TWI446405B - Ultraviolet (EUV) mask base - Google Patents

Description

Ultra-violet (EUV) reticle base

The present invention relates to an EUV (Extreme Ultraviolet) lithography reflective reticle substrate (hereinafter referred to as "EUV reticle substrate" in the present specification) used in the manufacture of a semiconductor or the like, and the manufacture of the reticle A substrate used in the case of a substrate (hereinafter referred to as a "substrate for a photomask substrate" in the present specification) or a substrate having a functional film such as a reflective film or a protective layer formed on the substrate.

Further, the present invention relates to a defect inspection method and a defect correction method using the EUV mask substrate, the substrate for a mask substrate, or the substrate having the functional film of the present invention.

Further, the present invention relates to a method of manufacturing an EUV reticle using the EUV reticle substrate of the present invention.

With the high integration of semiconductor elements, the maximum size of defects that are allowed for the lithography mask base and the reticle substrate is becoming smaller and smaller. Specifically, in the lithography technique for fabricating a semiconductor element having a half pitch of 32 nm or less, EUV lithography using light having a wavelength of about 13.5 nm has been studied, but a reticle substrate for EUV lithography is used (hereinafter referred to as In the case of the "EUV mask base" and the substrate for a reticle base, it is required that there is no unevenness in the size of about 30 nm or more in terms of equivalent spherical diameter.

However, it is extremely difficult to realize an EUV reticle substrate and an EUV reticle substrate which are completely free from the disadvantage of having a very small spherical diameter of 30 nm. Substrate. Therefore, various methods for correcting the disadvantages of the EUV mask substrate and the substrate for the mask substrate have been proposed. For example, in order to remove the fine particles present on the substrate for the reticle base, a method of locally heating the substrate by locally irradiating the laser light and removing the fine particles by the difference in thermal expansion between the substrates/particles has been proposed ( Refer to, for example, Patent Document 1). Further, in the EUV mask substrate, in order to eliminate the step (phase defect) caused by the particles buried in the reflective multilayer film, the electron beam or the like is locally irradiated to eliminate the step difference caused by the volume shrinkage by forming the telluride. The method has been studied (refer to, for example, Patent Document 2).

In order to use these methods to correct the shortcomings, it is necessary to correctly grasp the position of the defects. However, the current EUV reticle substrate and the reticle substrate are generally positioned in various process devices (patterning devices, defect correction devices, etc.) or evaluation devices (defect inspection machines, etc.) based on the substrate shape, but positioned. The accuracy is low, and it is about 50 to 100 μm, and it is difficult to accurately determine the position where the equivalent spherical diameter is a very small disadvantage of 30 nm. In addition, since the positioning accuracy is low, it takes a long time to determine the position of the defect.

(Patent Document 1) Japanese Patent Laid-Open Publication No. 2000-61414 (Patent Document 2) Japanese Patent Laid-Open No. 2006-59835

In order to solve the above problems of the prior art, the object is to provide a position which can correctly determine a minor defect of about 30 nm in terms of equivalent spherical diameter. An EUV mask substrate, a substrate for a mask substrate, and a substrate having a functional film.

Further, an object of the present invention is to provide a defect inspection method, a defect correction method, and a method of manufacturing an EUV mask using the EUV mask substrate, the mask substrate, or the substrate having the functional film

In order to achieve the above object, the present invention provides a substrate for a reflective reticle base for ultra-violet (EUV) lithography (hereinafter referred to as "the substrate for a reticle substrate of the present invention"), which is characterized in that a film formation surface of the substrate is provided. At least three marks satisfying the following (1) and (2) are formed: (1) the mark size is 30 to 100 nm in terms of equivalent spherical diameter; and (2) on the film formation surface, the three marks are not in the same imaginary line.

Further, the present invention provides a substrate having a reflective layer for ultra-ultraviolet (EUV) lithography (hereinafter referred to as "the substrate having a reflective layer of the present invention"), which is formed on a substrate to reflect a reflection of ultra-ultraviolet light. a substrate having a reflective layer for ultra-ultraviolet (EUV) lithography, characterized in that at least three marks satisfying the following (1) and (2) are formed on the surface of the reflective layer: (1) the mark size is equivalent to the ball The diameter is 30 to 100 nm; (2) on the surface of the reflective layer, the three marks are not in the same imaginary line.

Provided is a substrate having a reflective layer for ultra-violet (EUV) lithography (hereinafter referred to as "the substrate having a reflective layer and a protective layer of the present invention"), which is sequentially formed on a substrate to reflect the reflection of ultra-ultraviolet light. a layer; and an ultra-violet (EUV) lithography for protecting the protective layer of the reflective layer a substrate using a reflective layer, characterized in that at least three marks satisfying the following (1) and (2) are formed on the surface of the protective layer: (1) the mark size is 30 to 100 nm in terms of equivalent spherical diameter; (2) On the surface of the protective layer, the three marks are not in the same imaginary line.

Hereinafter, in the present specification, the substrate for a photomask substrate of the present invention, the substrate having a reflective layer of the present invention, and the reflective layer of the present invention are sometimes used. The substrate of the protective layer is collectively referred to as the substrate for EUV mask substrate of the present invention (generalized).

In addition, the present invention provides a reflective reticle substrate (A) for ultra-ultraviolet (EUV) lithography, which is formed on a substrate to sequentially form a reflective layer for reflecting ultra-ultraviolet light; and for absorbing absorption of ultra-ultraviolet light. A super-ultraviolet (EUV) lithography reflective layer substrate for a bulk layer, characterized in that at least three marks satisfying the following (1) and (2) are formed on the surface of the absorber layer: (1) the mark size is equivalent to the sphere The diameter is 30 to 100 nm; (2) on the surface of the absorber layer, the three marks are not in the same imaginary line.

In addition, the present invention provides a reflective reticle substrate (B) for ultra-ultraviolet (EUV) lithography, which is formed on a substrate to sequentially form a reflective layer for reflecting ultra-ultraviolet light; and an absorber layer for absorbing ultra-ultraviolet light. And a reflective reticle substrate for ultra-ultraviolet (EUV) lithography for detecting a low-reflection layer having low reflection light when used for inspection of a mask pattern, characterized in that the surface of the low-reflection layer is formed to satisfy the following (1) At least 3 marks of (2): (1) The mark size is 30 to 100 nm in terms of equivalent spherical diameter; (2) On the surface of the low reflection layer, the three marks are not in the same imaginary line.

Hereinafter, in the present specification, the above-described EUV lithography reflective reticle substrates (A) and (B) are collectively referred to as the EUV reticle substrate of the present invention.

In the EUV reticle substrate of the present invention, it is preferable that a protective layer for protecting the absorber layer is formed between the reflective layer and the absorber layer.

The EUV reticle substrate of the present invention, the substrate for the reticle substrate, the substrate having the reflective layer, and the reflective layer. In the substrate of the protective layer, it is preferable that the marking is formed outside the exposed area during patterning.

Further, in the substrate for a reticle base of the present invention, it is preferable that the mark is formed in a range of from 108 × 132 mm □ to 149 × 149 mm □ of the film formation surface.

Further, in the substrate having the reflective layer of the present invention, it is preferable that the mark is formed in a range of from 108 × 132 mm □ to 149 × 149 mm □ of the surface of the reflective layer.

Furthermore, in the invention there is a reflective layer. In the substrate of the protective layer, it is preferable that the mark is formed in the range of 108 × 132 mm □ to 149 × 149 mm □ of the surface of the protective layer.

Further, in the EUV reticle base (A) of the present invention, it is preferable that the mark is formed in a range of from 108 × 132 mm □ to 149 × 149 mm □ on the surface of the absorber layer.

Further, in the EUV reticle base (B) of the present invention, it is preferable that the foregoing The marking is formed in the range of 108 × 132 mm □ to 149 × 149 mm □ of the surface of the aforementioned low reflection layer.

The EUV reticle substrate of the present invention, the substrate for the reticle substrate, the substrate having the reflective layer, and the reflective layer. In the substrate of the protective layer, it is preferable that the distance between the marks is 150 nm or more apart.

Further, in the substrate for a reticle base of the present invention, it is preferable that an auxiliary mark for identifying the mark is formed on the film formation surface of the substrate.

Further, in the substrate having the reflective layer of the present invention, it is preferable to additionally form an auxiliary mark for identifying the aforementioned mark on the surface of the aforementioned reflective layer.

Furthermore, in the invention there is a reflective layer. Preferably, in the substrate of the protective layer, an auxiliary mark for identifying the aforementioned mark is additionally formed on the surface of the protective layer.

Further, in the EUV reticle base (A) of the present invention, it is preferable to additionally form an auxiliary mark for identifying the aforementioned mark on the surface of the aforementioned absorber layer.

Further, in the EUV reticle base (B) of the present invention, it is preferable to additionally form an auxiliary mark for identifying the aforementioned mark on the surface of the aforementioned low reflection layer.

Further, the present invention provides a method for inspecting a defect of a substrate for a mask base of the present invention comprising the step of determining a position of a defect using a mark formed on the film formation surface.

Further, the present invention provides a substrate for a reticle substrate of the present invention comprising: a step of determining a position of a defect using a mark formed on the film formation surface; and a step of correcting a defect in which the position is determined in the step The shortcomings of the correction method.

Further, the present invention provides a method for inspecting a defect of a substrate having a reflective layer of the present invention comprising the step of determining a position of a defect using a mark formed on a surface of the reflective layer.

Further, the present invention provides a substrate comprising a reflective layer of the present invention comprising the steps of determining a position of a defect using a mark formed on a surface of the reflective layer; and a step of correcting a defect in which the position is determined in the step. The shortcomings of the correction method.

In addition, the present invention provides a reflective layer comprising the present invention comprising the step of determining the position of the defect using a mark formed on the surface of the protective layer. The defect inspection method of the substrate of the protective layer.

Further, the present invention provides a method comprising: a step of determining a position of a defect using a mark formed on a surface of the protective layer; and a reflective layer of the present invention for correcting a step of determining a position in the step. A method for correcting the defects of the substrate of the protective layer.

Further, the present invention provides a method for inspecting the defect of the EUV reticle substrate of the present invention comprising the step of determining the position of the defect using the mark formed on the surface of the absorbent body layer.

Further, the present invention provides a step of: determining a position of a defect using a mark formed on a surface of the absorber layer; and fine-tuning a pattern on the mask substrate according to a position determined by the defect in the step The step of locating the method (C) for producing a reflective reticle for EUV lithography using the EUV reticle substrate of the present invention.

Further, the present invention provides a method comprising: using the formation of the aforementioned low anti A defect inspection method of the EUV reticle substrate of the present invention for marking the surface of the layer to determine the location of the defect.

Further, the present invention provides a step of: determining a position of a defect using a mark formed on a surface of the aforementioned low-reflection layer; and fine-tuning patterning on the reticle base according to a position of a defect determined in the step The step of position is to use the EUV reticle substrate of the present invention to manufacture a reflective reticle for EUV lithography (D).

Hereinafter, in the present specification, the methods (C) and (D) for producing the reflective mask for EUV lithography are referred to as the method of manufacturing the EUV mask of the present invention.

According to the present invention, when the EUV mask base or the EUV mask base substrate (generalized) is inspected, the position of a minor defect of about 30 nm in terms of equivalent spherical diameter can be correctly determined.

Further, according to the present invention, when the defect of the EUV mask base or the EUV mask base substrate (generalized) is corrected, the correction is determined because the position of the minor defect of about 30 nm in terms of the equivalent spherical diameter is correctly determined. The disadvantage of the position is that an EUV mask base or an EUV mask base substrate (generalized) which does not have the disadvantage of causing adverse effects when performing EUV lithography can be obtained.

Further, according to the present invention, since the position of the minor defect of about 30 nm in terms of the equivalent spherical diameter is correctly determined, and the position where the EUV mask base is patterned is finely adjusted according to the position of the determined defect, It is possible to obtain an EUV mask which does not cause a defect at a position which affects the pattern, or which minimizes the influence on the pattern accuracy.

The invention will be described below with reference to the drawings.

<Substrate for reticle base>

Fig. 1 is a plan view showing an example of a substrate for a mask base of the present invention. In Fig. 1, the film formation surface of the substrate 1 is shown, that is, the surface of the substrate on which the multilayer reflection film and the absorber layer are formed in the manufacturing process of the EUV mask substrate. However, in order to make it easy to understand, each component in FIG. 1 may be displayed in a size different from the actual size.

In the substrate 1 for a reticle base of the present invention, in order to accurately determine the position of the defects (3a, 3b, 3c) existing on the film formation surface of the substrate 1, the film formation surface is formed to satisfy the following (1). And (2) at least three marks (2a, 2b, 2c): (1) the mark size is 30 to 100 nm in terms of equivalent spherical diameter; (2) on the film formation surface, the three marks are not in the same imaginary line.

In the present invention, the mark (2a, 2b, 2c) is formed on the film formation surface of the substrate 1 for the mask base in order to inspect the film formation surface using the defect inspection machine, and the mark (2a, 2b, 2c). In terms of the relative position, more specifically, the relative position of the axis (20, 21) between the joint marks (2a, 2b, 2c) is used to determine the defect in the film formation surface of the substrate 1 (3a) , 3b , 3c) position.

Therefore, the mark (2a, 2b, 2c) is required to be detected by the defect checker. Therefore, the marks (2a, 2b, 2c) formed on the film formation surface of the substrate 1 for the mask base have a portion that is deformed into a concave shape or a convex shape with respect to the film formation surface.

In the present invention, the equivalent spherical diameter SEVD (nm) used as an index of the mark size is calculated by the following formula based on the volume of the portion deformed into a concave shape or a convex shape by the above-mentioned film formation surface.

SEVD=2(3V/4π) ^1/3

Here, as shown in FIG. 2, when the maximum depth of the concave portion measured by the film formation surface is h, V is a volume (nm ³ ) of the concave portion from the film formation surface to a depth corresponding to 0.9 h. When the mark has a portion that is deformed into a convex shape with respect to the film formation surface, the volume of the convex portion from the film formation surface to a height corresponding to 0.9 h (h is the maximum height of the convex portion measured by the film formation surface) . Among them, the V system can be measured by atomic force microscopy (AFM).

If the size of the mark (2a, 2b, 2c) is 30 nm or more in terms of the equivalent spherical diameter, it can be sufficiently detected by the defect inspection machine.

On the other hand, when the size of the mark (2a, 2b, 2c) exceeds 100 nm by the equivalent spherical diameter, the detection position accuracy of the mark obtained by the defect inspection machine is low. For example, when the film formation surface is inspected by the defect inspection machine, a deviation occurs at the position of the detected mark, and the detection position reproducibility of the mark is low. As a result, as the axis (20, 21) between the joint marks (2a, 2b, 2c) The positional accuracy (3a, 3b, 3c) determined by the relative position is less accurate. That is, when the mark is too large, it is difficult to correctly detect the position of the mark, and it is not clear as the position of the defect determined by the relative position of the mark.

As described in Japanese Laid-Open Patent Publication No. 2007-33857, an identification code for manufacturing management or the like, or a mark including substrate inspection material information or the like is provided on the substrate for a mask base, which has been conventionally performed. However, based on the fact that it is usually necessary to perform scanning by a scanning electron microscope (SEM) or an optical microscope, and it is necessary to include information such as an identification code, substrate inspection data, and the like, the marks provided for these purposes are relatively large, and are micrometer-scale. size. For example, JP-A-2007-33857 discloses that a concave portion having an opening width of 100 to 500 μm and a depth of 3 to 20 μm is formed as a mark on the substrate. When the substrate having the mark of the size shown above is inspected by the defect detecting machine, the detection position accuracy of the mark is extremely low. For example, a considerable deviation occurs at the position of the detected mark, the detection position of the mark is extremely reproducible, and the offset of the mark detection position becomes more than +/- 500 nm.

Even if the position where the defect is determined as the relative position of the mark having the lower detection position accuracy as described above, the positional accuracy of the determined defect is extremely low, which is not sufficient when used for the defect correction or the like.

If the mark size is 30 to 100 nm in terms of equivalent spherical diameter, it can be detected by the defect inspection machine, and the detection position of the mark is excellent in accuracy. For example, the detection position of the mark is reproducible, and the offset of the detection position is +/ -150 nm or less. A more preferred mark size is 40 to 80 nm in terms of equivalent spherical diameter.

In this regard, it is intended to include the Japanese Patent Laid-Open No. 2007-33857. A conventional mark such as an identification code or a substrate inspection material information for manufacturing management such as a mark, and a mark formed on a film formation surface of the substrate in the present invention, which is described in the report, is performed by a defect inspection machine. A comparative experiment in which the obtained detection position reproducibility was compared.

Comparative experiment The defect inspection machine is used, and it is not necessary to load/unload a substrate having various sizes of marks on the surface (having a portion which is deformed to be convex with respect to the surface of the substrate), and five consecutive inspections are performed to obtain a mark detection position. The offset.

Table 1 shows the results of the conventional label (pixel 1286, equivalent spherical diameter (SEVD) 2 μm). In Table 1, the results of each inspection are displayed, and the displacement amount of the detected coordinates when performing the second to fifth inspections based on the first inspection result (detection coordinate) is used and the following equation is used. The offset that is produced.

Offset = {(displacement in x direction) ² + (displacement in y direction) ² } ^0.5

In Table 1, the maximum offset is 4555 nm.

Table 2 shows the same results as described above with respect to the mark (pixel 8.4, equivalent spherical diameter (SEVD) 70 nm) of the present invention. In Table 2, the maximum offset is 206 nm.

Similarly to the above, the offset amount of the detection position is obtained for nine pixels of the pixel 1286 (equivalent spherical diameter (SEVD) of about 2 μm) to the pixel of 6.2 (equivalent spherical diameter (SEVD) of 64 nm). The results are shown in Table 3.

Regarding the six marks of the pixel 6.2 (equivalent spherical diameter (SEVD) 64 nm) to the pixel 44 (equivalent spherical diameter (SEVD) 370 nm), the relationship between the maximum offset and the SEVD is shown in FIG. As can be seen from Fig. 3, when the mark having SEVD of 100 nm or less (pixel 10 or less) has a maximum offset of 300 nm (hence, the offset is +/- 150 nm or less), the level is not problematic. On the other hand, in the case of a mark having a SEVD of 200 nm or more (pixels 20 or more), the maximum offset is more than 1 μm (hence the offset exceeds +/- 500 nm).

Further, if the SEVD is a large mark, when the SEVD is a mark of about 4 μm (pixel 204), the maximum offset is 3.6 μm, and when the SEVD is a mark of about 12 μm (pixel 693), the maximum offset is 11μm, the maximum offset is larger.

Wherein, when it is considered that the reproducibility of the detection position when the mark is detected by the defect inspection machine is +/- 150 nm or less, the distance between the respective marks (2a, 2b, 2c) is preferably 150 nm or more apart, 1 cm or more apart Preferably, it is more preferably 5 cm or more apart from each other.

In order to determine the correct position of the defects (3a, 3b, 3c) in the film formation surface of the substrate 1 in terms of the relative positions of the axes (20, 21) between the joint marks (2a, 2b, 2c), at least 2 axis. Therefore, at least three marks (2a, 2b, 2c) must be provided on the film formation surface, and the three marks (2a, 2b, 2c) must be arranged so as not to be on the same imaginary straight line on the film formation surface.

However, the number of marks formed on the film formation surface is not limited to three, and may be four or more. When the number of the marks is four or more, it is sufficient that the three marks among the marks are not on the same imaginary line when arranged on the film formation surface.

The shape (2a, 2b, 2c) is not particularly limited as long as its size is 30 to 100 nm in terms of equivalent spherical diameter, and the planar shape in the film formation surface may be triangular, rectangular, or other polygonal shape. It may be an elliptical shape, a Sichuan shape in which three lines are arranged in parallel, a cross shape in which two lines are intersected, and the like, and a plurality of elements constitute one marker. However, in terms of the accuracy of the detection position of the mark caused by the defect inspection machine, the planar shape in the film formation surface is preferably circular.

Preferably, an auxiliary mark for identifying the mark is formed around the mark for determining the position of the defect. Since the mark used for determining the position of the defect is 30 to 100 nm in terms of the equivalent spherical diameter, it is difficult to confirm the presence or absence of the mark before the inspection by the defect inspection machine, that is, whether the surface to be inspected is formed with the mark. On the side, it is difficult to roughly determine the position where the mark is formed. By forming the auxiliary mark around the mark for determining the position of the defect, it is easier to confirm the presence or absence of the mark, or to roughly determine the position at which the mark is formed, and to shorten the time required for the defect checker to perform the test.

Therefore, the auxiliary marking system must be such that it can be easily recognized by a scanning electron microscope (SEM) or an optical microscope. Here, the sufficient size that can be easily recognized by a scanning electron microscope means that the size is more than 500 nm in terms of equivalent spherical diameter, and the sufficient size that can be easily recognized by an optical microscope means that the spherical diameter is equivalent. It is calculated to be more than 500 nm in size. The size of the auxiliary mark is preferably an equivalent spherical diameter of about 1 to 10 μm, more preferably about 2 to 6 μm.

Further, the auxiliary mark must be formed by separating the marks sufficiently spaced so as not to impair the accuracy of the detection position of the mark caused by the defect inspection machine. The distance between the mark and the auxiliary mark is preferably 10 μm or more, and more preferably 20 μm or more, which does not impair the detection position accuracy of the mark caused by the defect inspection machine.

An example of the arrangement of the mark and the auxiliary mark is shown in FIG. In Fig. 4, four auxiliary marks 4 are formed around the mark 2 having an equivalent spherical diameter of 30 to 100 nm at the position of the defective portion as a whole in a substantially cruciform shape. Here, the length of the auxiliary mark 4 in the longitudinal direction is, for example, 100 μm. Further, the distance between the mark 2 and the auxiliary mark 4 is, for example, 10 μm, preferably 5 μm or more.

The shape and arrangement of the auxiliary marks are not limited to those shown in the drawings, and the marks can be recognized and the preferred shapes and configurations can be appropriately selected. For example, it may be only two auxiliary marks 4 formed on the upper and lower sides of the mark 2 in FIG. 4, or only two auxiliary marks 4 formed on the left and right sides of the mark 2. Further, it is also possible to form the auxiliary marks in the shape of a circle, an ellipse, a triangle, a quadrangle, a hexagon, an octagon or the like in such a manner that the mark is positioned inside thereof.

The marks (2a, 2b, 2c) formed on the film formation surface of the substrate 1 are in the range of 30 to 100 nm in terms of equivalent spherical diameter, and therefore, in the exposure region at the time of patterning, more specifically, in use When the mask base manufactured by the substrate 1 has marks (2a, 2b, 2c) in the exposed region 11 at the time of patterning, there is a disadvantage that the marks (2a, 2b, 2c) themselves are formed as a base of the mask. Therefore, the marks (2a, 2b, 2c) are preferably formed outside the exposed areas at the time of patterning. For example, in the current specification, in the case of a substrate of 152.0 × 152.0 mm □ (vertical 152.0 mm × width 152.0 mm), the exposure area at the time of patterning is 108 × 132 mm □ (the area indicated by the line 11 in Fig. 1). Therefore, it is preferable to form a mark on the outer side of the area. Wherein, the exposed area is usually centered at the center of the substrate.

On the other hand, when the substrate is held or the like, the vicinity of the outer end of the substrate is compared with the other portions of the substrate, and the detection accuracy of the defect inspection machine is lowered. For example, if it is a conventional defect inspection machine that uses a substrate of 152.0 × 152.0 mm □, the quality assurance area is 149 × 149 mm □ (the area shown by the line 12 in Fig. 1), so that it is formed in this area. Mark as good.

Therefore, according to the current specifications of the substrate of 152.0 × 152.0 mm □, when using the existing defect inspection machine to detect the defects, in the area of 108 × 132 mm □ to 149 × 149 mm □ (in the first figure, the line 11 and the line The area between the 12) settings is better.

As described above, the position where the mark is formed on the film formation surface of the substrate is described based on the current specifications of the substrate of 152.0 × 152.0 mm □ and the quality assurance area of the existing defect inspection machine, but the exposure of the substrate size and patterning Relevant specifications of the area, quality assurance area of the defect inspection machine used When the fields and the like are different, they can be appropriately selected depending on the conditions.

The method of forming the marks (2a, 2b, 2c) on the film formation surface of the substrate 1 does not adversely affect the portion where the mark of the substrate is formed, but can be formed on the film formation surface of the substrate 1 by an equivalent spherical diameter of 30. The mark to the size of 100 nm is not particularly limited. For example, the laser beam is irradiated at a desired position on the film formation surface of the substrate 1, and the film formation surface having the substrate 1 is formed by sublimation, melting, or volume contraction of the irradiation portion, or a combination of the two or more. A method of forming a mark in a concave portion, a method of forming a mark by a lithography process, and a method of forming a mark by an indentation caused by a minute pressure.

The substrate 1 is required to satisfy the characteristics of the substrate used as the EUV mask substrate. Therefore, the substrate 1 has a low coefficient of thermal expansion (specifically, a thermal expansion coefficient of 20 ° C is preferably 0 ± 0.05 × 10 ^-7 / ° C, preferably 0 ± 0.03 × 10 ^-7 / ° C), for smoothness. The flatness and the resistance to the cleaning solution used for cleaning the EUV mask base or the patterned EUV mask are preferred. The substrate 1 is specifically a glass having a low coefficient of thermal expansion, for example, SiO ₂ —TiO ₂ -based glass, but is not limited thereto, and a crystallized glass in which a β quartz solid solution is precipitated or Quartz glass or a substrate such as tantalum or metal.

The substrate 1 is preferably formed by a smooth surface having a surface roughness (rms) of 0.15 nm or less and a flatness of 100 nm or less in a patterned EUV mask to obtain high reflectance and transfer accuracy.

The size or thickness of the substrate 1 is appropriately determined depending on the design value of the mask, etc., but the most general shape is 152.0 × 152.0 mm □ and the thickness is 6.35mm.

<Substrate with reflective layer>

In the substrate having a reflective layer of the present invention, a reflective layer for reflecting EUV light is formed on the substrate, and at least three marks satisfying the following (1) and (2) are formed on the surface of the reflective layer: (1) The mark size is 30 to 100 nm in terms of equivalent spherical diameter; (2) on the surface of the reflective layer, the three marks are not in the same imaginary straight line.

Here, the mark formed on the surface of the reflective layer is the same as the mark formed on the film formation surface of the substrate except that the portion where the mark is formed is the surface of the reflective layer, and thus the description thereof is omitted. Among them, it is preferable to form an auxiliary mark for identifying the mark around the mark formed on the surface of the reflective layer.

In addition, the substrate is the same as the above except that no mark is formed on the film formation surface, and thus the description thereof is omitted.

The reflective layer is not particularly limited as long as it has a desired characteristic as a reflective layer of the EUV mask base. Here, a particularly desirable property of the reflective layer is the high EUV light reflectivity. Specifically, when the light of the wavelength region of the EUV light is irradiated onto the surface of the reflective layer, the maximum value of the light reflectance in the vicinity of the wavelength of 13.5 nm is preferably 60% or more, and more preferably 65% or more.

Since the reflective layer can achieve high EUV light reflectance, a multilayer reflective film in which a high refractive index layer and a low refractive index layer are laminated in plural plural times is usually used as a reflective layer. In the multilayer reflective film forming the reflective layer, Mo is widely used in the high refractive index layer, and the low refractive index layer is widely used. Use Si. That is, the Mo/Si multilayer reflective film is the most common. However, the multilayer reflective film is not limited thereto, and a Ru/Si multilayer reflective film, a Mo/Be multilayer reflective film, a Mo compound/Si compound multilayer reflective film, a Si/Mo/Ru multilayer reflective film, and Si/Mo/Ru may be used. /Mo multilayer reflective film, Si/Ru/Mo/Ru multilayer reflective film.

The film thickness of each layer constituting the multilayer reflective film forming the reflective layer and the number of overlapping units of the layer can be appropriately selected in accordance with the EUV light reflectance required for the film material and the reflective layer to be used. Taking a Mo/Si reflective film as an example, in order to form a reflective layer having a maximum EUV light reflectance of 60% or more, the multilayer reflective film is a Mo layer having a film thickness of 2.3 ± 0.1 nm and a film thickness of 4.5 ± 0.1 nm. The Si layer may be laminated in such a manner that the number of reverse units is from 30 to 60.

In addition, each layer which comprises the multilayer reflective film which forms a reflective layer can be formed by the well-known film-forming method, such as a magnetron sputtering method and ion beam- For example, when a Si/Mo multilayer reflective film is formed by ion beam sputtering, a Si target is used as a target, and Ar gas (gas pressure: 1.3 × 10 ^-2 Pa to 2.7 × 10 ^-2 Pa) is used as a sputtering. The gas was formed into a Si film so as to have a thickness of 4.5 nm at an ion acceleration voltage of 300 to 1500 V and a film formation rate of 0.03 to 0.30 nm/sec. Next, using a Mo target as a target, an Ar gas (gas pressure of 1.3 × 10 ^{-) was used. 2} Pa to 2.7 × 10 ^-2 Pa) As the sputtering gas, it is preferable to form the Mo film so as to have a thickness of 2.3 nm with an ion acceleration voltage of 300 to 1500 V and a film formation rate of 0.03 to 0.30 nm/sec. In this case, the Si film and the Mo film were laminated for 40 to 50 cycles, whereby a Si/Mo multilayer reflective film was formed.

In order to prevent oxidation of the surface of the reflective layer, it is preferred that the uppermost layer of the multilayer reflective film forming the reflective layer is formed as a material which is difficult to oxidize. A layer of a material that is difficult to oxidize has a function as a cover layer of a reflective layer. A specific example of the layer which is a material which is hard to oxidize which functions as a cover layer is a Si layer. When the multilayer reflective film forming the reflective layer is a Si/Mo film, the uppermost layer can be formed as a cover layer by forming the uppermost layer as a Si layer. At this time, the film thickness of the coating layer is preferably 11.0 ± 1.0 nm.

<has a reflective layer. Protective substrate > In the invention there is a reflective layer. In the substrate of the protective layer, a reflective layer for reflecting EUV light and a protective layer for protecting the reflective layer are sequentially formed on the substrate. At least three marks satisfying the following (1), (2) are formed on the surface of the protective layer: (1) the mark size is 30 to 100 nm in terms of equivalent spherical diameter; (2) on the surface of the protective layer, 3 marks Not in the same imaginary line.

Here, the mark formed on the surface of the protective layer is the same as the mark formed on the film formation surface of the substrate except that the portion where the mark is formed is the surface of the protective layer, and thus the description thereof is omitted. Among them, an auxiliary mark for identifying the mark is preferably formed around the mark formed on the surface of the protective layer.

In addition, the substrate is the same as the above except that no mark is formed on the film formation surface, and thus the description thereof is omitted.

Further, regarding the reflective layer, except that no mark is formed on the surface of the reflective layer The rest are the same as described above, and the description is omitted.

The protective layer is formed by etching process, usually by patterning on the absorber layer of the EUV mask substrate by a dry etching process, so that the reflective layer is not damaged by the etching process, and the reflective layer is protected. Assume. Therefore, in terms of the material of the protective layer, it is difficult to be affected by the etching process of the absorber layer, that is, the etching rate is slower than that of the absorber layer, and it is difficult to be damaged by the etching process. Examples of the substance satisfying the conditions are, for example, Cr, Al, Ru, Ta, and the like, and SiO ₂ , Si ₃ N ₄ , Al ₂ O ₃ or a mixture thereof. Among these, Ru, CrN, and SiO _{2 are} preferred, and Ru is particularly preferred.

The thickness of the protective layer is preferably from 1 to 60 nm, more preferably from 1 to 20 nm.

The protective layer is formed by a known film formation method such as a magnetron sputtering method or an ion beam sputtering method. When a Ru film is formed by magnetron sputtering, a Ru target is used as a target, and Ar gas (gas pressure: 1.0 × 10 ^-1 Pa to 10 × 10 ^-1 Pa) is used as a sputtering gas to supply electric power. It is preferable to form a film so as to have a thickness of 2 to 5 nm from 30 W to 500 W and a film formation rate of 5 to 50 nm/min.

<EUV reticle base> In the EUV reticle substrate of the present invention, a reflective layer for reflecting EUV light and an absorber layer for absorbing EUV light are sequentially formed on the substrate. The surface of the absorber layer is formed to satisfy the following (1), (2) There are three fewer marks: (1) the mark size is 30 to 100 nm in terms of equivalent spherical diameter; (2) on the surface of the absorber layer, the three marks are not in the same imaginary line.

Here, the mark formed on the surface of the absorber layer is the same as the mark formed on the film formation surface of the substrate except that the portion where the mark is formed is the surface of the absorber layer, and thus the description thereof is omitted. Among them, an auxiliary mark for identifying the mark is preferably formed around the mark formed on the surface of the absorber layer.

In addition, the substrate is the same as the above except that no mark is formed on the film formation surface, and thus the description thereof is omitted. The reflective layer is also the same as the above except that no mark is formed on the surface of the reflective layer, and thus the description thereof is omitted.

In the EUV reticle substrate of the present invention, a protective layer for protecting the reflective layer may be disposed between the reflective layer and the absorber layer. The protective layer is the same as the above except that no mark is formed on the surface, and therefore will be omitted.

A particularly desirable property of the absorber layer is the extremely low EUV light reflectance. Specifically, when the light of the wavelength region of the EUV light is irradiated onto the surface of the absorber layer, the maximum light reflectance at a wavelength of 13.5 nm is preferably 0.5% or less, more preferably 0.1% or less.

The absorber layer is composed of a material having a high absorption coefficient for EUV light, and specifically, a layer containing Cr or Ta, for example, a layer containing a nitride of Cr or Ta, or a layer containing Ta and Hf ( TaHf layer) A layer containing Ta, B, Si, and N (TaBSiN layer).

The absorber layer is not particularly limited as long as the above characteristics are satisfied, but the reflectance of the EUV light of the TaHf layer and the TaBSiN layer is extremely low, and the crystal state of the layer is amorphous, and the surface of the absorber layer is smooth. Good sex, so it is ideal. When the surface roughness of the surface of the absorber layer is large, the edge roughness of the pattern formed on the absorber layer becomes large, and the dimensional accuracy of the pattern deteriorates. As the pattern becomes finer, the effect of the edge roughness becomes more pronounced, so the surface of the absorber layer is required to be smooth.

If the absorber layer is a TaHf layer or a TaBSiN layer, since the film is formed into an amorphous structure or a film of a microcrystalline structure, the surface roughness (rms) of the surface of the absorber layer is 0.5 nm or less, and the surface of the absorber layer is very smooth. Therefore, there is no possibility that the dimensional accuracy of the pattern is deteriorated due to the influence of the edge roughness. The surface roughness (rms) of the surface of the absorber layer is preferably 0.4 nm or less, more preferably 0.3 nm or less.

In the specification, the case where the "crystalline state is amorphous" is not limited to an amorphous structure having no crystal structure at all. Also includes a microcrystalline constructor. When the absorber layer is a film having an amorphous structure or a film having a microcrystalline structure, the surface of the absorber layer is excellent in smoothness.

Here, the crystal state of the absorber layer is amorphous, that is, it is an amorphous structure or a microcrystalline structure can be confirmed by an X-ray diffraction (XRD) method. When the crystal state of the absorber layer is an amorphous structure or a microcrystal structure, no sharp peak is observed in the diffraction peak obtained by XRD measurement.

When the absorber layer is a TaHf layer, it is preferable to use a specific ratio described below. Examples include Ta and Hf.

The Hf content of the absorber layer is 20 to 60 at%, and the crystal state of the absorber layer is easily formed into an amorphous state, and the surface of the absorber is excellent in smoothness, which is preferable. Further, the absorber layer has excellent characteristics such as light reflectance of EUV light and low light reflectance in a wavelength range of pattern inspection light, in the case of an EUV mask base.

The Hf content of the absorber layer is preferably from 30 to 50 at%, more preferably from 30 to 45 at%.

In the absorber layer, it is preferable that Ta is a residue other than Hf. Therefore, the Ta content in the absorber layer is preferably 40 to 80 at%. The Ta content in the absorber layer is preferably from 50 to 70 at%, more preferably from 55 to 70 at%.

In the absorber layer, the composition ratio of Ta to Hf (atomic ratio of Ta:Hf) is preferably from 7:3 to 4:6, more preferably from 6.5:3.5 to 4.5:5.5, and from 6:4 to 5 : 5 is especially good.

The TaHf layer can be formed by performing a sputtering method using a TaHf compound target, for example, magnetron sputtering or ion beam sputtering in an inert gas atmosphere.

Since the TaHf compound target has a composition of Ta = 30 to 70 at% and Hf = 70 to 30 at%, an absorber layer having a desired composition can be obtained, and the composition of the film or the unevenness of the film thickness can be avoided, which is preferable.

When the TaHf layer is formed by the above method, specifically, it may be carried out under the following film forming conditions.

Sputtering gas: Ar gas (gas pressure 1.0 × 10 ^-1 Pa to 50 × 10 ^-1 Pa, preferably 1.0 × 10 ^-1 Pa to 40 × 10 ^-1 Pa, 1.0 × 10 ^-1 Pa to 30 × 10 ^-1 Pa is better)

Input power: 30 to 1000W, preferably 50 to 750W, preferably 80 to 500W

Film formation rate: 2.0 to 60 nm/min, preferably 3.5 to 45 nm/min, more preferably 5 to 30 nm/min

When the absorber layer is a TaBSiN layer, it is preferable to contain Ta, B, Si, and N in a specific ratio as described below.

The B content of the TaBSiN layer is preferably 1 at% or more and less than 5 at%. Conventionally, when a film containing Ta and B (TaB film, TaBN film, TaBO film, TaBNO film) is used as the absorber layer, in order to form the crystal state of the film to be amorphous, it is necessary to form the film B content to 5 at. %the above. However, when the B content of the film is 5 at% or more, the film formation rate is slow, or it is difficult to control the B content rate or the film thickness of the film.

In the present invention, since the TaBSiN layer contains Ta, B, Si, and N at a specific ratio, even if the B content is less than 5 at%, the crystalline state is formed to be amorphous.

When the B content is less than 1 at%, in order to form the crystalline state to be amorphous, it is necessary to increase the amount of addition of Si. Specifically, the Si content is required to be more than 25 at%, and the film thickness required to form the EUV light reflectance to 0.5% or less is increased, which is not preferable. When the B content is 5 at% or more, the above problems such as a slow film formation rate occur.

The B content is preferably from 1 to 4.5 at%, more preferably from 1.5 to 4 at%. If it is 1.5 to 4 at%, in addition to stable film formation, the mask The smoothness of the desired characteristics is also excellent, and it is ideal because it achieves a good balance.

The Si content of the TaBSiN layer is 1 to 25 at%. When the Si content is less than 1 at%, the crystalline state is not formed into an amorphous state. Since the Si-based EUV light has a low absorption coefficient, when the Si content exceeds 25 at%, the film thickness required to form the EUV light reflectance to 0.5% or less is increased, which is not preferable.

The Si content is preferably from 1 to 20 at%, more preferably from 2 to 12 at%.

In the TaBSiN layer, Ta and N are the residues other than B and Si. The composition ratio of Ta to N in the TaBSiN layer (atomic ratio of Ta:N) is 8:1 to 1:1. Compared with the above composition ratio, when the ratio of Ta is high, the light reflectance of the wavelength range of the pattern inspection light cannot be sufficiently reduced. On the other hand, when the ratio of N is higher than that of the above composition ratio, the film density is lowered, the absorption coefficient of EUV light is lowered, and sufficient absorption characteristics of EUV light are not obtained. In addition, the acid resistance will decrease.

Further, the Ta content is preferably from 50 to 90 at%, more preferably from 60 to 80 at%. The N content is preferably from 5 to 30 at%, more preferably from 10 to 25 at%.

Among them, the TaBSiN layer may also contain elements other than Ta, B, Si, and N. However, it is necessary to satisfy the absorption characteristics of the EUV light and the like as the suitability of the reticle base.

The TaBSiN layer can be formed by a known film formation method such as a sputtering method such as a magnetron sputtering method or an ion beam sputtering method. When using magnetron sputtering It can be formed by the following methods (1) to (3).

(1) Using a Ta target, a B target, and a Si target, the respective targets are simultaneously discharged in a nitrogen (N ₂ ) environment diluted with argon (Ar) to form a TaBSiN layer.

(2) Using a TaB compound target and a Si target, the respective targets are simultaneously discharged in a nitrogen atmosphere diluted with argon to form a TaBSiN layer.

(3) Using a TaBSi compound target, a target in which the three elements are integrated is discharged in a nitrogen atmosphere diluted with argon to form a TaBSiN layer. Among the above methods, in the method ((1), (2)) of simultaneously discharging two or more targets, it is possible to control the formation of the absorber layer by adjusting the input electric power of each target. composition.

Among the above, the methods (2) and (3) are preferable in that the destabilization of the discharge can be avoided or the composition of the film or the thickness of the film is uneven, and the method of (3) is particularly preferable. The TaBSi compound target is particularly preferable in that its composition is Ta = 50 to 94 at%, Si = 5 to 30 at%, and B = 1 to 20 at% to avoid the instability of the discharge or the composition of the film or the unevenness of the film thickness.

When the TaBSiN layer is formed by the above-described exemplary method, specifically, it may be carried out under the following film formation conditions.

Method of using TaB compound target and Si target (2) Sputtering gas: a mixed gas of Ar and N ₂ (N ₂ gas concentration is 3 to 80 vol%, preferably 5 to 30 vol%, and 8 to 15 vol% is more Preferably, the gas pressure is 1.0×10 ^-1 Pa to 10×10 ^-1 Pa, preferably 1.0×10 ^-1 Pa to 5×10 ^-1 Pa, and 1.0×10 ^-1 Pa to 3×10 ^-1 Pa is Better.)

Input power (for each target): 30 to 1000W, preferably 50 to 750W, preferably 80 to 500W

Film formation rate: 2.0 to 60 nm/min, preferably 3.5 to 45 nm/min, more preferably 5 to 30 nm/min

Method of using TaBSi compound target (3) Sputtering gas: a mixed gas of Ar and N ₂ (N ₂ gas concentration of 3 to 80 vol%, preferably 5 to 30 vol%, more preferably 8 to 15 vol%). 1.0 × 10 ^-1 Pa to 10 × 10 ^-1 Pa, preferably 1.0 × 10 ^-1 Pa to 5 × 10 ^-1 Pa, more preferably 1.0 × 10 ^-1 Pa to 3 × 10 ^-1 Pa.)

Input power: 30 to 1000W, preferably 50 to 750W, preferably 80 to 500W

Film formation rate: 2.0 to 60 nm/min, preferably 3.5 to 45 nm/min, more preferably 5 to 30 nm/min

A low-reflection layer having a low reflectance of the inspection light used for inspecting the mask pattern may be provided on the absorber layer. Wherein, when the low reflection layer is provided on the absorber layer, not on the surface of the absorber layer, a mark is formed on the surface of the low reflection layer. Preferably, it is preferable to form an auxiliary mark for identifying the mark around the mark formed on the surface of the low reflection layer.

When the EUV reticle is fabricated, after the absorber layer is patterned, it is checked whether the pattern is formed as designed. In the inspection of the mask pattern, an inspection machine using light of about 257 nm as inspection light is generally used. That is, it is checked by the difference in reflectance of the light of about 257 nm, The body was examined by the difference in reflectance between the surface exposed by patterning to remove the absorber layer and the surface of the absorber layer remaining without being removed by patterning. Here, the former is the surface of the reflective layer or the surface of the protective layer, generally the surface of the protective layer. Therefore, when the difference in reflectance between the surface of the protective layer and the surface of the absorber layer of the wavelength of the inspection light is small, the contrast at the time of inspection is deteriorated, and the inspection cannot be performed correctly.

The TaHf layer and the TaBSiN layer have extremely low EUV light reflectance, and have excellent characteristics in terms of the absorber layer of the EUV mask base. However, when viewed for the wavelength of the inspection light, it cannot be said that the light reflectance is necessarily very low. As a result, the difference between the reflectance of the surface of the absorber layer at which the wavelength of the light is examined and the reflectance of the surface of the protective layer becomes small, and there is a possibility that the contrast at the time of inspection cannot be sufficiently obtained. When the comparison at the time of inspection is not sufficiently obtained, the pattern defect cannot be sufficiently discriminated in the mask inspection, and the correct defect inspection cannot be performed.

By forming a low-reflection layer on the TaHf layer and the TaBSiN layer, the contrast at the inspection becomes good, in other words, the light reflectance of the wavelength of the inspection light becomes extremely low. Specifically, when the light of the wavelength region of the inspection light is irradiated onto the surface of the low reflection layer, the maximum light reflectance of the wavelength of the inspection light is preferably 15% or less, preferably 10% or less, and preferably 5% or less. For better.

If the light reflectance of the wavelength of the inspection light is 15% or less, the contrast at the time of the inspection is good. Specifically, the contrast between the reflected light of the wavelength of the inspection light in the surface of the protective layer and the reflected light of the wavelength of the inspection light in the surface of the low-reflection layer is 30% or more.

In the present specification, the comparison can be obtained by using the following formula.

Comparison (%) = ((R _{2 -} R ₁ ) / (R ₂ + R ₁ )) × 100

Here, the reflectance of the surface of the R2-based protective layer in the wavelength of light is examined, and R1 is the reflectance of the surface of the low-reflective layer. Here, the above R ₁ and R ₂ are measured in a state in which the absorber layer of the EUV mask base is patterned. The above R ₂ is a value measured by removing the absorber layer by patterning and exposing the surface of the reflective layer or the surface of the protective layer exposed to the outside, and R ₁ is a low reflection layer remaining by being removed by patterning. The value to be measured on the surface.

In the present invention, the contrast represented by the above formula is preferably 45% or more, more preferably 60% or more, and particularly preferably 80% or more.

In order to achieve the above characteristics, the low-reflection layer is made of a material having a lower refractive index than the TaHf layer and the TaBSiN layer at the wavelength of the inspection light, and the crystal state is preferably amorphous.

The low reflection layer formed on the TaHf layer is preferably a layer containing Ta, Hf and O (TaHfO layer). When the low reflection layer is a TaHfO layer, it is preferable to contain Ta, Hf and O in a specific ratio as described below.

The TaHfO layer has a total content of Ta and Hf of 30 to 80 at%, and a composition ratio of Ta to Hf (atomic ratio of Ta:Hf) of 8:2 to 4:6. When the total content of Ta and Hf is less than 30 at%, the conductivity of the TaHfO layer is lowered, and there is a possibility that charge up occurs when the electron beam is drawn. When the total content of Ta and Hf exceeds 80 at%, the light reflectance of the pattern inspection light cannot be sufficiently reduced. this Further, when Hf is lower than the above composition ratio (that is, when Hf / (Ta + Hf) < 4), the crystal state is difficult to form amorphous. When Hf is higher than the above composition ratio (that is, when Hf / (Ta + Hf) > 8), there is a possibility that the etching characteristics are deteriorated and the desired etching selectivity ratio cannot be satisfied.

The O content in the TaHfO layer is preferably from 20 to 70 at%. When the O content is less than 20 at%, there is a possibility that the light reflectance of the wavelength range of the pattern inspection light cannot be sufficiently reduced. When the O content is higher than 70 at%, the acid resistance is lowered, the low anti-insulation property is increased, and there is a possibility that charging or the like occurs during the drawing of the electron beam.

The total content of Ta and Hf in the TaHfO layer is preferably 35 to 80 at%, more preferably 35 to 75 at%. Further, the composition ratio of Ta to Hf is preferably Ta:Hf=7:3 to 4:6, more preferably 6.5:3.5 to 4.5:5.5, and particularly preferably 6:4 to 5:5. The O content is preferably from 20 to 65 at%, more preferably from 25 to 65 at%.

Among them, the TaHfO layer may contain elements other than Ta, Hf, and O as needed. At this time, the element contained in the TaHfO layer must satisfy the suitability of the EUV light absorption property or the like as a mask base.

For the example of an element that can be included in the TaHfO layer, the series is N. At this time, since the TaHfO layer contains N, the surface smoothness is improved.

When the TaHfO layer contains N (that is, when the TaHfON layer is used), it is preferable that the total content of Ta and Hf is 30 to 80 at%, and the composition ratio of Ta to Hf is Ta: Hf = 8:2 to 4:6, N. The total content of O and O is 20 to 70 at%, and the composition ratio of N to O (atomic ratio of N:O) is 9:1 to 1:9. When the total content of Ta and Hf is less than 30 at%, there is conduction. The possibility is reduced, and the possibility of charging occurs when the electronic line is drawn. When the total content of Ta and Hf exceeds 80 at%, the light reflectance of the pattern inspection light cannot be sufficiently reduced. When Hf is less than the above composition ratio, there is a possibility that the crystalline state cannot be formed into an amorphous state. When Hf is higher than the above composition ratio, there is a possibility that the etching characteristics are deteriorated and the desired etching selectivity ratio cannot be satisfied. Further, when the N and O contents are less than 20 at%, there is a possibility that the light reflectance in the wavelength range of the pattern inspection light cannot be sufficiently reduced. When the N and O contents are higher than 70 at%, there is a possibility that the acid resistance is lowered, the insulation property is increased, and charging or the like occurs during the drawing of the electron beam.

In the TaHfON layer, the total content of Ta and Hf is preferably 35 to 80 at%, more preferably 35 to 75 at%. Further, the composition ratio (atomic ratio) of Ta to Hf is preferably Ta:Hf=7:3 to 4:6, more preferably 6.5:3.5 to 4.5:5.5, and 6:4 to 5:5. Very good. The total content of N and O is preferably from 20 to 65 at%, more preferably from 25 to 65 at%.

Since the TaHfON layer has the above configuration, its crystalline state is amorphous, and the surface smoothness is good. Specifically, the surface roughness (rms) is 0.5 nm or less.

As described above, in order to prevent the dimensional accuracy of the pattern from being deteriorated due to the influence of the edge roughness, the surface of the absorber layer is required to be smooth. The TaHfON layer formed as a low reflection layer on the absorber layer is required to have a smooth surface.

If the surface roughness (rms) of the surface of the TaHfON layer is 0.5 nm Since the surface is very smooth, there is no possibility that the dimensional accuracy of the pattern is deteriorated due to the influence of the edge roughness. The surface roughness (rms) of the surface of the TaHfON layer is preferably 0.4 nm or less, more preferably 0.3 nm or less.

Among them, the crystalline state of the TaHfON layer is amorphous, that is, an amorphous structure or a microcrystalline structure, which can be confirmed by X-ray diffraction (XRD). When the crystal state of the TaHfON layer is an amorphous structure or a microcrystalline structure, a sharp peak is not observed in the diffraction peak obtained by XRD measurement.

The TaHfO layer and the TaHfON layer can be formed by performing a sputtering method using a TaHf compound target, for example, a magnetron sputtering method or an ion beam sputtering method.

Among them, in the case of the TaHfO layer, it is formed by discharging a TaHf compound target in an oxygen (O ₂ ) environment diluted with, for example, argon. Alternatively, the TaHf compound target may be discharged in an inert gas atmosphere to form a film containing Ta and Hf, for example, exposed to an oxygen plasma, or irradiated with an ion beam using oxygen, thereby oxidizing the formed film to form a film. It is the TaHfO layer.

On the other hand, if it is a TaHfON layer, by oxygen (O ₂ ) diluted with argon. The TaHf compound target is formed by discharging in a nitrogen (N ₂ ) mixed gas atmosphere. Alternatively, the TaHf compound target may be discharged in a nitrogen (N ₂ ) environment diluted with argon to form a film containing Ta, Hf, and N, for example, exposed to an oxygen plasma, or irradiated with an ion beam using oxygen, Thereby, the formed film is oxidized to form a TaHfON layer.

In the TaHf compound target, the composition is Ta = 30 to 70 at%, Hf It is preferable that the TaHfO layer and the TaHfON layer having a desired composition can be obtained at a ratio of 70 to 30 at%, and the composition of the film or the thickness of the film can be avoided. The TaHf compound target may also contain 0.1 to 5.0 at% of Zr.

In order to form the TaHfO layer and the TaHfON layer by the above method, specifically, it may be carried out by the following film formation conditions.

When a TaHfO layer is formed, a sputtering gas: a mixed gas of Ar and O ₂ (O ₂ gas concentration of 3 to 80 vol%, preferably 5 to 60 vol%, preferably 10 to 40 vol%; gas pressure 1.0 × 10 ^-1) Pa to 50 × 10 ^-1 Pa, preferably 1.0 × 10 ^-1 Pa to 40 × 10 ^-1 Pa, preferably 1.0 × 10 ^-1 Pa to 30 × 10 ^-1 Pa)

Input power: 30 to 1000W, preferably 50 to 750W, preferably 80 to 500W

Film formation rate: 2.0 to 60 nm/min, preferably 3.5 to 45 nm/min, and preferably 5 to 30 nm/min.

Sputter gas when forming the TaHfON layer: a mixed gas of Ar and O ₂ and N ₂ (O ₂ gas concentration 5 to 40 vol%, N ₂ gas concentration 5 to 40 vol%, O ₂ gas concentration 6 to 35 vol%, N ₂ The gas concentration is preferably 6 to 35 vol%, preferably 10 to 30 vol% of the O ₂ gas concentration, and 10 to 30 vol% of the N ₂ gas concentration; the gas pressure is 1.0 × 10 ^-1 Pa to 50 × 10 ^-1 Pa to 1.0 ×. 10 ^-1 Pa to 40 × 10 ^-1 Pa is preferred, preferably 1.0 × 10 ^-1 Pa to 30 × 10 ^-1 Pa)

Input power: 30 to 1000W, preferably 50 to 750W, with 80 Better than 500W

Film formation rate: 2.0 to 60 nm/min, preferably 3.5 to 45 nm/min, more preferably 5 to 30 nm/min

The low reflection layer formed on the TaBSiN layer is preferably a layer (TaBSiO layer) containing Ta, B, Si, and O. When the low reflection layer is a TaBSiO layer, it is preferable to contain Ta, B, Si, and O in a specific ratio described below.

The B content of the TaBSiO layer is 1 at% or more and less than 5 at%. As described above, when a film containing Ta and B (TaB film, TaBN film, TaBO film, TaBNO film) is used, in order to form a crystalline state of the film to be amorphous, it is necessary to form a B content of the film. It is 5at% or more. In the present invention, since the TaBSiO layer contains Ta, B in a specific ratio , Si and O, even if the B content is less than 5 at%, the crystalline state is also amorphous.

When the B content is less than 1 at%, in order to form the crystalline state to be amorphous, it is necessary to increase the amount of addition of Si. Specifically, it is necessary to form the Si content to more than 25 at%, and depending on the Si content or the film thickness of the TaBSiN layer, the absorber layer and the low reflection required for forming the EUV light reflectance to 0.5% or less. The film thickness of the layer will become larger, so it is less ideal. . When the B content is 5 at% or more, the same problem as that described for the TaBSiN layer occurs when the film formation rate is slow.

The B content is preferably from 1 to 4.5 at%, more preferably from 1.5 to 4 at%.

The Si content is 1 to 25 at%. When the Si content is less than 1 at%, the crystalline state is not formed into an amorphous state. The absorption coefficient of Si-based EUV light is higher a low material, so when the Si content exceeds 25 at%, it depends on the Si content or the film thickness of the TaBSiN layer, but the EUV light reflectance is required to be 0.5% or less of the desired absorber layer and the low reflection layer. The total thickness of the film becomes large, which is less desirable.

The Si content is preferably from 1 to 20 at%, more preferably from 2 to 10 at%.

In the TaBSiO layer, Ta and O are the residues other than B and Si. The composition ratio of Ta to O in the TaBsiO layer (atomic ratio of Ta:O) is from 7:2 to 1:2. Compared with the above composition ratio, when the ratio of Ta is high, the light reflectance of the wavelength range of the pattern inspection light cannot be sufficiently reduced. On the other hand, when the ratio of O is higher than that of the above composition ratio, the insulation property is high, charging occurs during electron beam drawing, film density is lowered, insulation is increased, and charging occurs during electron beam drawing. Therefore, it is less than ideal. Among them, the film thickness of the TaBSiO layer is thinner than that of the TaBSiN layer, and charging is less likely to occur. Therefore, the upper limit of the O content ratio is more moderate than that of the TaBSiN layer.

The composition ratio of Ta to O in the TaBSiO layer (atomic ratio of Ta:O) is preferably from 7:2 to 1:1, more preferably from 2:1 to 1:1.

The TaBSiO layer may contain N in addition to Ta, B, Si, and O. That is, it may also be a TaBSiON layer.

The TaBSiON layer preferably contains Ta, B, Si, O and N in a specific ratio as described below.

Among them, since the TaBSiON layer contains N, the surface smoothness is improved.

The B content of the TaBSiON layer is 1 at% or more and less than 5 at%. When the B content is less than 1 at%, in order to form the crystalline state to be amorphous, it is necessary to increase the amount of addition of Si. Specifically, the Si content is required to be more than 25 at%, and depending on the Si content or the film thickness of the absorber layer, the absorber layer and the low reflection required to form the EUV light reflectance to 0.5% or less are required. The total thickness of the layers is increased, which is less desirable. When the B content is 5 at% or more, the same problem as described for the TaBSiN layer occurs when the film formation rate is slow.

The B content is preferably from 1 to 4.5 at%, more preferably from 2 to 4.0 at%.

The TaBSiON layer has a Si content of 1 to 25 at%. When the Si content is less than 1 at%, the crystalline state is not formed into an amorphous state. Since the Si-based EUV light has a low absorption coefficient, when the Si content exceeds 25 at%, the Si content or the film thickness of the TaBSiN layer varies depending on the EUV light reflectance of 0.5% or less. The total thickness of the desired absorber layer and the low-reflection layer is increased, which is less desirable.

The Si content is preferably from 1 to 20 at%, more preferably from 2 to 10 at%.

In the TaBSiON layer, the residues other than B and Si are Ta, O, and N. The composition ratio of Ta to O and N in the TaBSiON layer (Ta: (atomic ratio of O + N) is 7:2 to 1:2. Compared with the above composition ratio, when the ratio of Ta is high, the pattern cannot be sufficiently reduced. Checking the light reflectance in the wavelength range of light. On the other hand, when the ratio of O and N is higher than that of the above composition ratio, acid resistance is lowered, insulation is increased, and electrons are generated. Problems such as charging up occur when the line is drawn.

The composition ratio of Ta to O and N in the TaBSiON layer (Ta: (atomic ratio of O + N) is preferably from 7:2 to 1:1, more preferably from 2:1 to 1:1.

Since the TaBSiO layer and the TaBSiON layer have the above-described configuration, the crystal state thereof is amorphous, and the surface smoothness is good. Specifically, the surface roughness (rms) is 0.5 nm or less.

As described above, since the dimensional accuracy of the pattern is prevented from being deteriorated due to the influence of the edge roughness, the surface of the absorber layer is required to be smooth. Therefore, the TaBSiO layer and the TaBSiON layer formed as a low reflection layer on the absorber layer are required to have a smooth surface.

When the surface roughness (rms) of the TaBSiO layer and the TaBSiON layer is 0.5 nm or less, since the surface is very smooth, there is no possibility that the dimensional accuracy of the pattern is deteriorated due to the influence of the edge roughness. The surface roughness (rms) is preferably 0.4 nm or less, more preferably 0.3 nm or less.

The TaBSiON layer is preferred in terms of smoothness compared to the TaBSiO layer.

The TaBSiO layer and the TaBSiON layer can be formed by a known film formation method such as a sputtering method such as a magnetron sputtering method or an ion beam sputtering method. When the magnetron sputtering method is used, the following (1) can be used. The method of (3) is to form a TaBSiO layer: (1) using a Ta target, a B target, and a Si target, and simultaneously causing the respective targets in an oxygen (O ₂ ) environment diluted with argon (Ar) Discharge, thereby forming a TaBSiO layer.

(2) A TaB compound target and a Si target are used, and the targets are simultaneously discharged in an oxygen atmosphere diluted with argon, thereby forming a TaBSiO layer.

(3) Using a TaBSi compound target, the target in which the three elements are integrated is discharged in an oxygen atmosphere diluted with argon, thereby forming a TaBSiO layer.

In the above method, in the method ((1), (2)) of simultaneously discharging two or more targets, the composition of the formed TaBSiO layer can be controlled by adjusting the input power of each target.

The methods (2) and (3) above are preferable in that the discharge is unstable or the composition of the film or the film thickness is uneven, and the method (3) is particularly preferable. Among the TaBSi compound targets, the composition is Ta = 50 to 94 at%, Si = 5 to 30 at%, and B = 1 to 20 at%, which is particularly preferable since it can avoid discharge destabilization or film composition or film thickness unevenness.

In the formation of the TaBSiON layer, instead of the oxygen environment diluted with argon It can also be diluted with oxygen in argon. In the nitrogen mixed gas atmosphere, the same procedure as described above is carried out.

When the TaBSiO layer is formed by the above method, specifically, it may be carried out under the following film forming conditions.

Method of using TaB compound target and Si target (2) Sputtering gas: a mixed gas of Ar and O ₂ (O ₂ gas concentration is 3 to 80 vol%, preferably 5 to 30 vol%, and 8 to 15 vol% is more Preferably, the gas pressure is 1.0×10 ^-1 Pa to 10×10 ^-1 Pa, preferably 1.0×10 ^-1 Pa to 5×10 ^-1 Pa, and 1.0×10 ^-1 Pa to 3×10 ^-1 Pa is Better.)

Input power (for each target): 30 to 1000W, preferably 50 to 750W, preferably 80 to 500W

Film formation rate: 2.0 to 60 nm/min, preferably 3.5 to 45 nm/min, more preferably 5 to 30 nm/min

Method of using a TaBSi compound target (3) Sputtering gas: a mixed gas of Ar and O ₂ (O ₂ gas concentration is 3 to 80 vol%, preferably 5 to 30 vol%, more preferably 8 to 15 vol%. Gas pressure 1.0 × 10 ^-1 Pa to 10 × 10 ^-1 Pa, preferably 1.0 × 10 ^-1 Pa to 5 × 10 ^-1 Pa, more preferably 1.0 × 10 ^-1 Pa to 3 × 10 ^-1 Pa.)

Input power: 30 to 1000W, preferably 50 to 750W, preferably 80 to 500W

Film formation rate: 2.0 to 50 nm/min, preferably 2.5 to 35 nm/min, more preferably 5 to 25 nm/min

When the TaBSiON layer is formed by the above method, specifically, it may be carried out under the following film forming conditions.

Method of using TaB compound target and Si target (2) Sputtering gas: mixed gas of Ar and O ₂ and N ₂ (O ₂ gas concentration 5 to 30 vol%, N ₂ gas concentration 5 to 30 vol%, O ₂ The gas concentration is 6 to 25 vol%, and the N ₂ gas concentration is preferably 6 to 25 vol%, more preferably 10 to 20 vol% of the O ₂ gas concentration, and 15 to 25 vol% of the N ₂ gas concentration. The gas pressure is 1.0 × 10 ^-2 Pa to 10 ×10 ^-2 Pa is preferably 1.0 × 10 ^-2 Pa to 5 × 10 ^-2 Pa, more preferably 1.0 × 10 ^-2 Pa to 3 × 10 ^-2 Pa.)

Input power (for each target): 30 to 1000W, preferably 50 to 750W, preferably 80 to 500W

Film formation rate: 2.0 to 50 nm/min, preferably 2.5 to 35 nm/min, more preferably 5 to 25 nm/min

Method of using TaBSi compound target (3) Sputtering gas: mixed gas of Ar and O ₂ and N ₂ (O ₂ gas concentration 5 to 30 vol%, N ₂ gas concentration 5 to 30 vol%, O ₂ gas concentration 6 to 25 vol%, N ₂ gas concentration is preferably 6 to 25 vol%, more preferably O ₂ gas concentration 10 to 20 vol%, and N ₂ gas concentration 15 to 25 vol%. Gas pressure 1.0 × 10 ^-2 Pa to 10 × 10 ^-2 Pa is preferably 1.0 × 10 ^-2 Pa to 5 × 10 ^-2 Pa, more preferably 1.0 × 10 ^-2 Pa to 3 × 10 ^-2 Pa.)

Input power: 30 to 1000W, preferably 50 to 750W, preferably 80 to 500W

Film formation rate: 2.0 to 50 nm/min, preferably 2.5 to 35 nm/min, more preferably 5 to 25 nm/min

The thickness of the absorber layer is preferably from 50 to 100 nm. Further, when a low reflection layer is formed on the absorber layer, the total film thickness of the absorber layer and the low reflection layer is preferably in the above range. However, when the film thickness of the low-reflection layer is larger than the film thickness of the absorber layer, the EUV light absorption characteristics of the absorber layer are lowered. Therefore, the film thickness of the low-reflection layer is preferably smaller than the film thickness of the absorber layer. Therefore, the thickness of the low reflection layer is preferably 5 to 30 nm, more preferably 10 to 20 nm.

The EUV mask substrate of the present invention may have a functional film well known in the field of EUV mask substrates in addition to the reflective layer, the protective layer, the absorber layer, and the low reflection layer. In the specific example of the functional film as described above, for example, as described in Japanese Laid-Open Patent Publication No. 2003-501823, a high dielectric coating applied to the back side of the substrate (relative to the film formation surface) is exemplified. Coating, 俾 to promote electrostatic chucking of the substrate. For this purpose, the high dielectric coating film applied to the back surface of the substrate is selected such that the electrical conductivity and thickness of the constituent material are such that the sheet resistance is 100 Ω/□ or less. The constituent material of the high dielectric coating film can be widely selected from the well-known literature. For example, a coating film having a high dielectric constant described in JP-A-2003-501823 can be applied. Specifically, a coating film made of ruthenium, TiN, molybdenum, chromium or TaSi can be applied. The thickness of the high dielectric coating film can be formed, for example, to 10 to 1000 nm. The substrate for a reticle substrate of the present invention, a substrate having a reflective layer and having a reflective layer. The substrate of the protective layer may also have a well-known functional film as shown above.

The high dielectric coating film can be formed by a known film forming method such as a sputtering method such as a magnetron sputtering method or an ion beam sputtering method, a CVD method, a vacuum vapor deposition method, or an electrolytic plating method.

<Disadvantage inspection method> In the method for inspecting the defect of the substrate for a reticle base of the present invention, when the film-forming surface of the substrate 1 is inspected by using a defect inspection machine, the mark (2a, 2b, 2c) provided on the film-forming surface of the substrate 1 is used. Relative position, more specifically, with the axis (20, 21) between the joint marks (2a, 2b, 2c) The position of the defect (3a, 3b, 3c) existing in the film formation surface of the substrate 1 is determined in terms of the relative position. Here, the disadvantage that the film formation surface of the substrate is a portion which is deformed into a concave shape or a convex shape by the film formation surface of the smooth substrate, in particular, is deformed into a concave shape having a size of 30 nm or more in terms of equivalent spherical diameter. Shaped or convex part. In a specific example of a portion that is deformed into a concave shape, a series of pits or scratches caused by polishing or the like are used. Specific examples of the portion that is deformed into a convex shape include a foreign matter or the like that is present on the film formation surface of the substrate. In the method for inspecting the defects of the substrate for a reticle substrate of the present invention, the position in the film formation surface which is a defect as described above is determined, that is, the position of the secondary element in the film formation surface is determined.

In Fig. 1, the position of the secondary element in the film formation surface of the defect 3c is determined in terms of the relative position with respect to the two axes (20, 21).

In the conventional defect inspection method, since the outer shape of the substrate is positioned as a reference, the positioning accuracy is low, and it is about 50 to 100 μm, and it is difficult to accurately determine the position where the equivalent spherical diameter is a very small defect of 30 nm. In addition, since the positioning accuracy is low, it takes a long time to determine the position of the defect. In the present invention, in terms of the relative position with respect to the two axes (20, 21), since the position of the defect (3a, 3b, 3c) is determined, the equivalent ball can be determined in a short time and with a high detection position accuracy. The diameter is a very small disadvantage of 30 nm. For example, a higher position detection reproducibility with a positional offset of +/- 150 nm or less can be detected to determine the location of the defect.

Wherein, in the inspection method of the substrate with the reflective layer of the present invention, having a reflective layer. Inspection method of substrate of protective layer, inspection of EUV mask base In the method of checking, the relative position of the two axes formed between the marks on the surface of the reflective layer, the surface of the protective layer, and the surface of the absorber layer in the same order as described above is determined to be a defect existing in the reflective layer and present in the protection. The disadvantage of the layer, the location of the disadvantages of the absorber layer. Here, the disadvantages of being present in the reflective layer, the disadvantages of being present in the protective layer, and the disadvantages existing in the absorber layer mean that the surface of the smooth reflective layer, the surface of the protective layer, and the surface of the absorber layer are respectively deformed into a concave shape or a convex shape. The portion, in particular, refers to a concave or convex portion that is deformed to have a size of 30 nm or more in terms of equivalent spherical diameter. In the specific example of the portion shown above, the series is such that deformation occurs on the surface of the reflective layer, the surface of the protective layer, and the surface of the absorber layer due to the presence of foreign matter in the reflective layer, the protective layer, and the absorber layer. a convex portion; a reflective layer, a protective layer, and an absorber layer are formed on the surface having defects, whereby the deformation of the surface of the reflective layer, the surface of the protective layer, and the surface of the absorber layer is convex or deformed into a concave shape. a portion that is formed, for example, as a result of forming a reflective layer on a film formation surface of a substrate having a defect, a portion where the deformation of the surface of the reflective layer is convex or a portion that is deformed into a concave shape; on the surface of the reflective layer having a defect or As a result of the formation of the absorber layer on the surface of the protective layer, the deformation occurring on the surface of the absorber layer is a convex portion or a portion deformed into a concave shape.

<Disadvantage Correction Method> In the method for correcting the defect of the substrate for a mask base of the present invention, the disadvantage that the position of the substrate formed in the above-described order is present on the film formation surface of the substrate is corrected. In the case of the correction method of the defect, for example, if it is a convex defect, there is a lift method in which the disadvantage is removed by wet etching using an etching liquid (lift) Off), or a method of removing defects by brushing, precision grinding, or the like. In the case of a concave defect, there is a method in which a film made of a substrate material or a film having a property similar to that of a substrate material is formed on a film formation surface, and a defect is corrected by filling a concave defect. In addition, there is a method of swelling the substrate material in the vicinity of the concave defect by laser irradiation, thereby correcting the disadvantage.

Wherein, the method for correcting the defect of the substrate with the reflective layer of the present invention has a reflective layer. In the case of the defect correction method of the substrate of the protective layer, the disadvantages of the reflective layer existing in the above-described order and the disadvantages existing in the protective layer are corrected.

<Method of Manufacturing EUV Photomask> In the method of manufacturing an EUV mask of the present invention, the position where the EUV mask base is patterned is finely adjusted according to the position of the defect determined in the above-described order. Specifically, fine-tuning the pattern on the EUV mask base in such a manner that the disadvantage does not exist at the position affecting the formed pattern, or in a manner that minimizes the adverse effect of the defect on the patterning accuracy Location. When there is a defect in the reflective layer or the protective layer which is exposed to the outside by patterning to remove the absorber layer, the formed pattern is adversely affected.

The disadvantages shown above are that the position of the patterning is fine-tuned in such a manner that the area of the absorber layer remains after patterning, and the formed pattern can be prevented from being adversely affected. Further, for example, when there is a disadvantage in that the reflective layer or the protective layer exposed to the outside is removed by patterning, the size of the semiconductor element circuit for reducing the resist on the wafer is reduced by the target. The value is offset and the patterning accuracy is impaired, so it is less desirable. Here, the influence of the defect on the patterning accuracy depends on the horizontal distance of the absorber layer remaining after patterning and the disadvantage of being exposed to the outside, and therefore the patterning is performed in such a manner that the influence thereof is minimized. The position is fine-tuned, whereby the adverse effects on the patterning accuracy can be minimized.

(industrial use possibility)

With the high integration of the semiconductor elements, it is necessary to prevent the occurrence of defects in the position where the pattern is affected when manufacturing the EUV mask, or the effect of the defects on the pattern accuracy is suppressed to a minimum.

The entire disclosure of Japanese Patent Application No. 2007-108060, the entire disclosure of which is hereby incorporated by reference in its entirety in its entirety in its entirety in

1‧‧‧Substrate

11‧‧‧108×132mm□

12‧‧‧149×149mm□

2a to 2c‧‧‧ mark

20, 21‧‧‧Axis between the links

3a to 3c‧‧‧ disadvantages

Fig. 1 is a plan view showing an example of a substrate for a mask base of the present invention.

Figure 2 is a schematic diagram for explaining the volume V used in calculating the equivalent spherical diameter.

Fig. 3 is a graph showing the relationship between the SEVD of the mark formed on the substrate and the maximum displacement amount (maximum offset amount) of the detected position of the mark obtained by the defect inspection machine.

Fig. 4 is a diagram showing an example of the arrangement of the mark and the auxiliary mark.

Claims (24)

A substrate for a reflective reticle base for ultra-violet (EUV) lithography, characterized in that at least 3 of the following (1) and (2) are formed outside the exposed region when the film formation surface of the substrate is patterned; The marks are: (1) the mark size is 30 to 100 nm in terms of equivalent spherical diameter; (2) on the film formation surface, the three marks are not in the same imaginary line. The substrate for a reflective reticle base for ultra-violet (EUV) lithography according to the first aspect of the invention, wherein the distance between the marks is 150 nm or more. The substrate for a reflective reticle base for ultra-violet (EUV) lithography according to the first or second aspect of the invention, wherein the film formation surface of the substrate is formed outside the exposed region at the time of patterning. To identify the auxiliary mark of the aforementioned mark. A substrate having a reflective layer for ultra-violet (EUV) lithography, which is formed on a substrate to form a reflective layer for ultra-ultraviolet (EUV) lithography for reflecting a reflective layer of ultra-ultraviolet light, characterized by the aforementioned reflection The surface of the layer is formed with at least three marks satisfying the following (1), (2) outside the exposed region at the time of patterning: (1) the mark size is 30 to 100 nm in terms of equivalent spherical diameter; (2) on the surface of the reflective layer On top, the three markers are not in the same imaginary line. A substrate having a reflective layer for ultra-violet (EUV) lithography, which sequentially forms a reflective layer for reflecting ultra-ultraviolet light on a substrate; and an ultra-ultraviolet (EUV) micro-protection layer for protecting the reflective layer a substrate for a reflective layer, characterized in that when the surface of the protective layer is patterned At least three marks satisfying the following (1) and (2) are formed outside the exposed region: (1) the mark size is 30 to 100 nm in terms of equivalent spherical diameter; (2) on the surface of the protective layer, the three marks are not in the same Imaginary line. A substrate having a super-ultraviolet (EUV) lithographic reflection layer as described in claim 4 or 5, wherein the distance between the marks is 150 nm or more. A substrate having a super-ultraviolet (EUV) lithographic reflection layer as described in claim 4, wherein an auxiliary mark for identifying the mark is formed outside the exposed region of the surface of the reflective layer at the time of patterning. A substrate having a super-ultraviolet (EUV) lithographic reflection layer as described in claim 5, wherein an auxiliary mark for identifying the mark is formed outside the exposed region of the surface of the protective layer at the time of patterning. A super-ultraviolet (EUV) lithography reflective reticle substrate, which sequentially forms a reflective layer for reflecting ultra-ultraviolet light on a substrate; and an ultra-violet (EUV) lithography for absorbing an ultra-ultraviolet absorber layer A reflective reticle substrate characterized in that at least three marks satisfying the following (1) and (2) are formed outside the exposed region of the surface of the absorber layer at the time of patterning: (1) the mark size is equivalent to the spherical diameter Calculated as 30 to 100 nm; (2) On the surface of the absorber layer, the three marks are not in the same imaginary line. A super-ultraviolet (EUV) lithography reflective reticle substrate, wherein a reflective layer for reflecting ultra-ultraviolet light is sequentially formed on a substrate; an absorber layer for absorbing ultra-ultraviolet light; and a mask pattern for inspection A reflective reticle substrate for ultra-ultraviolet (EUV) lithography for inspecting a low-reflection layer having low light reflection, which is characterized in that the surface of the low-reflection layer is formed outside the exposed region at the time of patterning to satisfy the following (1) And (2) at least three marks: (1) the mark size is 30 to 100 nm in terms of equivalent spherical diameter; (2) on the surface of the low reflection layer, the three marks are not in the same imaginary line. The reflective reticle substrate for ultra-ultraviolet (EUV) lithography according to claim 9 or 10, wherein a protective layer for protecting the absorber layer is formed between the reflective layer and the absorber layer. . The ultra-ultraviolet (EUV) lithography reflective reticle substrate according to claim 9 or 10, wherein the distance between the marks is 150 nm or more. The super-ultraviolet (EUV) lithography reflective reticle substrate according to claim 9, wherein an auxiliary mark for identifying the mark is formed outside the exposed region of the surface of the absorber layer at the time of patterning. The reflective reticle substrate for ultra-ultraviolet (EUV) lithography according to claim 10, wherein the surface of the low-reflection layer is additionally formed outside the exposed region during patterning to identify the target Auxiliary mark. A method for inspecting defects of a substrate for a reflective reticle for ultra-violet (EUV) lithography according to any one of claims 1 to 3, wherein the method of forming the film-forming surface is The step of patterning the mark outside the exposed area to determine the location of the defect. A method for correcting a defect of a substrate for a reflective reticle for ultra-violet (EUV) lithography according to any one of claims 1 to 3, wherein the method of forming the film-forming surface is The step of patterning the mark outside the exposed area to determine the position of the defect; and the step of correcting the disadvantage of the position determined in the step. A method for inspecting a defect of a substrate having a reflective layer for ultra-ultraviolet (EUV) lithography as described in claim 4, comprising: using a mark formed on an outer surface of the surface of the reflective layer at the time of patterning, The steps to determine the location of the defect. A method for correcting a defect of a substrate having a super-ultraviolet (EUV) lithography reflective layer as described in claim 4, comprising: using a mark formed on an outer surface of the reflective layer at the time of patterning, a step of determining the location of the defect; and a step of correcting the disadvantage of the location determined in the step. A method for inspecting a defect of a substrate having a reflective layer for ultra-ultraviolet (EUV) lithography according to claim 5, comprising: using a mark formed on an outer surface of the surface of the protective layer at the time of patterning, The steps to determine the location of the defect. An ultra-ultraviolet as described in item 5 of the patent application scope A method for correcting a defect of a substrate for a line (EUV) lithography reflective layer, comprising: a step of determining a position of a defect by using a mark formed on an outer surface of the surface of the protective layer at the time of patterning; and correcting at the step The steps in which the shortcomings of the location are determined. A method for inspecting a defect of a reflective reticle substrate for ultra-ultraviolet (EUV) lithography according to claim 9 of the invention, comprising: using a mark formed on an outer surface of the surface of the absorber layer at the time of patterning, The steps to determine the location of the defect. A method for producing a super-ultraviolet (EUV) lithography reflective reticle by using a super-ultraviolet (EUV) lithography reflective reticle substrate as described in claim 9 of the patent application, comprising: using the absorption formed in the foregoing The step of marking the surface of the body layer outside the exposed area of the pattern to determine the location of the defect; and the step of fine-tuning the position of the mask substrate for patterning based on the location of the defect determined in the step. A method for inspecting a defect of a reflective reticle substrate for ultra-ultraviolet (EUV) lithography according to claim 10, comprising: using a mark formed on an outer surface of the low-reflection layer at the time of patterning To determine the location of the fault. A method for producing a super-ultraviolet (EUV) lithography reflective reticle using an ultra-ultraviolet (EUV) lithography reflective reticle substrate as described in claim 10, which comprises: forming a reflection in the foregoing The step of marking the surface of the layer outside the exposed area of the pattern to determine the location of the defect; and the step of fine-tuning the position of the mask substrate for patterning based on the location of the defect determined in the step.