Method and device for mask repair

Abstract

Method (200) for processing an object (402) for lithography comprising: a first gas (G1) comprising first molecules; providing (210) a particle beam (409) on the object for removing a first material (A) of the object based at least partially on the first gas; wherein the first material comprises iridium; wherein the first material further comprises at least a second element; wherein the second element comprises tantalum.

Description

1. Technical area

[0001] The present invention relates to a method, a device and a computer program for processing a object for lithography. In particular, the present invention relates to a method for removing a material, a corresponding device and a method for lithographic processing of a wafer, and a Computer program for carrying out the procedures. 2. State of the art

[0002] In the semiconductor industry, increasingly smaller structures are being produced on a wafer in order to increase the To ensure integration density, lithographic processes are used to manufacture the structures. which image them on the wafer. The lithographic processes can be, for example, photolithography, ultraviolet (UV) Lithography, DUV lithography (i.e. lithography in the deep ultraviolet spectral range), EUV Lithography (i.e. lithography in the extreme ultraviolet spectral range), X-ray lithography, Nano imprint lithography, etc. Masks are usually used as objects for lithography (e.g. Photomasks, exposure masks, reticles, stamps in nanoimprint lithography, etc.), which comprise a pattern to to image the desired structures, e.g. on a wafer.

[0003] In a lithographic process, a mask can be subjected to high physical and chemical be exposed to stress (e.g. during mask exposure, mask cleaning, etc.). Accordingly High demands are placed on the durability of the mask materials. Over time, certain mask materials for certain mask structures (such as tantalum or chromium for radiation-absorbing and / or phase-shifting mask structures). For example, the mask materials be designed so that a small layer thickness of an absorber of the mask and / or a specific phase-shifting property of a mask structure. With the advancement of technical development in lithography, However, the high requirements for mask materials will be further tightened. In order to continue to produce resistant To ensure mask materials that have the desired radiation-absorbing and / or phase-shifting properties In the field of lithography, alternative mask materials and the production of these constructed masks were examined.

[0004] Since mask defects cannot generally be excluded in complex mask production, However, mask materials can also form as (local) mask defects on the mask (e.g. as defects, excess material, malformed material, overlying particles, etc.).

[0005] However, previous methods for processing masks are based exclusively on technically long-established Mask materials designed.

[0006] The present invention is therefore based on the object of simplifying the processing of objects for lithography optimize. 3. Summary of the invention

[0007] This object is at least partially achieved by the various aspects of the present invention.

[0008] A first aspect of the invention relates to a method for processing an object for lithography.

[0009] The method comprises providing a first gas comprising first molecules. Furthermore, the Method providing a particle beam on the object for removing a first material of the object based at least in part on the first gas, wherein the first material comprises iridium.

[0010] The invention addresses, among other things, the problem of removing materials on an object for lithography which are designed to be resistant to removal under chemical and / or physical stress.

[0011] It has recently been discussed whether parts of an object for lithography made of an iridium-containing material to be produced to meet current and future requirements in lithography.

[0012] Due to the iridium-containing material, structures of the object constructed from it can, for example, exhibit increased chemical Resistance to the requirements of lithography. A structure of the object can, for example, be in length, Width and / or height three-dimensional geometry, a topology level, an elevation, a depression of the object or any topological deviation with respect to a planar plane of the object. Furthermore, by means of iridium-containing material the desired optical properties of the structures can be ensured (e.g. desired radiation-absorbing and / or phase-shifting properties of the structures).

[0013] The iridium-containing material does not necessarily have to be present in a structure of the object, but can also be present in a be incorporated into any layer of the object to meet the requirements of lithography. For example, The iridium-containing material can also be present in a (largely) planar layer of the object. It is conceivable that the iridium-containing material is incorporated into specific functional layers of the object (e.g. in a Cover layer and / or as material of a reflective layer of the object, e.g. as material of a Bragg mirror). For example, iridium-containing material does not have to be limited to optical functions, but can also have other functions fulfill (e.g. a mechanical and / or chemical function, such as a protective function).

[0014] The iridium-containing material can, for example, be specifically designed to facilitate the removal of the first material during chemical / physical influences. The iridium-containing material can, for example, be designed to withstand Abrasion / wear of mask structures constructed from them, even with permanent or regular chemical / physical stress. The iridium-containing material can, for example, be adapted to the extreme conditions lithographic processes in which the object is to be used for lithography. For example, The object may be exposed to a (damaging) plasma during a lithographic process. For example, it may be used for a lithographic process may be necessary to expose the object to a hydrogen environment (e.g. to avoid Defects). During lithographic exposure of the object, a (parasitic) highly reactive hydrogen plasma with hydrogen radicals, which can affect the material of the object. The plasma represents represents a high chemical / physical stress on the object and can result in material removal as well as cause material damage to the object (e.g. in a similar way to plasma etching). However, the material-removing effect is not desired for the object of lithography, as this would affect the properties of the object and thus the quality of the lithographic process. Therefore, the iridium-containing Material (explicitly) designed to ensure high resistance of the first material to the material-removing effect of a plasma (e.g. especially the highly reactive hydrogen plasma). Furthermore, the The object may be exposed to numerous other mechanical / chemical influences during lithography, which (e.g. in combination with the plasma effect) can damage the object. For example, the other damaging Influences strong temperature fluctuations, exposure radiation, as well as chemical reactions of the object with Purge gases or subsequent cleaning processes. The iridium-containing material can therefore usually be designed to fundamentally protect the entirety of the damaging material-removing influences in lithography so that mechanical / chemical wear and removal of the iridium-containing material is difficult.

[0015] The inventors have recognized that such an iridium-containing material can be removed by particle beam induced removal. This approach can, for example, enable the processing of excess iridium-containing material (e.g. defective iridium-containing material). The inventive concept is therefore based on materials that have just are designed to be resistant to removal, using a particle beam-based process.

[0016] The inventors have come to the unexpected realization that iridium-containing material of a lithographic object can be removed with the help of a provided gas and a provided particle beam (e.g. via a particle beam induced etching). This was a surprising discovery for the inventors, as it was not foreseeable that the first material resistant to the aggressive conditions of lithography is particle beam-based processed or even removed (e.g. without using a plasma). This finding was of great importance to the inventors This is made even more difficult because, according to the prevailing opinion, iridium can only be extracted wet-chemically using highly heated (boiling) Aqua regia is to be etched.

[0017] It was also unexpected for the inventors, considering the resistant (iridium-containing) first material, that a particle beam-based removal of the first material, providing a gas which first molecules According to the invention, it is not necessary to use a complex gas mixture (e.g. with different types of molecules that are designed for the resistant material). This allows ensure that the complexity of particle beam-based removal is reduced, which, for example, allows easier process control of the method according to the invention can be achieved (since, for example, the provision of a single gas places lower demands on the technical implementation than the provision of a gas mixture of, for example, two or several different gases). The invention therefore makes it possible to process objects for lithography that Materials made of a (resistant) iridium-containing material. The first material can, for example, be designed so that there are at least 20, at least 50, at least 100 or even at least 1000 cleaning cycles, which are carried out at a (UV, e.g. EUV or DUV) mask cleaning is carried out, essentially unchanged (so that, for example, in the case of a mask that the first material as part of a pattern element of the mask, the cleaning cycles do not produce any printable errors are generated).

[0018] The object for lithography as described herein may, for example, comprise a lithographic mask. lithographic mask can be designed, for example, to be used in lithography for the production of semiconductor-based chips (e.g., when exposing a semiconductor-based wafer). The lithographic mask can further include any type of lithographic mask that creates an image based on a source of electromagnetic radiation (of any wavelength) and a pattern included on the lithographic mask The image can include a transformation of the pattern. The lithographic mask can, for example, be an EUV mask, a DUV mask, a UV mask, an X-ray lithography mask, a binary mask, a radiation-absorbing and / or phase-shifting mask etc. The object for lithography can be, for example, an object for optical Lithography (ie a lithographic process based on exposure radiation). Furthermore, the lithographic mask may also include a stamp for nanoimprint lithography. Furthermore, the object may include a mask for the Lithography, which can image a pattern based on a source of particles.

[0019] In one example, the object for lithography may also include a mask blank. Mask blanks are described in lithographic industry is a well-known starting material for a mask. The mask blank cannot, for example, Structures, like the mask itself, include its layer material.

[0020] In one example of the method, the first gas may be provided locally on the object. For example, The first gas is supplied locally above the object via a gas pipeline. Local supply can be used, for example, include that a concentration gradient of the first gas exists over the object. For example, the local Provision is made possible that the first gas is present in a locally limited area of ​​the object or that there is a particle beam-induced reaction. Therefore, the entire object must (not necessarily) be exposed to the first gas be exposed.

[0021] In one example, the first gas (and / or particle beam) may be (e.g., substantially only) in a The workspace of the object can be provided. This workspace can, for example, be a local area of ​​the object for the Lithography. For example, the first gas may (e.g., essentially only) be within a region of 5 mm × 5 mm or 3 mm x 3 mm. However, it is also conceivable that the work area covers the entire object for lithography. The work area can also have any surface dimension, shape and / or (three-dimensional) geometry. For example, the working area can be of a size that corresponds to a certain dimension of the object. For example, the specific dimension can be a critical dimension CD of a Pattern element (e.g. pattern elements) of the object.

[0022] The pattern element can, for example, be part of a mask structure, part of the layers of a mask structure, and / or the mask structure itself. A pattern element can, for example, include a structure of the object that is A defined spatial design in lithography achieves a desired effect. For example, the Pattern element can be designed to create a pattern in lithography. For example, the pattern element can also be designed to adjust an optical effect (e.g. contrast adjustment).

[0023] The critical dimension CD can, for example, be a defined structural width of the pattern element as well as a defined distance between two (characteristic) pattern elements. The working area can, for example, be a Area A, which results from the critical dimension CD of the pattern element (e.g. A can be a function of the critical dimension CD, with A = f(CD), e.g. A can be proportional to the critical dimension). Furthermore, The removal of the first material within the work area must be carried out in such a way that the first material is not is not necessarily removed from the entire area of ​​the work area, but (locally) in a part of the workspace. Alternatively, the removal can be done within the workspace in such a way that the first material is removed over the entire surface of the work area. Furthermore, the provision of the first gas targeted on a part of the work area (e.g. via a locally positionable gas line with a Gas nozzle). The particle beam can also be provided in such a way that it is directed onto a part of the working area so that the particles of the particle beam radiate onto the partial area. Furthermore, the Methods include that the particle beam is controlled locally in the sub-area or within the working area and / or focused (e.g. to locally control a particle beam-induced etching reaction).

[0024] In one example, the method of the first aspect comprises completely For example, the process can make it possible that the first material after removal is no longer in the The first material can therefore be removed without leaving any residue using the process.

[0025] In one example, the first material comprises a layer material of the object. Thus, the first material can be any part of the object.

[0026] As described herein, the first material may be, for example, a layer material of a (spatially defined) structure of the The first material can, for example, also include a layer material of any layer of the object. For example, the layer material may comprise part of a top layer of the object. For example, One or more structures may be adjacent to the top layer. For example, the layer material may also be part of a reflective layer stack of the object.

[0027] In one example, the first material comprises a layer material of a pattern element of the object. The first Material can, for example, include a part of a pattern element of the object. The first material can, for example, also include a part a defective pattern element of the object.

[0028] In one example, the first material comprises a radiation-absorbing and / or a phase-shifting Layer material of the object. For example, the radiation-absorbing and / or phase-shifting layer material Be part of a pattern element of the object.

[0029] In one example, the radiation-absorbing (and / or phase-shifting) layer material may be capable of to absorb radiation associated with the object. For example, this radiation associated with the object comprise electromagnetic radiation with a specific wavelength which, in a lithographic process, for which the object is designed. For example, the radiation associated with the object an exposure radiation of the object in the lithographic process. The specific wavelength of the Exposure radiation can be understood as the lithographic wavelength of the object.

[0030] In one example, the method comprises the layer material being a material of an absorption layer of the The absorption layer can comprise the layer of the pattern element that is explicitly which is oriented to absorb radiation of lithographic wavelength. The (iridium-containing) first material can, for example, be designed to allow a low layer thickness of the absorption layer.

[0031] In one example, the object for lithography comprises an EUV mask for an EUV lithography process, wherein the lithographic wavelength (ie the wavelength of the exposure radiation) in this case can be 13.5 nm. Furthermore The radiation can be used, for example, for a DUV lithography process (with e.g. 193 nm or 248 nm lithographic wavelength), an i-line lithography process (with e.g. 365 nm lithographic wavelength), as well as any other Lithography processes (e.g. with a different lithographic wavelength) depending on the object.

[0032] In one example, the first material has an intrinsic material parameter that indicates a significant (e.g. high) absorption of the lithographic wavelength of the object (e.g. an absorption coefficient, a Absorption contribution, an imaginary part of the refractive index of the first material).

[0033] It is also conceivable that the significant absorption is defined by a (low) reflectivity of the first material For example, the reflectivity of the first material (e.g. in the range of the lithographic wavelength) can be a maximum of 25 percent, preferably a maximum of 20%, more preferably a maximum of 17%. Furthermore, the first material may be a material which is typically present in the object to absorb the lithographic wavelength (e.g. a Material that corresponds to an absorption layer (e.g. a pattern element) of the object).

[0034] In a further example, the first material not only has an intrinsic material parameter per se, which indicates significant absorption. In addition, the first material can be geometrically designed in such a way that it can effectively absorb the radiation associated with the object in a local area of ​​the object. For example, the first material in a (local) area of ​​the object can be geometrically constructed in such a way that it extends beyond its absorbing material property and its geometric structure a significant absorption of the radiation of the lithographic wavelength in the (local) area. In this case, the first material in the (local) Area can make an imaging contribution to a lithographic process, since an actual (ie effective) Absorption of radiation of lithographic wavelength is present. The geometry of the first material can be determined, for example, by the Layer thickness of the material, or over a distance that a radiation of lithographic wavelength at a lithographic process through the first material (ie an absorption distance). Absorption distance can be, for example, the optical refraction of the radiation of lithographic wavelength or a beam vector the exposure radiation. For example, the method may comprise applying a very thin layer of an inherently (i.e. i.e. intrinsically) absorbing material is not removed, since this thin layer absorbs the radiation of lithographic wavelength cannot absorb geometrically significantly and thus cannot provide any actual (ie effective) imaging contribution to a corresponding lithographic process. For example, the significant absorption over the Layer thickness or absorption distance of the first material must be defined or calculated: The layer thickness of the first material may be at least 20 nm, preferably at least 35 nm, more preferably at least 50 nm, most preferably at least 60 nm. However, the layer thickness of the first material can also be less than 60 nm, e.g. less than 50 nm or less than 35 nm. The significant absorption can be further described, for example, as the intensity of the radiation of lithographic wavelength by 70%, preferably 80%, most preferably 90% at a lithographic process (across the first material).

[0035] In one example, the extinction coefficient β of the first material (e.g. in the lithographic wavelength) comprise a value of at least 0.038, at least 0.04, at least 0.041, or at least 0.042.

[0036] In one example, the extinction coefficient β of the first material (e.g. in the lithographic wavelength) may have a value of maximum 0.05, maximum 0.049, maximum 0.048 or maximum 0.047.

[0037] In one example, the extinction coefficient β of the first material (e.g. in the lithographic wavelength) a value between 0.038 and 0.05, between 0.04 and 0.049, between 0.041 and 0.048 or between 0.042 and 0.047.

[0038] In one example, the phase-shifting (and / or radiation-absorbing) layer material may be capable of shift the phase of the radiation associated with the object. For example, the (iridium-containing) first Material can also be designed to provide a phase-shifting property of a pattern element of the object for lithography In one example, the object may include a phase-shifting mask for EUV lithography.

[0039] In one example, the dispersion coefficient δ of the first material (e.g. in the lithographic wavelength) comprise a value of at least 0.08, at least 0.09, at least 0.091, or at least 0.092.

[0040] In one example, the dispersion coefficient δ of the first material (e.g. in the lithographic Wavelength) can have a value of maximum 0.12, maximum 0.11, maximum 0.1 or maximum 0.099.

[0041] In one example, the dispersion coefficient δ of the first material (e.g. in the lithographic wavelength) a value between 0.08 and 0.12, between 0.09 and 0.11, between 0.091 and 0.1 or between 0.091 and 0.099.

[0042] In one example, the first gas may be considered as a substantial etching gas for removing the first material The first gas can, for example, be designed in such a way that it has a substantial influence on the etching behavior of the first material. For example, the molecules of the first gas can be selected in such a way that they have a corrosive / removing effect of the first material. The first molecules can also be selected in such a way that they, in conjunction with a reaction induced by the particle beam, a corrosive / removal effect of the first material cause.

[0043] In one example, the first molecules may comprise a halogen atom. The inventors have recognized that For removing the (iridium-containing) first material, a gas is particularly suitable which comprises molecules which Such a first gas (a substantial etching gas) may be used in conjunction with the provided Particle beam can advantageously remove the resistant first material in a technically desired manner. For example, With such a first gas, removal residues, long etching times, inhomogeneous material removal during the procedure of the first aspect can be avoided.

[0044] In one example, the halogen atom may comprise at least one of the following: fluorine, chlorine, bromine, iodine. For example, the first molecules may contain fluorine. For example, the first molecules may also contain chlorine. The first material can therefore be removed using a chlorine chemistry and / or a fluorine chemistry in a particle beam-induced manner.

[0045] In one example, the first molecules may comprise a halogen compound. For example, the Halogen compound comprises a chemical compound having at least one halogen atom, wherein the Halogen atom a chemical compound with at least one other chemical component (e.g. another any chemical element or atom and / or a white chemical group / compound, etc.). In one example, the halogen compound can only Halogens of the same type (e.g. the first molecules can include F, Cl, Br, etc.). 2 2 2

[0046] In one example, the first molecules may comprise a noble gas halide. For example, the noble gas halide may comprise a chemical compound having at least one halogen atom and at least one noble gas atom.

[0047] In one example, the noble gas halide comprises at least one of the following: xenon difluoride, XeF , 2 Xenon dichloride, XeCl , xenon tetrafluoride, XeF , xenon hexafluoride, XeF . The inventors have recognized that 2 4 6 such noble gas halides (e.g. in particular xenon difluoride) in the process of the first aspect, the resistant first material can be advantageously removed in a technically desired manner.

[0048] In another example, the first molecules comprise a quadrupole moment (or a multipole moment with at least four poles), which is greater than zero. For example, xenon difluoride can have a quadrupole moment greater than zero.

[0049] In one example, the first molecules comprise polar molecules. It has been found that polar molecules with a dipole moment can be suitable for the method. In another example, the first molecules but also non-polar molecules. The invention is further based on the concept that non-polar Molecules without a dipole moment can be suitable for the process. In an additional example The first molecules comprise triatomic molecules. According to the invention, complex Compounds with more than three atoms per molecule for a suitable process of the first aspect.

[0050] In one example, the first material may further comprise at least one second element. The second element may be understood as part of any substance comprised in the first material (ie the second element can be, for example, part of a substance compound, a chemical element, etc.). The first material does not necessarily have to be be composed exclusively of iridium. The first material can also be (stoichiometrically) in the form Ir Z away be described with a > 0, b ≥ 0, where Z represents at least the second element (or one or more further chemical elements).

[0051] In one example, the iridium content of the first material may comprise at least 0.1 atomic percent (at.%).

[0052] For example, the iridium content of the first material may be at least 1 atomic percent, at least 5 atomic percent, at least 10 atomic percent, at least 20 atomic percent, at least 30 atomic percent, at least 40 atomic percent or at least 45 atomic percent.

[0053] In one example, the iridium content of the first material may be at least 50 atomic percent, at least 70 atomic percent, at least 80 atomic percent or at least 90 atomic percent.

[0054] In one example, the iridium content of the first material may be 100 atomic percent or a maximum of 99.9 atomic percent include.

[0055] For example, the iridium content of the first material may be a maximum of 90 atomic percent, a maximum of 80 atomic percent, maximum 70 atomic percent, maximum 60 atomic percent, maximum 50 atomic percent or maximum 40 atomic percent.

[0056] In one example, the iridium content of the first material may be a maximum of 30 atomic percent, a maximum of 20 atomic percent, maximum 10 atomic percent, maximum 5 atomic percent or maximum 2 atomic percent.

[0057] In one example, the iridium content of the first material may comprise a value between 0.1 at.% and 99.9 at. %.

[0058] In one example, the iridium content of the first material may comprise a value between 1 at.% and 99.9 at.%. between 5 at.% and 99.9 at.%, between 10 at.% and 99.9 at.%, between 20 at.% and 99.9 at.%, between 30 at.% and 99.9 at. %, between 40 at. % and 99.9 at. %, between 50 at. % and 99.9 at. % or between 60 at. % and 99.9 at. %.

[0059] In one example, the iridium content of the first material may comprise a value between 0.1 at.% and 90 at.%. between 0.1 at. % and 80 at. %, between 0.1 at. % and 70 at. %, between 0.1 at. % and 60 at. %, between 0.1 at. % and 50 at. %, between 0.1 at. % and 40 at. % or between 0.1 at. % and 30 at. %.

[0060] The unit atomic percent as described herein may refer to a mole fraction of the corresponding material, where atomic percent is the relative number of particles (e.g. iridium atoms) in relation to the Total number of particles of the substance (e.g. total number of atoms of the first material). The atomic percentage can be determined using secondary ion mass spectroscopy, SIMS and / or Auger electron spectroscopy and / or X-ray photoelectron spectroscopy, XPS, can be detected (as well as, for example, via photoelectron spectroscopy, PES).

[0061] In one example, the second element may comprise at least one of the following: a metal, a semiconductor. A combination of metal and semiconductor is also possible.

[0062] The metal may be, for example, a heavy metal, a light metal, a transition metal, a noble metal, a base metal metal and / or a metal alloy.

[0063] In one example, the semiconductor comprises a semimetal and / or a compound semiconductor. The semiconductor may direct and / or indirect semiconductors. For example, the semiconductor may comprise at least one of the following: silicon (Si), Germanium (Ge), Boron (B), Arsenic (As), Gallium Arsenide (GaAs), Aluminum Gallium Arsenide (AlGaAs), Silicon Carbide (SiC), Gallium nitride (GaN).

[0064] In one example, the second element may comprise at least one of the following: tantalum, ruthenium, antimony. In In one example, the first material comprises iridium and ruthenium. In another example, the first material comprises Iridium and tantalum. In another example, the first material includes iridium and antimony. It is also conceivable that the first material comprises iridium, tantalum, and ruthenium. In another example, the first material comprises iridium, Tantalum, ruthenium and antimony.

[0065] In one example, the second element may comprise at least one non-metal.

[0066] In one example, the second element (or non-metal) may comprise oxygen and / or nitrogen.

[0067] For example, the non-metal may also comprise at least one of the following: phosphorus, hydrogen, Carbon, a halogen (e.g. bromine, fluorine, chlorine etc.).

[0068] In one example, the iridium may combine with the second element (or with the at least one second element) to form a chemical compound. The chemical compound can be, for example, a binary, ternary and / or quaternary chemical connection include.

[0069] In one example, the method may further comprise: providing a second gas comprising second molecules wherein the removal of the first material is further based at least in part on the second gas.

[0070] The second gas described herein may in this context be considered as an additive gas with respect to the substantial Etching gas (ie the first gas). The second gas can be considered as an additive gas for removing or particle beam induced etching of the first material and e.g. process parameters / results more precisely adapt (e.g. etching rate, anisotropy factor, selectivity, sidewall angle, surface roughness, etc.). the features described herein for providing the first gas may also be used for providing the second Gases apply, and vice versa.

[0071] In one example, a dipole moment of the second molecules may comprise a value between 1.6 D and 2.1 D, preferably between 1.7 D and 2 D, particularly preferably between 1.8 D and 1.95 D, most preferably between 1.82 D and 1.9 D.

[0072] The inventors have recognized that molecules with such dipole moments when removing the first material can be advantageous. Particle beam-based removal usually requires a defined (local) Gas concentration is required over a certain period of time in order to allow the removal reaction to proceed in a defined manner. However, due to chemical and / or physical interactions during the removal of the first material, change the defined (local) gas concentration to a technically undesirable extent. This is particularly the case with the Using a more complex gas mixture comprising at least two gases (e.g. the first and the second gas) of This means increased demands on maintaining the defined (local) For example, a (local) depletion of the second gas (and / or the first gas) within the working area, so that the removal of the first material in an undesirable The inventors have recognized that using second molecules with the The dipole moments mentioned herein provide optimized conditions for the design of the defined (local) gas concentration at using the first and second gases. This also allows the removal of the first material be specifically optimized.

[0073] In one example, the method comprises considering the dipole moment of the second molecules as Parameters in the removal of the first material. For example, the dipole moment of the second molecules can Define process parameters (e.g. a gas flow rate of the first and / or second gas) during removal. For example, the gas flow rate can be selected depending on the dipole moment.

[0074] In one example, the method comprises providing the first gas and the second gas at least For example, the first gas and the second gas can be released into the environment of the work area or into the surroundings of the object, e.g. during the removal of the first material. This may further comprise that during the removal (at least partially) a first gas flow of the first gas and a second gas flow of the second gas, so that the presence of both gases in the environment of the work area / object is ensured. For example, it may be possible that the first and second Gas flow is essentially identical. However, in other examples, they may also be different. The simultaneous provision of the first and second gases may further comprise the first gas flow and the second gas flow rate (when removing the first material) can be varied.

[0075] In one example, the method comprises providing the first gas and the second gas at least For example, removing the first material may require that Process step of removing only one of the two gases in the environment of the work area / object. For example, at the beginning of the removal of the first material, it may be necessary to initially only remove the first Gas (or the second gas) is introduced into the environment of the work area / object. The second Gas (or the first gas) may be added or made available at a later time. It is also conceivable that that during the removal, a gradual change is made between the (exclusive) provision / introduction of the first gas (without the second gas) and the (exclusive) provision / introduction of the second gas (without the first gas). Furthermore, it is also possible that a process end of the removal of the first material is the exclusive Providing / introducing one of the two gases. For example, it is conceivable that a process end is exclusive provision / introduction of the second gas is defined.

[0076] In one example, the second molecules may comprise water, HO, and / or heavy water, DO. 2 2 for the removal of the resistant first material water and / or heavy water as an advantageous additive gas For example, with such an additive gas, the selectivity of the removal of the first material, compared to another material. In a particularly advantageous example, the Process XeF as the first gas and HO as the second gas. In another example, the second molecules of the 2 2 second gas may also include semi-heavy water, HDO. In another example, the second gas (or molecules) may be an oxygen-containing component, a Halide and / or a reducing component. The oxygen-containing component can be, for example, a oxygen-containing molecule. For example, the oxygen-containing component may comprise at least one of the following: Oxygen (O ), Ozone (O ), Hydrogen peroxide (HO ), Nitrous oxide (NO ), Nitric oxide (NO ), Nitrogen dioxide 2 3 2 2 2 (NO ), nitric acid (HNO ). The halide can, for example, be at least one of the following: Cl , HCl, XeF , HF, I , HI, Br 2 3 2 2 2 , HBr, NOCl, NOF, ClNO , FNO , PCl , PCl , PF , PF . The reducing component may comprise a molecule that 2 2 2 3 5 3 5 has a hydrogen atom. For example, the reducing component may comprise at least one of the following: H , NH , 2 3 (NH ) , CH . In one example, the second gas may comprise water (and / or heavy water) and nitrogen dioxide. 2 2 4

[0077] In one example, the first material may be selectively removed so that a second material of the object in the is not substantially removed. For example, the method can be designed such that removal according to the invention (e.g. based on particle beam induced etching) a selectivity of the removal (e.g. B. an etch selectivity) of the first material compared to the second material. The selectivity can be, for example, allow the second material to be removed at a lower removal rate than the first material when the second material is exposed to the process. Accordingly, the process may include a defined selectivity is adjusted (e.g. an increased etch selectivity). This can be achieved, for example, by a suitable choice of the first and / or second gas, as well as suitable gas parameters of the first and / or second gas (e.g. gas flow, gas pressure, gas concentration, etc.) can be ensured. For example, the choice of the second gas (e.g. water and / or heavy water as described herein) and the gas parameters of the second gas are used to determine the Selectivity of removing the first material over the second material. The method can further in such a way that there is essentially no physical / chemical stress on the second material.

[0078] In one example, the second material may be a material at any location of the object for lithography and a material within the working area (described herein). Furthermore, the second material is a Material conceivable, which in principle the material removal exposed to the effects of the process. For example, this may include the second material being exposed to the process exposed to the first (or second gas) and / or in the immediate vicinity of the particle beam For example, the second material can be in contact with the first material or mechanically bonded to the first material. be coupled (e.g. indirectly via an intermediate material). In this case, it is conceivable that when removing of the first material is accompanied by an exposure of a surface of the second material, so that the second material of the material-removing effect of the process. According to the invention, the removal of the second material can be counteracted by the selectivity of the process. The second material can be used in a typical Application of the method can be, for example, a part of a layer of the object that is connected to the first material (directly or indirectly) adjacent.

[0079] For example, the object may have a characteristic layer structure in which a cover layer on a reflective layer stack (e.g. a Bragg mirror). The characteristic layer structure can also comprise a buffer layer adjacent to the covering layer. In addition, the buffer layer may have a In one example, a part of the absorption layer may be the first material (to be removed) of the process. The process can accordingly be designed with such selectivity that the second material is the material of the buffer layer, the material of the cover layer and / or the material of the reflective layer stack. In one example, the selectivity is designed such that the second material explicitly includes the material the top layer of the object's reflective layer stack. This can allow the reduced Ablation rate of the cover layer, the process can be terminated specifically without damaging the reflective layer stack The top layer can therefore act as a removal stop (e.g. etch stop), so that damage to the reflective layer stack, which would be accompanied by damage to the optical properties of the object, can be prevented.

[0080] The method can be carried out in such a way that the selectivity of the removal of the first material compared to the second material is at least 2:1. In one example, the selectivity of removing the first material is compared to the second material at least 7:1, preferably at least 15:1, more preferably at least 25:1, on most preferred at least 50:1.

[0081] In one example, the method may comprise removing at least one intermediate material disposed between the first material and the second material. As described herein with respect to the characteristic layer structure As described, the intermediate material may, for example, comprise part of the buffer layer of the object. conceivable that the at least one intermediate material forms part of the buffer layer and part of the covering layer of the object The intermediate material does not necessarily have to have the properties of the first material mentioned here (or the second material).

[0082] In one example, the method comprises removing at least one surface material of the object.

[0083] The surface material may, for example, comprise a material of the object which imparts a characteristic to the first gas and / or second gas, as well as the particle beam accessible surface (e.g. a freestanding surface of the object). The surface material can comprise any material and is not limited to the substances and The material content of the first or second material is limited. The surface material can be removed, for example, to to expose (at least partially) the first material arranged underneath for the method according to the invention. The surface material can, for example, be based on the characteristic layer structure of the object described here. be part of a surface layer adjacent to the absorption layer (e.g. opposite the buffer layer). Surface layer may include, for example, an anti-reflection layer, an oxide layer, a passivation layer.

[0084] In one example, the method is carried out in such a way that a defect of the object is repaired. For example, the method can involve repairing an opaque defect in the object.

[0085] An opaque defect can be a faulty spot on the object for lithography, which actually The design of the object should not be opaque, ie clear (e.g. translucent or designed in such a way that no targeted Absorption for a radiation of a specific wavelength, e.g. the lithographic wavelength). An opaque defect can also be understood as a defective spot on the object, which, according to the design of the object, does not contain any material of a pattern element, but an (unwanted) material is present at that location. The existing (Unwanted) material can, for example, include a material of the pattern element, whereby it is also conceivable that this another (unwanted) material which has a radiation-absorbing and / or phase-shifting effect.

[0086] A clear defect, on the other hand, is a faulty spot on the object for lithography, which was actually intended according to the design of the object should be opaque (e.g. impermeable or strongly absorbing for a radiation of a certain wavelength, e.g. the lithographic wavelength). A clear defect can also be considered a faulty spot on the object, which, according to the design of the object, should contain a material of a pattern element, but there is no material at that point is present or the material of the pattern element is not present. In particular, opaque can be defined with respect to a Lithography process for which the object can be used. For example, the object can use an EUV mask for lithography for an EUV lithography process, where opaque in this case refers to the lithographic wavelength of 13.5 Nanometers. It is also conceivable that opaque refers to a DUV lithography process (e.g. at 193 nanometers or 248 nanometers lithographic wavelength), an i-line lithography process (at e.g. 365 nanometers lithographic wavelength), as well as any other lithography process depending on the object. Furthermore, an opaque defect can be, for example, B. include a defective area that has opaque material of a layer of a lithographic mask (e.g. this can a layer that is designed as a layer for an opaque pattern element of the object). The method can include removing the first material in such a way that the defective area is no longer opaque.

[0087] For example, the repair of the defect may initially involve locating the defect (e.g. via a scanning electron microscope, an optical microscope, etc.). The working area required for removing the first material used, based on at least one characteristic of the localized defect (e.g. based on a position, shape, size, type of defect, etc.). Fixing the defect of the object can further include creating a repair shape that includes the defect. The repair shape may, in one example, be The workspace for the methods mentioned herein may be, for example, a pixel grid which allows for the localization of a defect location. The pixel grid can For example, it can be designed to follow the contour of the defect, so that each pixel of the pixel grid is essentially corresponds to a location of the defect and thus represents a defect pixel. In another example, the pixel grid a fixed geometric shape (e.g. a polygon, a rectangle, a circle, etc.) that completely encompasses the defect, where Not every pixel necessarily represents a location of the defect. The pixel grid can include defect pixels that location of the defect, and non-defect pixels that correspond to a location that is not part of the defect In one example, the method comprises directing the particle beam during the generation of the material at least a defect pixel of the pixel grid of the repair shape. Furthermore, the particle beam can be configured such that that when removing the first material (or removing the second material) it is directed at each defect pixel This ensures that the removal of the first (or second) material is applied locally to the Defect pixel is limited and therefore only the defect is processed.

[0088] In a further example, the method can be used in a processing of the object which The processing as well as the local material production can be carried out, for example, within the framework of a Defect processing of the object (e.g. when repairing a clear defect and / or a defective area, a removal of a particle, etc.). Even in such a process, the method described herein can be used for be used.

[0089] In one example, the object comprises an EUV mask and / or a DUV mask. For example, the object described herein The characteristic layer structure described corresponds to the layer structure of an EUV mask.

[0090] In one example, the particle beam may comprise an electron beam. For example, the particle beam described herein described removal may include electron beam induced etching within the process (e.g. known as the term (F)EBIE - (focused) electron beam induced etching).

[0091] However, it is also conceivable that the particle beam comprises an ion beam (e.g. gallium ions, helium ions, etc.). For example, the removal of the first material can be based on ion beam induced milling / etching (e.g. focused ion beam (FIB) milling.

[0092] Furthermore, it is also conceivable to use several particle beams as the particle beam.

[0093] In one example, the method may further comprise: determining an endpoint of a removal of a material based at least in part on detecting electrons emitted from the working area. The detected electrons may include, for example, primary electrons and / or secondary electrons.

[0094] In one example of the method, the removal of a material may be carried out at least partially via a predetermined For example, the time period for a parameter space of the procedure can be determined experimentally (e.g. by carrying out the procedure with several time periods to Determination of when a material (e.g. with a certain thickness) is removed). For example, the predetermined duration of a predetermined thickness of the material.

[0095] In one example, the method may be carried out in such a way that a side wall angle (of an edge, e.g., of a structure) of the first material with respect to a plane of another material (e.g. with respect to a plane of the second material) The side wall angle can, for example, be adjusted to the level of a - under the first material - layer, or also to the (planar) plane of the object.

[0096] For example, the side wall angle may be at least 70°, at least 74°, at least 78°, at least 80°, at least 85°. For example, the sidewall angle can be a maximum of 90°, a maximum of 88°, a maximum of 85°, or a maximum of 80°. For example, the sidewall angle may comprise a value between 70° to 90°, preferably between 74° to 90°, more preferably between 78° to 90°, most preferably between 80° to 90°.

[0097] In one example, the method of the first aspect comprises directing the particle beam at least partially on a Acceleration voltage of less than 3 kV, preferably less than 1 kV, more preferably less than 0.8 kV, at most preferably less than 0.6 kV. In one example, the particle beam is further based on a Acceleration voltage of at least 0.1 kV, preferably at least 0.15 kV, more preferably at least 0.2 kV, at most preferably at least 0.3 kV. In one example, the accelerating voltage of the particle beam comprises a Value that is between 0.1 kV and 3 kV, between 0.15 kV and 1 kV, between 0.2 kV and 0.8 kV, or between 0.3 kV and 0.6 kV.

[0098] In these ranges of acceleration voltage, the method of the first aspect can advantageously be (as described herein). For example, in this parameter space, the first material can be advantageously be removed.

[0099] Furthermore, it is also conceivable that the particle beam is at an acceleration voltage of less than 30 kV, preferably less than 20 kV. In one example, an accelerating voltage between 3 kV and 30 kV can be used to imaging purposes within the scope of the procedure (e.g. when taking an image before or after the removal and / or taking a picture during removal).

[0100] In one example, the particle beam comprises a current of at least 1 pA, at least 5 pA, at least 10 pA, at least 20 pA, at least 25 pA, at least 50 pA.

[0101] In one example, the particle beam comprises a current of maximum 100 pA, maximum 80 pA, maximum 60 pA or a maximum of 50 pA.

[0102] In one example, the particle beam comprises a current having a value between 1 pA to 100 pA, preferably between 5 pA to 80 pA, most preferably between 10 pA to 60 pA.

[0103] In one example, the method is carried out in such a way that the exposure of the second material (via the removal of the first material) a surface of the second material has a square roughness, RMS, of less than 3 nm, preferably less than 2 nm, more preferably less than 1 nm, most preferably less than 0.5 nm.

[0104] A second aspect relates to an object for lithography, wherein the object is produced by a method of the first aspect For example, a visual examination of the object can be used to determine whether the object has been a process of the first aspect. For example, the object for lithography can initially be optical examination must have been carried out or be carried out (e.g. as part of a defect qualification of the object, e.g. following the manufacture of the object and / or when the object is introduced into a Semiconductor plant). The optical examination can be based on an optical or particle-optical microscope (e.g. on a mask metrology device, a mask microscope) and, for example, include image recording. Processing the object according to an example of the first aspect following the initial investigation can first material must have been removed as described herein. The removal of the first material may be achieved by repeated visual examination (e.g. as part of a repair check or a renewed defect qualification) The proof can be obtained, for example, by comparing the initial optical examination with the repeated optical Investigation (e.g. by comparing the corresponding images). Furthermore, the evidence of the The method can also be based on a material analysis of the object (e.g. Auger spectroscopy, X-ray spectroscopy, etc.), which is carried out in addition to the initial or repeated optical examination.

[0105] A third aspect relates to a method for processing a semiconductor-based wafer comprising: lithographic Transferring a pattern associated with an object for lithography on the wafer, wherein the object is produced by a method of the first aspect was edited.

[0106] The lithographic transfer may comprise a lithography process for which the object is designed (e.g. EUV Lithography, DUV lithography, i-line lithography, etc.). For example, the method of the third aspect may comprise providing a source of electromagnetic radiation (e.g. EUV radiation, DUV radiation, i-line radiation, etc.). may include providing a developable resist layer on the wafer. The lithographic transfer may Furthermore, it may be based at least in part on the beam source and the provision of the developable resist layer. The pattern is imaged onto the lacquer layer (in a transformed form) using the radiation from the beam source.

[0107] The methods described herein can be deposited in writing, for example, via a digital file, analogue (e.g. in paper form), in a user manual, in a recipe (which e.g. is contained in a device and / or a computer of a semiconductor factory). Furthermore, it is conceivable that when executing one of the procedures described here, a written record is created. The record can, for example, enable the execution of the procedure, as well as its details (e.g. the recipe) to be carried out at a later date can be demonstrated (e.g. in the context of a defect assessment, a material review board, an audit, etc.). The protocol may, for example, comprise a log file (ie log file) stored in a device and / or computer can be deposited.

[0108] A fourth aspect relates to a computer program comprising instructions for carrying out a method of first aspect and / or the third aspect.

[0109] A fifth aspect relates to an apparatus for processing an object for lithography comprising: means for Providing a first gas; means for providing a particle beam on the object. The device may comprise a memory comprising a computer program which, when executed, causes the device to perform a method of the first aspect.

[0110] For example, the device may comprise means for executing a computer program (e.g., a computer system, a computing unit, etc.).

[0111] For example, the computer program may comprise a computer program of the fourth aspect, wherein said computer program is based on the device is programmed. The device can, for example, store instructions of the computer program, wherein the stored instructions are executed via the computer system, and the corresponding means of cause the device to carry out the method of the first aspect.

[0112] The device may, for example, (essentially) correspond to a scanning electron microscope having a Electron beam as a particle beam on the object. The scanning electron microscope can be configured be capable of providing the gases described herein. The first gas (and / or the second gas) can, for example, be be stored in appropriate storage containers and via a gas supply system (e.g. a gas line with a gas nozzle) directed to a working area of ​​the object. The device can also have a control system which is set up in such a way as to carry out the procedure automatically.

[0113] Alternatively, it is also possible that the computer program is stored elsewhere (e.g. in a cloud) and the device only has means for receiving instructions resulting from the execution of the program Either way, this can, for example, make it possible for the process to be automated or self-sufficient can take place within the device. This way, the intervention by an operator, for example, can be minimized, so that the Both costs and complexity in processing masks can be minimized. 4. Short description of the characters

[0114] The following detailed description provides technical background information as well as Embodiments of the invention are described with reference to the figures, which show the following: Fig. 1 shows a schematic top view of an example repair situation of an object for the Lithography. Fig. 2 shows a schematic diagram of an exemplary method of the invention. Fig. 3a-c illustrates schematically in a cross-section exemplary processes in a process of Invention. Fig. 4 shows a schematic view of an exemplary device of the invention. 5. Detailed description of possible embodiments

[0115] Fig. 1 schematically illustrates in a plan view an exemplary repair situation of an object for lithography. The object for lithography can comprise a lithographic mask, which is used for any lithography process is suitable (e.g. EUV lithography, DUV lithography, i-line lithography, Nanoimprint lithography, etc.). In one example, the lithographic mask may be an EUV mask, a DUV mask, an i-line Lithography mask and / or a nano-imprinting stamp. Furthermore, the object for lithography can comprise a binary mask (e.g. a chrome mask, an OMOG mask), a phase mask (e.g. a chrome-free phase mask, an alternating Phase mask (e.g. a rim phase mask)), a halftone phase mask, a tritone phase mask and / or a reticle (e.g. B. with pellicle). The lithographic mask can be used, for example, in a lithography process for the production of semiconductor chips are used.

[0116] The object for lithography may, for example, include (undesired) defects. For example, a defect in the production of the object. Furthermore, a defect can also be caused by (lithographic) processing of the object, a process deviation during (lithographic) processing, transport of the object, etc. Due to the usually costly and complex production of an object for lithography, the defects are therefore usually repaired.

[0117] In the embodiments described herein, for illustrative purposes, reference is often made to an EUV mask as an example of an object for lithography. However, instead of the EUV mask, any Object conceivable for lithography (as described here, for example).

[0118] Fig. 1 can schematically show in a plan view two local states D, R of a section 1000 of an EUV mask in The section 1000 shows a part of a pattern element PE of the EUV mask. The pattern element PE can also be used as a pattern element (or pattern structure) of the EUV mask The pattern element PE can be a part of a designed pattern, which has a lithographic process, for example, onto a wafer. The local state D shows an opaque Defect 1010 occurs adjacent to the pattern element PE. The opaque defect 1010 can be caused, for example, by excess (opaque) material which should not be present at the defect site according to the mask design. Excess (opaque) material can correspond, for example, to an opaque material of the pattern element PE, as well as to a any other material of a layer of the pattern element PE (as described herein). Referring to Fig. 1 (Condition D) a defect-free pattern element PE in section 1000 would have to have a rectangular shape, whereby it is clear that This target state is not present due to the opaque defect 1010. A repair process RV is therefore used to excess (opaque) material in the area of ​​the opaque defect 1010 is removed, so that a repaired state R of the Pattern elements PE can be generated. Thus, in state R it is shown that in the original defect area 1020 (i.e. i.e. at the original location of the opaque defect) no opaque effect occurs and no excess (opaque) Material is no longer available. By removing the defect 1010, the desired rectangular shape of the Patternelements PE restored after a repair operation.

[0119] During use in lithography devices or lithography processes, a lithographic mask be exposed to extreme physical and chemical environmental conditions. This applies in particular to the Exposure of EUV masks (as well as DUV masks, or other masks as described herein) during a corresponding lithography process, whereby in particular the opaque material of a pattern element PE is exposed to these influences can be exposed to strong radiation. For example, during EUV exposure, a hydrogen plasma containing hydrogen radicals can be released which, among other things, attack the opaque material of the pattern element PE and cause a material-changing and / or - removing effect. Further damaging influences can occur during the EUV lithography process and Damage to the mask material includes, for example, chemical and physical Change of the material by (EUV) radiation, temperature, as well as a reaction with hydrogen or another reactive hydrogen species (e.g. radicals, ions, plasma, etc.). The change in the material can also be ® Reaction with purge gases (e.g. N2, extreme clean dry air - XCDA, noble gases, etc.) in conjunction with the exposure radiation (e.g. EUV radiation, DUV radiation). Damage to the material can also be caused by downstream processes (e.g. mask cleaning) are created or intensified. The downstream processes For example, the opaque layer damaged by chemical / physical reactions during the exposure process The material of the pattern element PE can also be attacked and the damage can be increased.

[0120] Therefore, a chemically resistant material can be used as the opaque material of a pattern element PE In particular, iridium-containing materials (as described herein) may be used for Resistance as a resistant material of the pattern element PE at an EUV mask. The iridium-containing materials can, for example, be of the form Ir Z (a, b ≥ 0, Z: one or away several other elements with the stoichiometric coefficient b) applicable to the respective element. Z can be a metal, non-metal, semi-metal, alkali metal (e.g. Li, Na, K, Rb, Cs). Furthermore, Z can be a Alkaline earth metal (e.g. Be, Mg, Ca, Sr, Ba), an element of the 3rd main group (e.g. B, Al, Ga, In, Tl), an element of the 4th main group (e.g. C, Si, Ge, Sn, Pb), an element of the 5th main group (e.g. N, P, As, Sb, Bi). Furthermore, Z a chalcogenide (e.g. O, S, Se, Te), a halogen (e.g. F, Cl, Br, I) a noble gas (atom) (e.g. He, Ne, Ar, Kr, Xe), an element of Subgroups (e.g. Ti, Hr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Re, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Hg).

[0121] However, this type of resistant (opaque) material of a pattern element PE or an EUV mask can Repair process RV of an opaque defect 1010 significantly complicate, since during the repair process the resistant (opaque) material should be specifically removed.

[0122] Fig. 2 shows a schematic diagram of an exemplary method 200 of the invention. The method 200 can be used to remove material from an EUV mask. In particular, the method can be used 200 be used to remove material from an opaque defect 1010 as part of a repair process.

[0123] The method 200 may comprise providing 210 a first gas having first molecules. The first gas can include, for example, XeF as the first molecules. Furthermore, other gases are also conceivable as the first gas, such as 2 described herein.

[0124] For the method 200, further molecules are also suitable as first molecules of the first gas. For example, Both polar and non-polar triatomic molecules are conceivable. The first molecules can also include molecules that under suitable reaction conditions can be split into chlorine or fluorine radicals and / or further, for example, into another nonpolar species are cleavable.

[0125] Furthermore, the method 200 may include providing 220 a particle beam on the object for lithography comprise removing a first material of the object based at least in part on the first gas. The first Material may include iridium. The method 200 may further include an electron beam as the particle beam, so that an electron beam-induced etching of the first material can be enabled according to method 200.

[0126] The first material may in particular correspond to the resistant (opaque) material of the EUV mask (as described herein described), which is to be removed as part of the repair of an opaque defect.

[0127] The method 200 may further comprise providing a second gas as an additive gas, which Etching process supported (e.g. with regard to etching selectivity, etching rate, anisotropy factor, etc.).

[0128] In particular, in the electron beam induced etching, XeF can be used as the first gas and HO as the additive gas (ie 2 2 Water (vapor)) may be used in the process 200. Furthermore, the second molecules may be a Dipole moment between 1.6 D and 2.1 D, preferably between 1.7 D and 2 D, more preferably between 1.8 D and 1.95 D, at most preferably between 1.82 D and 1.9 D. It is also conceivable that HO is mixed with nitrogen dioxide (or a 2 other oxidative gas) is combined as an additive gas.

[0129] Fig. 3a-c schematically illustrate in a cross-section exemplary processes of the method 200, which in can take place as part of a repair of a defect in an object for lithography.

[0130] Fig. 3a schematically presents an exemplary characteristic layer structure of a reflective lithographic mask for the EUV wavelength range (ie an EUV mask). The exemplary EUV mask can be used for example for an exposure wavelength in the range of 13.5 nm. The EUV mask can be a substrate S made of a material with a low thermal expansion coefficient, such as quartz. Other dielectrics, Glass materials or semiconducting materials can also be used as substrates for EUV masks.

[0131] On the substrate S, a deposited multilayer film or a reflective Layer stack ML, which has e.g. 20 to 80 pairs of alternating molybdenum (Mo) and silicon (Si) layers, which are also called MoSi layers. The individual layers of the multilayer film ML can differ in their refractive index, creating a Bragg mirror that reflects incident radiation (e.g. EUV radiation) can reflect.

[0132] In order to protect the reflective layer stack ML, a capping layer D (also called ´´capping layer´´) For example, it can be applied to the top layer of the reflective layer stack ML. The cover layer D can the reflective layer stack ML from damage caused by chemical processes during the manufacture and / or use of the EUV mask (e.g. during a lithographic process).

[0133] The cover layer D may comprise (elemental) ruthenium, as well as elements or compounds of elements, which increase the reflectivity at 13.5 nm wavelength by no more than 3%. Furthermore, the top layer D can contain Rh, Si, Mo, Ti, TiO, TiO , ruthenium compounds, ruthenium alloys, ruthenium oxide, niobium oxide, RuW, RuMo, RuNb, Cr, Ta, nitrides, 2 as well as compounds and combinations of the aforementioned materials. The cover layer may further comprise of the following materials include: RuRh, RuZr, RuZrN, RuNbN, RuRhN, RuV, RuVN.

[0134] On the cover layer D there can be several layers, which for example are the layers of the pattern element (ie Pattern element layers). The pattern element layers may comprise a buffer layer P, a Absorption layer A and / or a surface layer O. The properties of the pattern element layers (e.g. an intrinsic material property of a pattern element layer, a layer thickness of a pattern element layer, etc.) and the geometry of the pattern element PE formed therefrom can be designed to have an opaque effect with respect to the exposure wavelength of the EUV mask. For example, the pattern element PE can be designed in such a way that it opaque (i.e. impermeable to light or strongly light-absorbing) is resistant to light radiation with a wavelength of 13.5 nm. The pattern element layers can correspond to the layers of the opaque defect 1010, whereby the opaque defect 1010 does not necessarily have to have all pattern element layers. For example, the opaque defect 1010 only the buffer layer P and the absorption layer A.

[0135] The buffer layer P can be located on the cover layer D. Furthermore, the absorption layer A can be located on the buffer layer P. The absorption layer A can be effectively designed to absorb the radiation of lithographic wavelengths (as described herein). Accordingly, absorption layer A can be the main contributor to a opaque effect of the pattern element (or the opaque defect 1010). The optical properties of the Absorption layer A can be described, for example, by a complex refractive index, which has a phase-shifting contribution (i.e. n) and an absorption contribution (i.e. k). For example, n and k can be considered as intrinsic material properties of the absorption layer. Only certain chemical elements and / or Compounds of chemical elements have for the corresponding lithography process (e.g. an EUV lithography process) advantageous phase-shifting and / or absorptive properties. Fig. 3a shows an example of the layer thickness d of the Absorption layer A. The layer thickness d of the absorption layer A (as well as a layer thickness of another layer of the mask) is determined, for example, along a normal vector in relation to the planar plane of the mask. In principle, conceivable that the absorption layer A comprises several absorption layers, which for example consist of different materials Furthermore, the surface layer O can be located on the absorption layer A. The surface layer O can an anti-reflection layer, oxidation layer and / or passivation layer. In addition to the absorption layer A The buffer layer P and / or the surface layer O can also be used for absorption or opaque effect of the Pattern elements PE or the opaque defect 1010.

[0136] In principle, each of the pattern element layers described herein may comprise the mentioned resistant first material (ie iridium-containing material). For example, the absorption layer A usually contains iridium. The first material of the Method 200 can therefore comprise a material of the absorption layer A. Furthermore, however, the buffer layer P or the surface layer O may comprise iridium and thus constitute the first material of the process 200.

[0137] Fig. 3b shows a result of an exemplary method 200 for removing a portion of the absorption layer A. In this example, the absorption layer A is designed as the first material of the method 200. Initially, a Part of the surface layer O can be removed. For example, this can be done analogously to the method 200 via a Electron beam induced etching must be carried out in a separate step. The removal of the surface layer does not have to forced with the first and / or second gas (as described herein). It is also conceivable that the electron beam induced etching is designed exclusively for the removal of the surface layer O (e.g. with a Etching gas which is adapted to the material of the surface layer O). After removing the surface layer O a part of the absorption layer A can then be removed as the first material in the process 200 (e.g., to repair an opaque defect). Fig. 3b illustrates a selective electron beam induced etching of the absorption layer A relative to the buffer layer P. Accordingly, the method 200 can be set such that the Etching rate of the absorption layer A is increased compared to the etching rate of the buffer layer P. For example, the Etching selectivity can be adjusted via the properties of the second gas in the method 200 (e.g. via a suitable choice of the second gas (e.g. water), or the gas flow rate of the second gas). Furthermore, the etching selectivity can also be determined by the properties of the first gas (e.g. by selecting the first gas (e.g. XeF ), or the gas flow rate of the 2 first gas). In this example, the buffer layer P acts as an etch stop via the selected etch selectivity. In the Example of Fig. 3b, the buffer layer P can represent the second material which is essentially not removed.

[0138] Fig. 3c shows another result of an exemplary method 200 for removing a part of the Absorption layer A. Initially, a part of the surface layer O can be removed (as described herein). After After removing the surface layer O, a part of the absorption layer A can then be used as the first material in the within the framework of the method 200. In this case, a part of the buffer layer P can also be etched as an intermediate material Accordingly, the method 200 can be set such that the etching rate of the absorption layer A, as well as the Etching rate of the buffer layer P is increased compared to the etching rate of the cover layer D. The etching rate of the absorption layer A can be in the same order of magnitude as the etching rate of the buffer layer P. The etching selectivity can be determined as described As shown in Fig. 3c, this allows for selective electron beam induced etching the absorption layer A and the buffer layer P opposite the cover layer D. In this example, therefore, The cover layer D acts as an etch stop via the selected etch selectivity. In the example shown in Fig. 3c, the cover layer D can second material which is not substantially removed.

[0139] In one example, the surface layer O is not removed separately, but via the same process used for the local removal of the absorption layer A (or the absorption layer A and the buffer layer P) in the context of a Procedure 200 is applied.

[0140] Furthermore, it should be mentioned that the parameter space (e.g. gas parameters of the first / second gas, Particle beam parameters) of the method 200 on the one hand from the layer currently processed (with the particle beam) This can, for example, correspond to a gradual removal of layers (or materials), where for each Layer (or materials) the parameter space of the method 200 is adapted. However, it is also possible that the Parameter space of the method 200 does not depend on the layer currently being processed (with the particle beam). This approach allows, for example, several layers (or materials) to be removed one after the other.

[0141] It should also be mentioned that the first material (comprising iridium) can be any layer material of the EUV mask For example, the top layer D may comprise iridium. The approach described herein may also such iridium-containing cover layer D can be etched.

[0142] The method 200 (or the method of the first aspect) can be carried out via the inventive method described herein device. In one example, the device comprises a mask repair device for repairing or processing of lithographic masks. The device can be used to detect mask defects and to repair or remedy them. The device may include parts such as those described in US 2020 / 103751 A1 (see corresponding Fig. 3A). The device can, for example, be a control unit which may, for example, be part of a computer system. The device may, in one example, be configured such that so that the computer system and / or the control unit, the process parameters of the method disclosed herein of first aspect. This configuration can enable the device according to the invention mentioned herein The process can be targeted or automated, e.g. without manual intervention. This configuration of the device can be realized or enabled, for example, via the inventive computer program described herein.

[0143] Fig. 4 shows a schematic section of an exemplary device 400 according to the invention. The device 400 can e.g. be configured to implement the method 200 or a method of the first and / or second aspect of the invention For example, the device may have a corresponding computer program (as described herein) be programmed.

[0144] In one example, the apparatus 400 of Figure 4 includes a mask repair device for repairing or Processing lithographic masks. The device 400 can be used, for example, to locate and repair or fix them.

[0145] The exemplary device 400 of Fig. 4 may be, for example, a scanning electron microscope (SEM for Scanning Electron Microscope) 101 for providing a particle beam, which in this example is an electron beam 409. An electron gun 406 can generate the electron beam 409, which is formed by one or more beam-forming Elements 408 as a focused electron beam 110 can be directed onto a lithographic mask 402 which is a sample table 404 (or stage, chuck). Furthermore, the scanning electron microscope can be used to Parameter / Properties of the electron beam can be adjusted (e.g. acceleration voltage, dwell time, current, Focusing, spot size, etc.). The parameters of the electron beam can be defined, for example, in relation to a parameter space of the The electron beam 409 can be used as an energy source to initiate a local chemical reaction on a working area of ​​the lithographic mask 402.

[0146] This can be used, for example, for the methods described herein (e.g. for the implementation of the electron beam induced etching of the first aspect). Furthermore, the electron beam 409 can be used to record an image the lithographic mask 102. The device 400 can have one or more detectors 414 for Detection of electrons (e.g. secondary electrons, backscattered electrons).

[0147] To perform the respective methods mentioned herein, the exemplary apparatus 400 of Fig. 4 have at least two storage containers for at least two different processing gases or precursor gases. The first storage tank G1 can store the first gas. The second storage tank G2 can store the second gas. In some examples, the storage tanks G1 and G2 can be temperature-controlled independently of each other. The second gas can also be considered an additive gas. Furthermore, in the exemplary device 400, each reservoir G1, G2 has its own gas supply system 432, 447, which is connected to a nozzle near the point of impact of the electron beam 410 can end on the lithographic mask 402. Each reservoir G1, G2 can have its own Control valve 446, 431 to control the amount of the corresponding gas provided per unit of time, ie the Gas flow of the corresponding gas, to be controlled or regulated. This can be done in such a way that the Gas flow rate is specifically adjusted at the point of impact of the electron beam 410. Furthermore, the Device 400 in one example may have further storage containers of additional gases which are suitable for the method of the first aspect as one or more (additive) gases can be added (e.g. oxidizers, reducing agents, halides as described herein). The device 400 of Fig. 4 may include a pumping system for generating and Maintain a required pressure in the process chamber 485.

[0148] The device 400 may further comprise a control unit (or regulating unit) 418, which may be part of a Computer system 420. In one example, the device 400 may be configured such that the Computer system 420 and / or the control unit 418, the process parameters of the methods disclosed herein This configuration can enable the methods according to the invention mentioned herein targeted, as well as automated, e.g. without manual intervention. This configuration of the device 400 can e.g. be realized or enabled via the inventive computer program described herein.

[0149] For example, the device 400 may include a memory 450 on which the computer program of the fourth aspect. For example, the computer system 420 can cause the instructions stored in the memory 450 are executed so that a first material comprising Iridium is removed according to the invention via the device (with the necessary process parameters). The device can e.g. include an interface. The interface can contain the information that a procedure is to be executed where the first material (described here) is to be removed. For example, an input via the Interface by an operator that an iridium-containing material is to be removed. Based on this Information may cause the device to retrieve the computer program of the fourth aspect from the memory 450 so that the method of the first aspect is executed. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is intended solely for This list is not part of the German patent or trademark law. Utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] US 2020103751 A1

[0142]

Claims

1. A method for processing an object for lithography (402) comprising: Providing a first gas (G1) comprising first molecules; Providing a particle beam (409) on the object for removing a first material (A) of the object based at least partially on the first gas, wherein the first material comprises iridium.

2. The method of claim 1, wherein the first gas is provided locally on the object.

3. The method of claim 1 or 2, wherein the first material comprises a layer material of the object.

4. Method according to one of claims 1-3, wherein the first material is a layer material of a pattern element of the object includes.

5. Method according to one of claims 1-4, wherein the first material is a radiation-absorbing and / or a phase-shifting layer material of the object.

6. The method according to any one of claims 1-5, wherein the first molecules comprise a halogen atom.

7. The process according to claim 6, wherein the halogen atom comprises at least one of the following: fluorine, chlorine, bromine, iodine.

8. The method of any one of claims 1-7, wherein the first molecules comprise a halogen compound.

9. The method according to any one of claims 1 to 8, wherein the first molecules comprise a noble gas halide.

10. The method according to claim 9, wherein the noble gas halide comprises at least one of the following: xenon difluoride, XeF , 2 Xenon dichloride, XeCl, xenon tetrafluoride, XeF, xenon hexafluoride, XeF. 2 4 6 11. The method of any one of claims 1-10, wherein the first material further comprises at least one second element.

12. The method of claim 11, wherein the second element comprises at least one of the following: a metal, a Semiconductor.

13. A method according to any one of claims 11 or 12, wherein the second element comprises at least one of the following: Tantalum, ruthenium, antimony.

14. The method according to any one of claims 11-13, wherein the second element comprises at least one non-metal.

15. The method according to any one of claims 11-14, wherein the second element comprises oxygen and / or nitrogen.

16. The method according to any one of claims 1 to 15, wherein the method further comprises: Providing a second gas (G2) comprising second molecules, wherein the removal of the first material further at least partly based on the second gas.

17. The method according to claim 16, wherein a dipole moment of the second molecules comprises a value ranging between 1.6 D and 2.1 D, preferably between 1.7 D and 2 D, particularly preferably between 1.8 D and 1.95 D, most preferably between 1.82 D and 1.9 D.

18. The method according to any one of claims 16 or 17, wherein the second molecules are water and / or heavy water include.

19. The method according to any one of claims 1-18, wherein the first material is selectively removed so that a second material of the object is essentially not removed.

20. The method of claim 19, wherein the method comprises removing at least one intermediate material which arranged between the first material and the second material.

21. Method according to 19 or 20, wherein the method comprises removing at least one surface material of the object includes.

22. Method according to one of claims 1 to 21, wherein the method is carried out in such a way that a defect of the object is repaired becomes.

23. The method according to any one of claims 1 to 22, wherein the object comprises an EUV mask and / or a DUV mask.

24. An object for lithography, wherein the object has been processed by a method according to any one of claims 1 to 23.

25. A method for processing a semiconductor-based wafer comprising: lithographic transfer of a pattern associated with an object for lithography onto the Wafer, wherein the object has been processed by a method according to any one of claims 1 to 23.

26. Computer program comprising instructions for carrying out a method according to one of claims 1 to 23 and / or claim 25.

27. Apparatus for processing an object for lithography comprising: means for providing a first gas; Means for providing a particle beam on the object; Memory comprising a computer program which, when executed, causes the device to carry out a method according to a of claims 1 to 23.

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