KR20060050241A - Method of producing a mask blank for photolithographic applications, and mask blank - Google Patents

Abstract

The present invention relates to a mask blank (1) for photolithography, in particular a method for producing a mask blank in EUV lithography, the following steps:

Providing a substrate (2) comprising a front portion (4) and a back portion (3);

Depositing an electrically conductive layer (5) on the back side of the substrate;

Depositing a coating on the front side of the substrate, wherein the coating comprises at least a first layer (6) and a second layer (9); And

Structuring the coatings for photolithography 6, 9; here

Each handling region 22 (22a-22c) is formed on the front portion 4 in at least one predetermined position, which handling region is not structured for photolithography by a mechanical clamp or handling device. Designed for handling of the mask blank 1, where

The first layer 6 has its respective handling area 22 such that when the mask blank 1 is adjusted from the front part, the mechanical clamp or handling device is supported by the first layer 6. (A) at 22a-22c).

Description

Method of manufacturing mask blank for photolithography and mask blank {METHOD OF PRODUCING A MASK BLANK FOR PHOTOLITHOGRAPHIC APPLICATIONS, AND MASK BLANK}

The invention is described below in connection with the method of the embodiments and the accompanying drawings, and the shapes, advantages and objects to be achieved will be derived here. The drawing is:

1 shows a schematic diagram of a mask blank according to a first embodiment of the present invention;

2 shows a schematic diagram of a mask blank according to a second embodiment of the present invention;

3 shows a schematic plan view of a mask blank according to the invention;

4 shows a partial plan view of a mask blank according to a third embodiment of the present invention;

5 shows a flowchart of the method according to the invention;

Figure 6 shows a variant flowchart of the method shown in Figure 5;

FIG. 7 shows a variant flowchart of the method shown in FIG. 6.

-Description of the main reference numerals-

Reference number

1 mask blank 2 substrate

3 Rear 4 Front

5 Electrically Conductive Back Coatings 6 Si / Mo Multilayer

7 Si / Mo multilayer 8 contacts on sidewall of substrate 2

9 buffer layer 10 absorber layer

11 Buffer layer on sidewall of substrate 2 15 Edge of substrate 2

16 cutout 20 pattern area of buffer layer 9

21 Unstructured Area 22 Handling Area

22a Closed handling area in the corner area of the mask blank1

22b center handling area

22c added handling area

FIELD OF THE INVENTION The present invention relates generally to the manufacture of mask blanks for photolithography, in particular for EUV lithography (extreme ultraviolet lithography) in the approximate 13 nm range. It relates to a method for producing an adjustable mask blank, and to a mask blank provided in this way.

In order to achieve increasingly higher integration densities in microelectronics as well as in other implementations such as microsystem technology, it is necessary to use increasingly shorter wavelengths for photolithography exposure. In the future, it is now foreseeable that wavelengths in the range of 13 nm will be used to produce structures with widths smaller than 35 nm. It is very important here to make a very accurate mask blank for photolithography. Since the smallest error in the photomask can be reproduced on each chip, the mask blank will be essentially flawless. All causes of fouling or damaging the photomask are largely eliminated during manufacturing or subsequent handling by an electrostatic chuck or mechanical clamp or handling device.

This requires very accurate techniques for the manufacture of mask blanks and for the careful care and handling of the mask blanks in order to prevent mechanical wear and particle formation as much as possible. Since photomasks are used to expose many semiconductor substrates, it is also justified that high costs are associated with the manufacture and handling of mask blanks or photomasks. In this area, no matter how small the improvement, the costs are justified. Therefore, it is not surprising that the methods used in the manufacture and handling of mask blanks or photomasks are very complicated and expensive. This is because even the smallest improvements in this field will justify high costs in integrated circuits and the like at the time of manufacture.

From the prior art, an electrostatic chuck is known for holding a semiconductor substrate provided on a back side with an electrically conductive coating. Because of the relatively large contact area between the chuck and the electrically conductive coating on the backside of the substrate, only a low pressure occurs during the holding operation, which reduces wear and mechanical stress on the backside coating. "Mask blanks for use in EUV lithography and methods for making thereof" in the German patent publication DE 103 17 792.2, filed April 16, 2003 and the corresponding United States filed April 16, 2004 by the applicant Patent application No. 10 / 825,681 discloses a mask blank having an electrically conductive backside coating. This back coating is applied by ion assisted deposition (Ion Beam Deposition (IBD), in particular ion-beam-assisted sputtering, which leads to very large wear and resistive coatings. The contents of the patent application are expressly related to the present application for the purpose of publication by reference, in particular with respect to the properties of the backside coating and the method for depositing the latter.

German patent publication DE 102 39 858 A1 (corresponding to US patent publication US 2004 041 102 A1) discloses a method and configuration for compensating for unevenness in the surface of a substrate. A multilayer reflective coating is applied to the front side of the substrate. Also disclosed is an electrically conductive backside coating of the EUV reflecting mask.

Coatings on the sidewalls of the substrate are relatively rare in microelectronics, but are not known in the area for mask blanks, especially EUV lithography. Japanese Laid-Open Patent Publication JP 03-212 916 A discloses a multilayer thin film capacitor in which a protective layer is applied on the side of an insulating substrate. Japanese Laid-Open Patent Publication JP 2001-291 661 A discloses a method of manufacturing a reflective mask in which a plurality of layers are deposited on a front side of a substrate, wherein the coating is structured on the front side by overetching. To prevent the formation of a conical structure.

US 5,756,237 discloses a method of manufacturing a projection mask in which wedge shaped grooves are formed on the back side of the mask substrate by wet etching, wherein the projection mask is a split. It is separated by splitting. During fabrication of the projection mask, the side edges of the mask substrate will be covered with a photoresist layer. However, this side edge coating is removed again.

US 2003/0031934 A1 discloses a photomask comprising a substrate on which a structure is formed. A transparent, electrically conductive layer is applied over the substrate and the pattern so that different regions of the shape are all maintained at the same potential, thereby preventing damage due to electrostatic discharge. However, the unstructured area is not used for adjustment by mechanical clamps or handling devices.

US 2002/0076625 A1 discloses a mask blank for EUV lithography, wherein the multilayer reflective layer comprises a substrate provided for reflecting EUV radiation. An absorbing layer for absorbing the EUV radiation is applied to the multilayer reflective layer.

In order to support or adjust the mask blank by a mechanical device, it is necessary to adjust the mask blank or photomask produced subsequently from the front part. In order to prevent wear, it has been proposed by the ASML company to provide a special handling area, for example on the front side of the substrate, which must remain uncoated. Therefore, in this area, the mechanical clamp or handling device will be supported directly on the mask substrate front side. Since the front surface of the mask substrate is very flat and only has a slight surface roughness, mechanical wear can also be prevented in this way while supporting or handling the mask.

This mask design is shown in FIG. As shown in Fig. 3, a pattern region 20 is provided in the front portion of the mask blank 1, in which the actual photomask is formed by structuring or patterning. Also, a number of areas for which reference numbers are not provided are designated in the corner areas. An unstructured region 21 is also provided on the front side, which surrounds the pattern region 20. Reference numerals 22a to 22c denote the separated handling areas that remain uncoated as proposed by ASML.

According to a first aspect of the invention, a method is provided for producing a mask blank for photolithography in order to produce a mask blank that can be adjusted in a simpler and more reliable manner. According to another aspect of the present invention, a method for producing a mask blank during production and also for subsequent use, which can produce cost-effectively, support and adjust for reduced wear, and reduce particle formation. This is provided. According to another aspect of the invention, such a mask blank is provided so that it can be earthed in a much simpler and more reliable manner, in particular during the adjustment and processing of the mask blank. According to another aspect of the invention, a corresponding mask blank is also provided.

According to the present invention, there is provided a method for producing a mask blank for photolithography, in particular in EUV lithography, comprising the following steps:

Providing a substrate comprising a front portion and a back portion;

Depositing an electrically conductive layer on the backside of the substrate;

Depositing a coating on the front side of the substrate, wherein the coating comprises at least a first layer and a second layer; And

Structuring the coating for photolithography;

Wherein each handling region is formed in the front portion at at least one predetermined position, the handling region is not structured for photolithography, but is designed for handling of the mask blank by a mechanical clamp or handling device, And here

The first layer is exposed to the respective handling regions such that when the mask blank is adjusted from the front portion, the mechanical clamp or handling device is supported on the first layer.

Therefore, the present invention provides that the handling of the mask blank in such a manner that the material is soft and hardly causes wear is not a case where an uncoated handling area is designated on the front of the mask blank, as suggested in the prior art. Rather, it is based on the fact that a suitable coating can be achieved when provided in the handling area. In general, the surface of the mask blank is very flat and has a low residual roughness. When found by the inventors, this surface is suitable for forming a relatively flawless and very homogeneous coating by deposition. In addition, such coatings are characterized by high planarity and low defect density, such coatings are also very wear resistant and can be subjected to relatively high stresses.

It is advantageous in that fewer process steps and / or simpler process steps can be used to form the front side coating. In particular, the front surface of the mask substrate can be processed over the entire surface in at least several process steps without the complex masking or etching techniques required to form the handling area.

According to yet another embodiment, the coating is deposited in such a way that the sidewalls of the substrate can be covered by at least some areas, wherein the coating is electrically conductive. The mask blank may also be electrically contacted on the side portion. This is desirable, for example, to ground the mask blank to prevent unwanted charge caused by, for example, irradiance and / or to maintain the mask at a defined potential. This is because the mask blank can be maintained in a more reliable and reproducible manner by an electrostatic chuck. This ground from the side of the mask blank can also be used to prevent the generation of uncontrolled discharge, which can destroy the mask.

According to another embodiment, the coating is also deposited on the back side of the substrate in such a way that it can be contacted with an electrically conductive coating. The front face of the mask blank can also be contacted at the part of the handling area where the coating, in particular its first layer, can be exposed. This represents another important advantage that can be achieved in accordance with the invention, since the mask blank according to the invention can be reliably grounded from the front part, from the side wall or from the back part. In particular, the same device can also be used for grounding purposes, as is used for the handling of the mask blank.

In order to deposit an electrically conductive coating on the back side of the mask substrate, the back side may be supported by a mechanical clamp proximate from the front side or the side portion of the mask substrate. Once the electrically conductive layer is applied to the backside of the mask substrate, the backside portion can be reliably supported during subsequent processing steps by an associated electrostatic chuck from the backside of the mask substrate. As such, sidewalls of the mask substrate may be exposed, thus inducing deposition of an electrically conductive layer on the sidewalls.

According to yet another embodiment, a buffer or stress recovery layer may also be formed in the first layer deposited on the front side, and the buffer or stress recovery layer may form a second layer of the front side coating. . According to one embodiment, the buffer layer or the stress recovery layer may also be deposited in the handling area. However, according to another embodiment, for example, by appropriately masking the front part during deposition, the buffer layer or the stress recovery layer can be prevented from being deposited in the handling region. In this way, during the mechanical manipulation of the mask blank from the front part, it is possible to ensure whether a mechanical clamp or a handling tool is supported in the multi-layer or in the buffer layer or the stress recovery layer in the handling area. .

According to another embodiment, an absorbent layer may be deposited on the buffer layer or the stress recovery layer, which may be composed of, for example, chromium (Cr), TaN or doped TaN. To deposit the absorbing layer, the mask substrate can be supported by an electrostatic chuck or mechanical clamp. According to one embodiment, the front portion is masked during deposition, so that the absorbent layer is not formed in the handling region. According to another embodiment, the front portion of the mask substrate is not masked and the handling region is subsequently exposed again in such a way that the multilayer or the buffer or stress recovery layer is exposed in the handling region, for example by wet etching. do.

According to another embodiment, a stress recovery layer is first applied prior to the deposition of an electrically conductive layer on the back side of the substrate to recover the stress of the back side coating.

According to yet another embodiment, for this purpose the stress recovery layer comprises tantalum nitride, and in particular by which it will be essentially completely constructed. In particular, the chemical composition is given by: tantalum between 45 atomic percent and 62 atomic percent, preferably tantalum between 47 atomic percent and 62 atomic percent; And nitrogen content between 35 atomic percent and 55 atomic percent, preferably between 38 atomic percent and 50 atomic percent.

The layer thickness of this layer is in the range between 172 nm and 178 nm, preferably 175 nm. The actual electrically conductive coating is applied to this stress recovery layer.

According to another embodiment, in particular, the electrically conductive layer has the composition: chromium content between 88 atomic% and 90 atomic%, preferably between 88.5 atomic% and 89.5 atomic%; Nitrogen content between 9 atomic% and 11.5 atomic%, preferably between 9.5 atomic% and 11 atomic%; A carbon content between 0.7 atomic percent and 0.9 atomic percent, preferably 0.8 atomic percent. The layer thickness of this electrically conductive layer is in the range between 58 nm and 62 nm, with 60 nm being preferred. In principle, however, some other metals are suitable according to the invention in order to form the electrically conductive layer.

In order to selectively deposit one, many, or all of the layers already mentioned above, an ion-beam-assisted deposition method (Ion Beam Deposition (IBD)), in particular ion-beam-assisted, in accordance with the invention Sputtering methods can be used. In this way, especially homogeneous and relatively flawless layers can be formed with low residual roughness.

Therefore, according to the invention, the device for handling the mask blank can be used selectively at the same time to ground with the mask blank according to the invention, ie from the front part, the side wall or the rear part of the mask blank.

The invention is described below with reference to the embodiments and the accompanying drawings, in which further features, advantageous configurations and objects to be achieved are derived from them.

Like reference numerals in the drawings indicate components or groups of components that operate in the same or essentially the same manner.

Said mask blank, by the reference numeral (1) shown in full, as shown in Figure 1, the conventional LTE material (Low Thermal Expansion material), for example, body wrapped around (Zerodur ^®), a substrate formed by the Applicant (2 ). The substrate 2 comprises a rear part 3 and a front part 4. As shown in Fig. 1, an electrically conductive coating 5 is deposited on the back side 3, which essentially applies the back side 3 completely. In more detail with regard to the backside coating and forming method, the backside is known from the relevant patent application DE 103 17 792 "Mask Blanks for EUV Lithography and Methods for Making It", filed Apr. 16, 2003 And its corresponding U.S. patent application number no. No. 10 / 825,618, filed April 16, 2004 by Applicant, the content of which is expressly incorporated by reference in the content of this patent application. As described herein, the electrically conductive backside coating is applied by ion-beam-assisted deposition (IBD), in particular by ion-beam-assisted sputtering, which is characterized by very high wear resistance. In particular, the resistance of electrically conductive coatings to rub against fibers according to DIN 58196-5 (DIN = German Industrial Standard) falls at least to category 2, and the resistance of electrically conductive coatings to rub against erasers according to DIN 58196-4. The resistance drops to at least category 2, and when tested with adhesive tape according to DIN 58196-2, the adhesive strength of the electrically conductive coating essentially corresponds to 0% separation. Also here the resistivity of the electrically conductive coating at a layer thickness of approximately 100 nm is at least approximately 10 ⁻⁷ Ωcm, in particular at least approximately 10 ⁻⁶ Ωcm, and even more preferably at least approximately 10 ⁻⁵ Ωcm Is initiated. In this way a mask blank coated on the back side can be supported or adjusted by an electrostatic chuck on the back side without the risk of mechanical wear or particles caused by handling.

As shown in Fig. 1, a multilayer 6, in particular a Si / Mo multilayer, is formed on the front part 4, where the multilayer is known above to reflect radiation, in particular EUV radiation. It can be designed or used in a manner. As shown in FIG. 1, the multilayer 6 also covers the sidewalls of the substrate 2 in the region 7. On the backside, as schematically shown in FIG. 1, the multilayer 6 is in contact with the electrically conductive backside coating 5. This contact 8 is of course formed at the lower edge of the sidewall coating 7 and is somewhat coplanar with each side of the substrate 2. According to another embodiment (not shown), the electrically conductive backside coating 5 may also slightly cover the lower longitudinal longitudinal edge of the substrate 2, so that the electrically conductive backside coating 5 and the The contact between the multilayers 6 may also be formed in the side wall region of the substrate 2. As shown in FIG. 1, the electrically conductive coating 5 does not completely cover the rear portion 3 of the substrate 2, but rather the edge region of the substrate 2 is at least a few regions of the electrical. Not covered by the conductive coating 5, which will be described in more detail below.

As shown in Fig. 1, another layer is applied to the multilayer 6, i.e. a buffer layer or stress recovery layer made of, for example, SiO ₂ , Si, Ru or Ta ₂ O ₅ . compensation layer 9, for example an absorber layer 10 consisting of doped TaN, which is doped with Cr, TaN or in particular Bor, C, or Ge. The absorbing layer 10 and the buffer layer 9 may be photolithographically structured or patterned in a known manner to form a mask region 20 (see FIG. 3) in the central region of the mask blank 1. Can be. As shown in Figs. 1 and 3, according to the present invention, the buffer layer 9 and / or the absorbing layer 10 are not provided in the corner region on the front portion of the mask blank 1. Therefore, in this area the multilayer 6 is exposed as in the first embodiment. According to the first embodiment above, this exposed multilayer area is used to form a handling area on the front part of the mask blank 1, and when handling the mask blank from the front part, a mechanical clamp or A handling device can be supported directly on the handling area. According to the invention, this exposed surface area of the multilayer 6 is sufficiently abrasion resistant and susceptible to stress, so that adjustment from the front part is allowed in the handling area 22 as a result.

According to the first embodiment, the uppermost layer of the multilayer 6 has a certain minimum electrical conductivity such that when the substrate is adjusted from the front part, the mask blank 1 is contacted by contact in the handling area. It may be earthed (cf. Fig. 3). Thus, earthing current passes through the multilayer 6, in particular its top layer, from the handling region 22 (see FIG. 3) through the side wall region 7 and the contact 8. Passed through the electrically conductive backside coating 5, from which they can flow via the electrostatic chuck (not shown). Even in the case of uncontrolled discharge, the mask can still be safely held by the electrostatic chuck since it can be maintained at a defined potential. Grounding is also necessary, for example, in order to prevent unwanted discharge during irradiation of the photoresist layer, especially during writing with the electron beam. As a result, since the mask blank 1 can always be maintained at a defined potential, it can be reliably held by an electrostatic chuck.

The uppermost layer of the multilayer 6 is a silicon layer. Since it is applied to a sufficient thickness, for example at least 11 nm thick, only about 3 nm of the silicon layer best can be oxidized, while the remainder is left unoxidized and is therefore sufficiently electrically conductive. Alternatively, the topmost layer of the multilayer 6 may also be formed of, for example, Ru, Ta ₂ O ₂ and similar other suitable wear resistant materials.

Figure 2 shows a schematic cross sectional view of a mask blank in accordance with a second embodiment of the present invention. Unlike FIG. 1, the buffer layer or stress compensation layer is also formed on the side edge region 7 of the mask blank 1 and extends to the back contact 8. Alternatively, only the side wall area 7 is covered in at least some areas by the buffer or stress recovery layer 9. SiO ₂ The layer is partially suitable as the buffer or tension recovery layer 9. However, as will be apparent to those skilled in the art, any other materials may be used. According to the second embodiment, also the contact in the handling area 22 (see FIG. 3) is in principle pressed by the buffer layer 9 so that a ground rod or the like is in contact with the underlying electrically conductive layer. Induced to lose. This occurs in particular on the side wall of the mask blank 1. According to the second embodiment, a mechanical clamp or handling device proximate from the front part of the mask blank 1 can be supported directly on the buffer layer 9 in the handling area.

If, according to the third embodiment shown in FIG. 4, this is disturbed, one or more cutouts 16 will be formed in the buffer layer 9 in the handling area 22, as described in more detail below. As such, the multilayer 6 located below is exposed. According to the third embodiment, as in the first embodiment, the chuck or the handling device can be supported directly on the multilayer 6 in the handling area 22.

In the following, a method for producing a mask blank according to the present invention will be described with reference to FIG. As will be apparent from the description below, the substrate is optionally supported by mechanical clamps or electrostatic chucks.

5, the mask substrate is first supported by a mechanical clamp proximate from the front portion of the mask substrate, in order to deposit an electrically conductive layer on the back portion. For this purpose, it is desirable to use an ion-beam-assisted sputtering method. The mask substrate coated on the backside is then supported by the electrically conductive backside coating and is moved from the backside to an electrostatic chuck supporting the mask substrate. The multilayer is then deposited on the front side. This multilayer covers the entire front side of the substrate. The top layer of the multilayer has a certain minimum electrical conductivity sufficient to ground the front side of the mask substrate. Since the sidewalls of the mask substrate are exposed during the deposition of the multilayer, the particular coating of the sidewall with the multilayer occurs undoubtedly at the top of the multilayer with a constant minimum conductivity. Inevitably there is a conductive coating on the sidewall of the mask substrate.

As shown in Fig. 5, the mask substrate then moves to the mechanical clamp and is supported by the mechanical clamp. The buffer layer and the absorber layer are then deposited on the front side of the mask substrate. During the deposition of the buffer and absorber layers, a mask is used in the vicinity of the formed handling area (see Figure 3), so that the multilayer is no longer coated within the handling area. In this process, the mask blank shown in FIG. 1 may be formed.

Instead of moving the mask substrate to a mechanical clamp to deposit the buffer layer and absorber layer, in principle, the mask substrate is the same electrostatic chuck or different electrostatic chuck from the back side. While maintained by, the buffer layer and absorber layer will be provided to deposit in accordance with the present invention.

In the modification of the method of Fig. 5, in the modification shown in Fig. 6, the buffer layer is deposited on the front portion of the mask substrate while the mask substrate is still supported by the electrostatic chuck. Therefore, the buffer layer is deposited on the sidewall of the mask substrate to form a mask blank according to the second embodiment shown in FIG.

As shown in Fig. 6, the mask substrate is moved with a mechanical clamp, and then the absorbing layer is deposited on the front portion. During the deposition of the absorbent layer, a mask is once again used to prevent deposition of the absorbent layer within the handling area. In this way, it is also possible to form the mask blank as shown in FIG.

Of course, as shown in Fig. 6, the absorbing layer may be deposited on the front side of the mask substrate when the front side is supported by the same electrostatic chuck or a different electrostatic chuck from the back side.

FIG. 7 shows another variant of the method shown in FIG. 6. In this case, no mask is used during the deposition of the absorber layer on the front part, so that the front part of the mask substrate is completely covered by the absorber layer. In only subsequent processing steps, the buffer layer or stress recovery layer below the absorbing layer or the multilayer layer below the buffer layer is exposed in a predetermined handling area, for example by wet etching. Finally, the mask blank shown in FIG. 2 or 4 can be obtained. Of course, with the method shown in Fig. 7, it is also possible that the absorber layer is deposited on the front side of the mask substrate when the front side is supported by the same electrostatic chuck or a different electrostatic chuck from the rear side.

As it becomes very apparent to those skilled in the art upon studying the above description, in order to recover the stress of the electrically conductive layer as mentioned above, a stress recovery layer comprising tantalum nitride is applied to the backside of the substrate. Before it is possible, it is possible to apply first. A second layer of chromium, nitrogen, and carbon may be applied to this stress recovery layer, as mentioned above.

In studying the above detailed description, as it becomes very apparent to those skilled in the art, other modifications and variations are possible without departing from the general solution, as described above or beyond the scope of the appended claims. In particular, any material other than the above-mentioned materials can be used to form a mask blank for photolithography, in particular EUV photolithography. In addition, a stress recovery layer may alternatively or additionally be provided below the multilayer. Therefore, such other modifications and changes are also intended to be expressly included in the scope of the appended claims.

When producing a mask blank for photolithography according to the present invention, a mask blank is produced which is adjustable in a simpler and more reliable manner. Also provided are methods that are cost effective, can maintain and control reduced wear and can reduce particle formation. Such mask blanks may be encountered in a much simpler and more reliable manner, in particular when adjusting and processing the mask blanks.

Claims (31)

Method for producing a mask blank (1) for photolithography, in particular for EUV lithography, the following steps: Providing a substrate (2) comprising a front portion (4) and a back portion (3); Depositing an electrically conductive layer (5) on the back side of the substrate; Depositing a coating on the front side of the substrate, the coating comprising at least a first layer (6) and a second layer (9); And Structuring the coating for photolithography (6,9); here Each handling region 22 (22a-22c) is formed on the front portion 4 in at least one predetermined position, the handling region being structured for the photolithography by a mechanical clamp or handling device. But is designed for the handling of the mask blank 1, where The first layer 6 is exposed in the respective handling regions 22; 22a-22c so that when the mask blank 1 is adjusted from the front part, the mechanical clamp or the handling device is adapted to the first layer ( 6) a method for manufacturing a mask blank for photolithography. The method of claim 1, The coatings 6, 9 are deposited in such a way that the sidewalls of the substrate 2 are covered in at least several areas, wherein the coatings 6, 9 are electrically conductive. Manufacturing method. The method of claim 2, And the coating (6,9) is deposited on the back side of the substrate in contact with the electrically conductive coating (5). The method according to any one of claims 1 to 3, The substrate 2 is supported by a mechanical clamp or handling device for depositing the electrically conductive layer 5, and the substrate is electrostatic chuck before depositing the first layer 6 on the front side. moving to an electrostatic chuck, wherein said first layer (6) is deposited on said front side while said substrate is supported by an electrostatic chuck. The method of claim 4, wherein Method for producing a mask blank for photolithography, characterized in that the surface of the coating (6,9) is formed of Si or SiO ₂ . The method of claim 5, wherein The first layer is formed of a Si / Mo multilayer (6), characterized in that the mask blank manufacturing method for photolithography. The method according to any one of claims 4 to 6, A method for producing a mask blank for photolithography, wherein a stress recovery layer (9) is formed on the first layer (6), and the stress recovery layer forms the second layer. The method of claim 7, wherein The stress recovery layer is a mask blank manufacturing method for photolithography, characterized in that formed of Cr or SiO ₂ . The method according to claim 7 or 8, The stress recovery layer (9) is a mask blank manufacturing method for photolithography, characterized in that formed in such a way that the side wall of the substrate (2) is enclosed.  The method according to any one of claims 4 to 9, A method for producing a mask blank for photolithography, characterized in that an absorbing layer (10) is deposited on the front portion of the mask blank (1) to weaken or absorb the radiation used for the photolithography. The method according to any one of claims 4 to 10, The substrate 2 is moved to a mechanical clamp or handling device prior to depositing the stress recovery layer 9 and the absorbent layer 10, the mechanical clamp or handling device being moved from the back side 3 to the substrate 2. Wherein at least one region on the front portion 4 of the substrate 2 is masked such that the stress recovery layer 9 and the absorbent layer 10 are each at least in a predetermined handling region 22. A method for manufacturing a mask blank for photolithography, characterized by exposing the first layer (6) formed with one opening and positioned below it. The method according to any one of claims 4 to 10, The substrate 2 is moved to a mechanical clamp or handling device prior to the deposition of the absorbent layer 10, the mechanical clamp or handling device supporting the substrate 2 from the back side 3, where the substrate ( At least one region on the front portion 4 of 2) is masked so that the absorbent layers 10 are each formed with at least one opening in a predetermined handling region 22 and located below the first layer 6. ) Is a mask blank manufacturing method for photolithography, characterized in that exposed. The method according to any one of claims 10 to 12, The absorbing layer (10) is a mask blank manufacturing method for photolithography, characterized in that formed of Cr, TaN, or doped TaN. The method according to any one of claims 10 to 13, The absorbing layer (10) is a mask blank manufacturing method for photolithography, characterized in that formed by the ion beam support sputter. The method according to any one of the preceding claims, A method for producing a mask blank for photolithography, characterized in that the stress recovery layer is first applied to the rear portion (3) of the substrate before the deposition of the electrically conductive layer (5). The method of claim 15, The stress recovery layer has the following composition: Tantalum between 45 atomic percent and 65 atomic percent, preferably tantalum content between 47 atomic percent and 62 atomic percent; And Has a nitrogen content between 35 atomic percent and 55 atomic percent, preferably between 38 atomic percent and 50 atomic percent; Wherein the thickness of the stress recovery layer is between 172 nm and 178 nm and preferably 175 nm. The method according to any one of the preceding claims, The electrically conductive layer 5 has the following composition: Chromium between 88 atomic% and 90 atomic%, preferably between chromium t between 88.5 atomic% and 89.5 atomic%; And Nitrogen content between 9 atomic% and 11.5 atomic%, preferably between 9.5 atomic% and 11 atomic%, and It has a carbon, preferably 0.8 atomic% carbon content between 0.7 atomic% and 0.9 atomic%; Wherein the layer thickness of the electrically conductive layer (5) is in a range between 58 nm and 62 nm, preferably 60 nm. As mask blanks for photolithography, in particular for EUV lithography, A substrate 2 comprising a front portion 4 and a back portion 3; An electrically conductive layer (5) deposited on the back side of the substrate such that the mask blank (1) can be held by an electrostatic chuck; And A coating 6, 9 deposited on the front side of the substrate 2, wherein Each of the handling regions 22; 22a-22c is provided on the front portion in at least one predetermined position, and the handling regions are not structured or provided for the photolithography, but by mechanical clamps or handling devices. In the mask blank for photolithography, which is designed for the handling of the mask blank (1), The coating comprises at least a first layer 6 and a second layer 9, wherein the first layer 6 is exposed in the handling regions 22; 22a-22c, respectively, so that the mask blank 1 The mask blank, characterized in that the mechanical clamp or handling device is supported on the first layer (6) when is adjusted from the front part. The method of claim 18, The coating (6,9) covers the sidewalls of the substrate (2) in at least several areas, wherein the coating (6,9) is electrically conductive. The method of claim 19, The mask blank, characterized in that the coating (6,9) is in contact with an electrically conductive coating (5) on the back side of the substrate. The method of claim 20, Mask blank, characterized in that the surface of the coating (6,9) is formed of Si or SiO ₂ . The method of claim 21, Mask blank, characterized in that the coating comprises a Si / Mo multilayer (6). The method according to any one of claims 20 to 22. Mask blank, characterized in that the coating comprises a stress recovery layer (9). The method of claim 23, The mask blank, characterized in that the stress recovery layer comprises Cr or SiO ₂ . The method of claim 23 or 24, The mask blank, characterized in that the stress recovery layer (9) surrounds the side wall of the substrate. The method according to any one of claims 23 to 25, The mask blank, characterized in that the stress recovery layer (9) each comprises at least one opening formed in a predetermined handling area (22) to expose the first layer (6) located below it. The method according to any one of claims 19 to 26, Mask blank, characterized in that an absorbing layer (10) is deposited on the front side to weaken or absorb the radiation used for the photolithography. The method of claim 27, The absorber layer is mask blank, characterized in that formed of Cr, TaN, or doped TaN. The method according to any one of claims 18 to 28, Mask blank, characterized in that a stress recovery layer is provided between the electrically conductive layer (5) and the back side of the substrate. The method of claim 29, The stress recovery layer has the following composition: Tantalum content between 45 atomic% and 65 atomic%, preferably tantalum content between 47 atomic% and 62 atomic%; And Nitrogen content between 35 atomic percent and 55 atomic percent, preferably between 38 atomic percent and 50 atomic percent; Wherein the thickness of the stress recovery layer is in a range between 172 nm and 178 nm and preferably 175 nm. The method according to any one of claims 18 to 30, The electrically conductive layer 5 has the following composition: Chromium content between 88 atomic% and 90 atomic%, preferably chromium content between 88.5 atomic% and 89.5 atomic%; Nitrogen content between 9 atomic percent and 11.5 atomic percent, preferably between 9.5 atomic percent and 11 atomic percent; And A carbon content between 0.7 atomic percent and 0.9 atomic percent, preferably 0.8 atomic percent; Wherein the layer thickness of the electrically conductive layer (5) is in the range between 58 nm and 62 nm, preferably 60 nm.

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