 to the cantilever 2310. The arrangement of the deposited compound material 2440 reflects the distribution of scattered electrons between the front face 2380 of the cantilever 2310 and the particle 550. As shown in diagram 2450 of the Fig. As illustrated in Figure 24, the particle 550 coupled to the cantilever 2310 can be removed from the substrate 510 of the mask 500.

[0145] Diagram 2505 of the Fig. Figure 25 shows another example of a manipulator. The manipulator 2500 comprises a mounting plate 2530 to which three cantilevers 2510, 2515, and 2520 are attached. The mounting plate 2530 with the three cantilevers 2510, 2515, and 2520 can also be referred to as a one-dimensional (1D) probe arrangement or as part of a 1D probe arrangement. The cantilevers 2510, 2515, and 2520 of the manipulator 2500 can include the cantilever 310 with a measuring tip 320 and a sacrificial tip 450 or 1250, the cantilever 1410 with the opening 1420, or the cantilever 2310 without a measuring tip 320 and sacrificial tip 450 or 1250, or without an opening 1420. For the sake of simplicity, the following figures do not show a measuring tip 320, a sacrificial tip 450, 1250 or an opening 1420 for the cantilevers 2510, 2515 and 2520.

[0146] In diagram 2505 of the Fig. 25 is located on substrate 510 of mask 500, and particle 550 is located under cantilever 2515. Diagram 2545 of the Fig. Figure 25 presents a vertical section through diagram 2505 after the free end of the central cantilever 2515 of the manipulator 2500 was positioned over the particle 550. Additionally, the vertical distance between the particle 550 and the front of the cantilever 2515 was reduced to a few nanometers by moving the retaining plate 2530 of the manipulator 2500. Diagram 2575 of the Fig. Figure 25 shows the configuration of diagram 2545 after the bonding material 2440 has bonded the cantilever 2515 and the particle 550 by performing a particle beam-induced deposition process. Possible deposition processes are related to the above. Fig. 7, Fig. 16 and Fig. 23 described.

[0147] Diagram 2600 of the Fig. Figure 26 shows the lifting of particle 550, which is connected to the cantilever 2515, after performing a relative movement between the manipulator 2500 and the photomask 500.

[0148] Diagram 2650 of the Fig. Figure 26 illustrates the bending of the cantilever 2515 of the manipulator 2500, loaded with particle 550, away from the photomask 500. In the context of the discussion of Fig. Section 3 describes various ways to temporarily bend, activate, or deactivate a cantilever. Furthermore, it discusses measurement methods that make it possible to detect bending or curvature of a cantilever.

[0149] To permanently bend a cantilever, it can be made from a shape memory material, such as a shape memory alloy or a shape memory polymer. It is also possible to induce a phase transition in the cantilever that causes it to bend. A commonly used shape memory alloy is Nitinol, an alloy of nickel and titanium. Permanently bending a cantilever 2510, 2515, or 2520 is disadvantageous because this type of cantilever can only be used to remove a single particle 550.

[0150] Furthermore, it is possible to remove the cantilever 2515 loaded with a particle 550 from the mounting plate 2530 using a particle beam-induced etching process.

[0151] In the based on the Fig. 26 and Fig. In the embodiment described in Figure 27, the cantilevers 2510, 2515, and 2520 are not deflected. Instead, the manipulator 2550 is moved as a whole. Only after a cantilever 2515 has been loaded with a particle 550 is it bent away from the mask so that the mask 500 cannot be damaged when another particle is removed with one of the still unloaded cantilevers 2510 and 2520.

[0152] Diagram 2700 of the Fig. 27 presents the configuration of diagram 2650 of the Fig. 26 after positioning the cantilever 2520 over a second particle 2750 to be removed. The next step of depositing compound material 2440 on the second particle 2750 is shown in diagram 2600. Fig. 26 executed. Finally, diagram 2750 shows the Fig. 27 the configuration of diagram 2700 from a perspective view.

[0153] After loading a cantilever 2510, 2515 and 2520 with a particle 550, 2750, the particles 550, 2750 can be separated from the cantilevers 2510, 2515 and 2520, if necessary after performing a corresponding analysis process to determine the material composition, using a particle beam-induced etching process, for example an EBIE process, and the manipulator 2500 is then available for a further particle removal process.

[0154] The Fig. 28 and Fig. 29 reproduce the sequence of particle removal of the Fig. 26 and Fig. 27 with the difference that in the Fig. 28 and Fig. 29 not the manipulator 2500 and thus not all cantilevers 2510, 2515 and 2520 are lowered onto or near the particle 550, 2750, but only the cantilever 2515 or 2520 receiving the particle 550, 2750. The embodiment of the Fig. 28 and Fig. 29 is advantageous, since only the cantilever 2515 or 2520 to be loaded is brought into the immediate vicinity of the mask 500 or the particle 550, 2750, and the other cantilevers are removed from a possible undesired interaction with the photomask 500.

[0155] The Fig. Figure 30 shows a top view of a manipulator 3000, which is implemented in the form of a two-dimensional (2D) probe arrangement or a 2D probe array. The manipulator 3000 comprises a mounting plate 3030 and in the Fig. The nine cantilevers 3010, 3015, 3020, 3025, 3035, 3040, 3045, 3050 and 3055 are shown in the example 30. The cantilevers 3010 to 3055 of the manipulator 3000 can be cantilevers 310 with a measuring tip 320 and / or a sacrificial tip 450, 1250, or can be cantilevers 1410 with an opening 1420, and / or can include cantilevers 2310 without a measuring tip 320 and sacrificial tip 450, 1250 or without an opening 1420.

[0156] If the 2D probe array of the manipulator 3000 becomes too large, it can be difficult to position the manipulator 3000 according to the individual particles 550, 2750 to be removed without damaging the mask 500 and / or the probe array of the manipulator 3000. This is especially true if the mask 500 has an electrostatic charge.

[0157] The Fig. Figure 31 presents a cross-section of a Manipulator 3100, which at least partially avoids this problem. The Manipulator 3100 of Fig. 31 has a curved holding plate 3130 about a vertical axis. The manipulator 3100 can additionally have a second curvature about a horizontal axis. The radii of curvature of the two curvatures of the holding plate 3130 can be the same or different.

[0158] The Manipulator 3100 features a probe array with 7×7 cantilevers. The one in the Fig. The section shown in Figure 31 passes through cantilevers 3110, 3115, 3120, 3125, 3135, 3140, and 3145. Diagram 3105 shows the approach and positioning of cantilever 3125 of the manipulator 3100 over particle 550. After positioning the cantilever 3125 over particle 550, the particle 550 is connected to the cantilever 3125 by depositing the bonding material 2440 between the particle 550 and the cantilever 3125. For simplicity, the bonding material 2440 is shown in the Fig. 31 suppressed.

[0159] Diagram 3135 of the Fig. Figure 31 shows the cantilever 3125 loaded with particle 550 and the lowering of the manipulator 3100, so that the cantilever 3115 comes to rest above a second particle 2750 of the mask 500. By depositing bonding material 2440 onto the particle 2750 and / or the cantilever 3115 of the manipulator 3100, the particle 2750 is bonded to the cantilever 3115.

[0160] Diagram 3170 illustrates an arrangement in which the manipulator 3100, which has already picked up the particles 550 and 2750, is placed over a third particle 3150, so that the cantilever 3140 can be connected to the particle 3150 - again by performing a particle beam-induced deposition process.

[0161] The Fig. Figure 32 shows a schematic section through some important components of a device 3200 with which a method according to the invention can be carried out. The device 3200 comprises a modified scanning particle microscope 3210 in the form of a scanning electron microscope (SEM) 3210 and a scanning probe microscope 3270 in the form of an atomic force microscope (AFM) 3270. It is also possible that the device 3200 comprises a manipulator device instead of, or in addition to, the scanning probe microscope 3270 (in the Fig. 32 not shown).

[0162] In the SEM 3210 of Fig. 32 An electron gun 3212 generates an electron beam 3215, which is directed by the imaging elements arranged in the column 3217, which are in the Fig. The electron beam 32 (not shown) is directed at position 3220 onto the sample 3222, which may include the mask 500. The sample 3222 is arranged on a sample stage 3225. The imaging elements of the column 3217 of the SEM 3210 can further rasterize or scan the electron beam 3215 across the sample 3222. The sample 3222 can be examined using the electron beam 3215 of the SEM 3210. The electron beam 3215 can also be used to induce a particle beam-induced deposition process and / or an EBIE process. Furthermore, the electron beam 3215 of the SEM 3210 can be used to analyze a particle 550, 2750, or 3150.

[0163] The electrons backscattered from the sample 3222 by the electron beam 3215 and the secondary electrons generated in the sample 3222 by the electron beam 3215 are registered by the detector 3227. The detector 3227, which is arranged in the electron column 3217, is referred to as an "in-lens detector". The detector 3227 can be installed in the column 3217 in various embodiments. The detector 3227 is controlled by the control unit 3230 of the device 3200.

[0164] The device 3200 includes a second detector 3235. The second detector 3235 is designed to detect electromagnetic radiation, particularly in the X-ray range. This allows the detector 3235 to analyze the particles 550, 2750, and 3150, which are excited by the electron beam 3215, in order to determine their material composition. During the analysis of the particles 550, 2750, and 3150, the sample stage 3225 is lowered and / or the sample 3222 is removed from the beam direction of the electron beam 3215. The detector 3235 is also controlled by the control unit 3230.

[0165] Furthermore, the device 3200 can include a third detector (in the Fig. 32 (not shown). The third detector is often in the form of an Everhart-Thornley detector and is typically located outside column 3217. It is usually used for detecting secondary electrons.

[0166] The device 3200 can include an ion source that provides ions with low kinetic energy in the range of particles 550, 2750, 3150 (in the Fig. 32 not shown). The low-kinetic-energy ions can compensate for the charging of a particle 550, 2750, 3150 and / or a manipulator 300, 1300, 1400, 2300, 2500, 3000. Furthermore, the device 3200 can have a grid at the outlet of the column 3217 of the modified SEM 3210 (in the Fig. (32 not shown). By applying an electrical voltage to the grid, an electrostatic charge of a particle 550, 2750, 3150 and / or a manipulator 300, 1300, 1400, 2300, 2500, 3000, 3100 can also be compensated. Furthermore, it is possible to ground the grid. Thus, the two elements outlined in this section, individually or in combination, form a charge compensation system.

[0167] The control unit 3230 and / or the computer system 3240 can adjust the parameters of the electron beam 3215 to induce a deposition process or an EBIE process and to analyze the particles 550, 2750, 3150. Furthermore, the control unit 3230 of the device 3200 receives the measurement data from the detector 3227, the detector 3235, and / or the Everhart-Thornley detector. The control unit 3230 can generate images from the measurement data, which are displayed on a monitor 3237.

[0168] As already explained above, the electron beam 3215 of the modified SEM 3210 can be used to induce an electron beam-induced deposition process and an EBIE process. To carry out these processes, the exemplary scanning electron microscope 3210 features... Fig. 32 three different storage containers 3245, 3250 and 3255.

[0169] The first storage container 3245 stores a first precursor gas 720, 1150, 1620, 1820, for example a metal carbonyl, such as chromium hexacarbonyl (Cr(CO)6) or a carbon-containing precursor gas, such as styrene. With the aid of the precursor gas stored in the first reservoir 3245, a sacrificial tip 450, connecting material 730, 1730, 2440 and / or an auxiliary structure 1840, 2040 can be deposited in a local chemical reaction onto the measuring tip 320, the cantlever 310, 1410, 2310, 2510, 2515, 2520, 3010 to 3055 and 3115 to 3145 and / or the particle 550, 2750, 3150, wherein the electron beam 3215 of the SEM 3210 acts as an energy supplier to split the precursor gas stored in the first reservoir 3245 at the location where material is to be deposited.This means that by the combined provision of an electron beam 3215 and a precursor gas, an EBID (Electron Beam Induced Deposition) process is carried out for the local deposition of a sacrificial tip 450, of bonding material 730, 1730, 2440 and / or an auxiliary structure 1840, 2040. The modified SEM 3210, in combination with the first reservoir 3245, forms a deposition device.

[0170] An electron beam 3215 can be focused to a spot diameter of a few nanometers. This allows an EBID process to enable the local deposition of compound materials 730, 1730, 2440 with a spatial resolution in the low double-digit nanometer range.

[0171] In the Fig. In the device 3200 shown in Figure 32, the second reservoir 3250 stores an etching gas 920, which enables the execution of a local electron beam induced etching process (EBIE). Using an electron beam induced etching process, a particle 550, 2750, 3150 can be removed from a sacrificial tip 450, 1250, a measuring tip 320, 1320 and / or a cantilever 310, 1410, 2310, 2510, 2515, 2520, 3010 to 3055 and 3115 to 3145. An etching gas can, for example, include xenon difluoride (XeF2), chlorine (Cl2), oxygen (O2), ozone (O3), water vapor (H2O), hydrogen peroxide (H2O2), nitrous oxide (N2O), nitrogen monoxide (NO), nitrogen dioxide (NO2), nitrosyl chloride (NOCl), nitric acid (HNO3), ammonia (NH3), or sulfur hexafluoride (SF6). Thus, the modified SEM 3210, in conjunction with the second storage container 3250, forms a separation device.

[0172] The third storage container 3255 can store an additive or additional gas that can be added, as needed, to the etching gas 920 held in the second storage container 3250 or to the precursor gas 720, 1150, 1620, 1820 stored in the first storage container 3245. Alternatively, the third storage container 3255 can store a second precursor gas or a second etching gas.

[0173] Each of the storage containers 3245, 3250 and 3255 has in the one in the Fig. The scanning electron microscope 3210 shown in Figure 32 has its own control valves 3246, 3251, and 3256 to control the amount of the corresponding gas supplied per unit time, i.e., the gas flow rate at the point 3220 where the electron beam 3215 strikes the sample 3222. The control valves 3246, 3251, and 3256 are controlled by the control unit 3230. This allows the partial pressure ratios of the gas(es) supplied at the processing location 3220 for performing an EBID and / or EBIE process to be adjusted over a wide range.

[0174] Furthermore, in the exemplary SEM 3210, the Fig. 32 Each storage container 3245, 3250 and 3255 has its own gas supply system 3247, 3252 and 3257, which terminates with a nozzle 3248, 3253 and 3258 near the point of impact 3220 of the electron beam 3215 on the sample 3222.

[0175] The storage containers 3245, 3250, and 3255 can have their own temperature setting and / or control element, which allows both cooling and heating of the respective storage containers 3245, 3250, and 3255. This enables the storage and, in particular, the supply of the precursor gas and / or the etching gas(es) 920 at the respective optimal temperature (in the Fig. (32 not shown). The control unit 3230 can control the temperature setting elements and the temperature control elements of the storage containers 3245, 3250, 3255. During the E-BID and EBIE processing operations, the temperature setting elements of the storage containers 3245, 3250 and 3255 can also be used to adjust the vapor pressure of the precursor gases 720, 1150, 1620, 1820 stored therein by selecting an appropriate temperature.

[0176] The device 3200 can comprise more than one storage container 3245 for storing two or more precursor gases 720, 1550, 1620, 1820. Furthermore, the device 3200 can comprise more than one storage container 3250 for storing two or more etching gases 920.

[0177] The one in Fig. The scanning electron microscope 3210 shown in Figure 32 is operated in a vacuum chamber 3260. To perform the EBID and EBIE processes, a negative pressure relative to ambient pressure is necessary in the vacuum chamber 3260. For this purpose, the SEM 3210 features a Fig. 32 a pump system 3262 for generating and maintaining a required vacuum in the vacuum chamber 3260. With the control valves 3246, 3251 and 3256 closed, a residual gas pressure < 10 -4Pa is reached. The pumping system 3262 can include separate pumping systems for the upper part of the vacuum chamber 3260 for supplying the electron beam 3215 of the SEM 3210 and the lower part 3265 or the reaction chamber 3265 (in the Fig. 32 not shown).

[0178] Additionally, the information in the Fig. Figure 32 illustrates an exemplary device 3200 comprising a scanning probe microscope 3270, which is implemented in the device 3200 as an atomic force microscope 3270 or an atomic force microscope (AFM) 3270. The scanning probe microscope 3270 can accommodate the manipulators 300, 1400, 2300, 2500, 3000, and 3100. Furthermore, it is possible to use the AFM 3270 for examining the photomask 500 and / or for analyzing the particle 550, 2750, or 3150.

[0179] The scanning probe microscope 3270 is installed in the device 3200. Fig. Figure 32 shows the measuring head 3275. The measuring head 3275 includes a holding device 3280. The measuring head 3275 is attached to the frame of the device 3200 by means of the holding device 3280 (in the Fig. 32 not shown). A piezo actuator 3282 is attached to the holding device 3280 of the measuring head 3275, which enables movement of the free end of the piezo actuator 3282 in three spatial directions (in the Fig. 32 (not shown). A manipulator 300, 1300, 1400, 2300, 2500, 300 is attached to the free end of the piezo actuator 3282. An example of a cantilever 300 is shown in the Fig. 32. The free end of the cantilever of the manipulator 300, 1300, 1400, 2300, 2500, 3000 has a measuring tip 320, 1320, a sacrificial tip 450, 1250, a measuring tip 320, 1320 and a sacrificial tip 450, 1250, an opening 1420 or none of these elements.

[0180] The measuring head 3275 of the AFM 3270 is rotatably mounted about its holding device 3280, so that the measuring tip 3290 of the AFM 3270 can be rotated about an axis that is parallel to the surface of the sample 3222 or the photomask 500 (in the Fig. 32 not shown).

[0181] In addition to or as an alternative to the scanning probe microscope 3270, the device 3200 can comprise a manipulator device with a manipulator head for receiving the manipulators 300, 1400, 2300, 2500, 3000, 3100 (in the Fig. 32 not shown). The manipulator device can be controlled by the control unit 3230.

[0182] As in the Fig. As symbolized by arrows, the sample stage 3225 can be moved in three spatial directions relative to the measuring head 3275 of the AFM 3270 and / or the point of impact 3220 of an electron beam 3215 by a positioning system 3297. In the example of the Fig. The positioning system 3297 is implemented in the form of several micromanipulators or displacement elements. The movement of the sample stage 3225 in the sample plane, i.e., in the xy-plane perpendicular to the beam direction of the electron beam 3215, can be controlled by two interferometers (in the Fig. 32 not shown). In an alternative embodiment, the positioning system 3297 can additionally include piezo actuators (in the Fig. (Figure 32 not shown). The positioning system 3297 is controlled by signals from the control unit 3230. In an alternative embodiment, the control unit 3230 does not move the sample stage 3225, but rather the holding device 3280 of the measuring head 3275 of the AFM 3270. It is also possible that the control unit 3230 performs a coarse positioning of the sample 3222 or the mask 500 in height (z-direction) and the piezo actuator 3282 of the measuring head 3280 performs a precise height adjustment of the AFM 3270. The control unit 3230 can be part of a computer system 3240 of the device 3200.

[0183] The AFM 3270 can be used to position the manipulator 300, 1300, 1400, 2300, 2500, 3000, 3100 relative to a particle 550, 2750, 3150. Furthermore, the AFM 3270 can be used to remove a manipulator 300, 1300, 1400, 2300, 2500, 3000 loaded with a particle 550, 2750, 3150 from the photolithographic mask 500 by moving it.

[0184] The flowchart 3300 of the Fig. Figure 33 schematically presents the process of removing a particle 550, 2750, 3150 from a photolithographic mask 500. The process begins at step 3310. At step 3320, a manipulator 300, 1300, 2500, 3000, 3100, movable relative to the mask 500, is positioned near the particle 550, 2750, 3150 to be removed. In the next step 3330, the manipulator 300, 1400, 2300, 2500, 3000, 3100 is connected to the particle 550, 2750, 3150 by depositing bonding material 730, 1730, 2440 onto the manipulator 300, 1400, 2300, 2500, 3000, 3100 and / or onto the particle 550, 2750, 3150 from the gas phase. Then, in step 3340, the particle 550, 2750, 3150 is removed by moving the manipulator 300, 1400, 2300, 2500, 3000 relative to the photolithographic mask 500.Then, in step 3350, the removed particle 550, 2750, 3150 is removed from the manipulator 300, 1300, 2500, 3000, 3100 by performing a particle beam-induced etching process, wherein the at least one particle beam-induced etching process removes at least a portion of the manipulator 300, 1300, 250, 3000, 3100. Finally, the process ends in step 3360.

[0185] Finally, the flowchart shows 3400 of the Fig.Figure 34 schematically illustrates the process of removing a particle 550, 2750, 3150 from a photolithographic mask 500. The process begins at step 3410. At step 3420, a manipulator 1400, 2300, 2500, 3000, 3100, movable relative to the mask 500, is positioned near the particle 550, 2750, 3150 to be removed. In the next step 3430, the manipulator 1400, 2300, 2500, 3000, 3100 is connected to the particle 550, 2750, 3150 by depositing compound material 730, 1730, 2440 on the manipulator 1400, 2300, 2500, 3000, 3100 and / or on the particle 550, 2750, 3150 from the gas phase, wherein a particle beam 1610, 2330 inducing the deposition is provided through the manipulator 1400, 2300, 2500, 3000, 3100. Then, in step 3440, the particle 550, 2750, 3150 is removed by moving the manipulator 1400, 2300, 2500, 3000, 3100 relative to the photolithographic mask 500. Finally, the process ends in step 3450.

Claims

[1] Method (3300) for removing a particle (550, 2750, 3150) from a photolithographic mask (500) comprising the following steps: a. Positioning (3320) a manipulator (300, 1300, 2500, 3000, 3100) movable relative to the mask (500) in the vicinity of the particle (550, 2750, 3150) to be removed; b. Connecting (3330) the manipulator (300, 1300, 2500, 3000, 3100) with the particle (550, 2750, 3150) by depositing a bonding material (730, 1730, 2440) on the manipulator (300, 1300, 2500, 3000, 3100) and / or the particle (550, 2750, 3150) from the gas phase; c. Removal (3340) of the particle (550, 2750, 3150) by moving the manipulator (300, 1300, 2500, 3000, 3100) relative to the photolithographic mask (500); and d. Separating the removed particle (550, 2750, 3150) from the manipulator (300, 1300, 2500, 3000, 3100) by performing a particle beam-induced etching process that removes at least a portion of the manipulator (300, 1300, 2500, 3000, 3100). [2] Method according to the preceding claim, further comprising the step: Detachment of a sacrificial tip (450, 1250) on the manipulator (300, 1300, 2500, 3000, 3100). [3] Method according to the preceding claim, wherein the deposition of the sacrificial tip (450, 1250) comprises the application of at least one of the following steps: a particle beam-induced deposition process and an electric field-induced deposition process. [4] Method according to claim 2 or 3, wherein the manipulator (300, 1300, 2500, 3000) has a measuring tip (310) for examining the photolithographic mask (500) and the method further comprises the following step: depositing the sacrificial tip (450, 1250) on the measuring tip (310). [5] Method (3400) for removing a particle (550, 2750, 3150) from a photolithographic mask (500) by the following steps: a. Positioning (3420) a manipulator (1400, 2300, 2500, 3000, 3100) movable relative to the mask (500) in the vicinity of the particle (550, 2750, 3150) to be removed; b. Connecting (3430) the manipulator (1400, 2300, 2500, 3000, 3100) to the particle (550, 2750, 3150) by depositing a bonding material onto the manipulator (1400, 2300, 2500, 3000, 3100) and / or the particle (550, 2750, 3150) from the gas phase, wherein a particle beam (1610, 2330) inducing the deposition is provided through the manipulator (1400, 2300, 2500, 3000, 3100); and c. Removal (3440) of the particle (550, 2750, 3150) by moving the manipulator (1400, 2300, 2500, 3000, 3100) relative to the photolithographic mask (500). [6] Method according to the preceding claim, wherein the manipulator (1400, 2500, 3000, 3100) has an opening (1420) and / or wherein the particle beam (1610) inducing deposition is provided through the opening (1420) of the manipulator (1400, 2500, 3000, 3100). [7] Method according to the preceding claim, wherein the compound material (730, 1730, 2440) is deposited on at least one edge of the opening (1420) of the manipulator (1400, 2500, 3000, 3100). [8] Method according to any of the preceding claims, wherein step b. comprises: providing a precursor gas (720, 1620) in the region of the particle (550, 2750, 3150) and the manipulator (300, 1300, 1400, 2300, 2500, 3000, 3100). [9] Method according to the preceding claim, wherein step b. comprises: providing a means (710, 1610) in the region of the particle (550, 2750, 3150) and the manipulator (300, 1300, 1400, 2300, 2500, 3000, 3100) for modifying the precursor gas (720, 1190, 1620) so that the compound material (730, 1730, 2440) is deposited. [10] Method according to the preceding claim, wherein the means (710, 1610) comprises at least one of the following elements: a focused particle beam (710, 1610) and an electric field (1190) between the particle (550, 2750, 3150) and the manipulator (300, 1300, 1400, 2300, 2500, 3000, 3100). [11] Method according to any of the preceding claims, further comprising the step of: analyzing a material of the removed particle (550, 2750, 3150). [12] Method according to any of the preceding claims, further comprising the step of depositing an auxiliary structure (1840, 2040) onto the particle (550, 2750, 3150). [13] Method according to any of the preceding claims further comprising the step of: compensating for an electrostatic charge during the deposition of the compound material (730, 1730, 2440) with a charge compensation system. [14] Device (3200) for removing a particle (550, 2750, 3150) from a photolithographic mask (500) comprising: a. a manipulator (300, 1300, 1400, 2300, 2500, 3000, 3100) movable relative to the mask (500) and movable in the vicinity of the particle (550, 2750, 3150) to be removed, wherein the device (3200) is configured to tilt the manipulator (300, 1300, 2500, 3000, 3100) against a normal direction of the photolithographic mask (500); b. a separation device configured to separate a compound material (730, 1730, 2440) onto the manipulator (300, 1300, 1400, 2300, 2500, 3000, 3100) and / or the particle (550, 2750, 3150) from the gas phase in order to connect the manipulator (300, 1300, 1400, 2300, 2500, 3000, 3100) to the particle (550, 2750, 3150); and c. a separation device designed to separate the removed particle (550, 2750, 3150) from the manipulator (300, 1300, 2500, 3000, 3100) by performing a particle beam-induced etching process that removes at least a partial area of ​​the manipulator (300, 1300, 2500, 3000, 3100). [15] Device according to the preceding claim, wherein the separation device is further configured to deposit a sacrificial tip (450) on the manipulator (300, 1300, 2500, 3000, 3100). [16] Device (3200) for removing a particle (550, 2750, 3150) from a photolithographic mask (500); a. a manipulator (1400, 2300, 2500, 3000, 3100) movable relative to the mask (500), which is movable in the vicinity of the particle (550, 2750, 3150) to be removed, and b. a separation device configured to separate a compound material (730, 1730, 2440) onto the manipulator (1400, 2300, 2500, 3000, 3100) and / or the particle (550, 2750, 3150) from the gas phase in order to connect the manipulator (1400, 2300, 2500, 3000, 3100) to the particle (550, 2750, 3150), wherein the separation device is further configured to provide a particle beam (1610, 2330) inducing the separation through the manipulator (1400, 2300, 2500, 3000, 3100). [17] Device according to the preceding claim, wherein the device (3200) comprises a separating device configured to separate the removed particle (550, 2750, 3150) from the manipulator (1400, 2300, 2500, 3000, 3100). [18] Device according to one of claims 14-17, wherein the device (3200) comprises a detector (3265) for detecting X-ray radiation. [19] Computer program comprising instructions which, when executed by a computer system, cause the device (3200) according to one of claims 14, 15 or 18 to perform the process steps according to one of claims 1 to 4 or 8-13. [20] Computer program comprising instructions which, when executed by a computer system, cause the device (3200) according to any one of claims 16 to 18 to perform the method steps according to any one of claims 5 to 13.

Images